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Sewage pipes are important conduits for microplastics into the natural environment, but previous studies have paid little attention to the hydraulic characteristics of the confluence of pipe and channel, and the distribution of microplastics at the confluence. This study compared the effects of varying flow rates and particle sizes (Including 500 μm, 700 μm, and 900 μm) on microplastic migration and distribution at the confluence of pipe and channel using experimental measurements. The results obtained using flotation method indicate that flow proportions and particle sizes influence the capacity of flow to transport microplastics. Larger microplastic accumulation occurs in scour holes and separation zones characterized by lower flow velocities, while deposition decreases in acceleration zones characterized by higher flow velocities. Increasing the flow rate of the branch pipe influences the volume of each zone at the pipe-channel confluence. The elongated shape of the scour hole and the acceleration zone facilitate the downstream migration of microplastics. Moreover, the hydrophilic nature of microplastics increases after aging, and it is more likely to migrate to downstream with the water flow, making the downstream microplastics account for more proportion. These results provide valuable insights into the migration and distribution of microplastics at the confluence of pipe and channel, with practical implications for microplastic treatment strategies at these confluences. [ABSTRACT FROM AUTHOR]

The development of e-commerce applications for small-value transactions introduces significant security and privacy challenges. Micropurchases, that is, commercial operations involving micropayments, offer a practical solution that balances efficiency and security for these transactions. The increasing demand for this payment approach, especially with technologies such as the Internet of Things (IoT), highlights the need for innovative solutions. This paper presents a novel micropurchase protocol utilizing a new type of channels, termed transferable payment channels. The proposed protocol, managed through smart contracts, facilitates fair and equitable exchanges between minimal monetary units (μ -coins) and desired goods or services, enabling efficient low-value payments. Transferable payment channels enable off-chain transactions, reducing the reliance on on-chain transactions to achieve essential security features and ensure fair exchanges without a centralized intermediary or Trusted Third Party (TTP), commonly employed in traditional payment systems. The protocol outlines the processes for making purchases, handling payments, and incorporating functionalities for the transfer and reuse of payment channels by both customers and merchants. Additionally, it specifies procedures for merchants to redeem earned μ -coins and for customers to refund unused μ -coins. This comprehensive set of functions makes the protocol fully functional and highly efficient for micropurchases. By introducing transferable payment channels and minimizing reliance on centralized intermediaries, this work significantly advances the security and efficiency of micropayment systems. The proposed protocol has been implemented and analyzed for both security and performance. [ABSTRACT FROM AUTHOR]

Visible-infrared person re-identification (VI Re-ID) is designed to perform pedestrian retrieval on non-overlapping visible-infrared cameras, and it is widely employed in intelligent surveillance. For the VI Re-ID task, one of the main challenges is the huge modality discrepancy between the visible and infrared images. Therefore, mining more shared features in the cross-modality task turns into an important issue. To address this problem, this paper proposes a novel framework for feature learning and feature embedding in VI Re-ID, namely Channel Enhanced Cross-modality Relation Network (CECR-Net). More specifically, the network contains three key modules. In the first module, to shorten the distance between the original modalities, a channel selection operation is applied to the visible images, the robustness against color variations is improved by randomly generating three-channel R/G/B images. The module also exploits the low- and mid-level information of the visible and auxiliary modal images through a feature parameter-sharing strategy. Considering that the body sequences of pedestrians are not easy to change with modality, CECR-Net designs two modules based on relation network for VI Re-ID, namely the intra-relation learning and the cross-relation learning modules. These two modules help to capture the structural relationship between body parts, which is a modality-invariant information, disrupting the isolation between local features. Extensive experiments on the two public benchmarks indicate that CECR-Net is superior compared to the state-of-the-art methods. In particular, for the SYSU-MM01 dataset, the Rank1 and mAP reach 76.83% and 71.56% in the "All Search" mode, respectively. [ABSTRACT FROM AUTHOR]

A set of exact solutions is suggested for the Poisson equation in a plane region of a certain form for describing a flow of Newtonian incompressible liquid in a channel at low Reynolds numbers. The motion of an ideal liquid in a region bounded by a rotating contour, torsion of a rod, deflection of a membrane at zero displacement on the boundary of its region, and heating of a rod under certain conditions are equivalent to a mathematically formulated problem of such a flow. A possibility is demonstrated to construct approximate solutions to the said problem for certain sections of a channel, having a parabolic segment of the contour, using exact solutions to this problem. Examples are given for the construction of flow regions in a prismatic channel resting on a parabolic contour. [ABSTRACT FROM AUTHOR]

This study examines the flow dynamics and heat transfer characteristics of Maxwell fluid in a channel influenced by magnetohydrodynamics (MHD), Joule heating, thermal radiation, and boundary layer suction/blowing effects. The governing partial differential equations (PDEs) for momentum, energy, and concentration are transformed into ordinary differential equations (ODEs) using similarity transformations. The boundary value problem (BVP) is solved numerically using the bvp4c solver in MATLAB, yielding accurate solutions for velocity, temperature, and concentration profiles under various parameters. Key findings reveal that the porous parameter decreases the velocity profile but increases the temperature profile for both suction and blowing effects. Additionally, the MHD, Deborah, and Eckert numbers significantly influence the velocity and temperature profiles differently under these conditions. This study highlights the crucial role of integrating MHD, thermal, and boundary control effects to optimize performance and efficiency in engineering systems involving Maxwell fluids, with applications in polymer processing, biomedical engineering, electronics cooling, oil recovery, and chemical processing. [ABSTRACT FROM AUTHOR]

We embarked on an investigation with potential implications for studying blood flow within the cardiovascular system; keeping this application in mind, this investigation aims to provide numerical evaluations for a complex problem involving MHD flow, chemical reactivity, and energy transfer of a Maxwell fluid within a channel. The governing equations for momentum, concentration, and energy are renovated into ODEs for concentrated analysis using a similarity transformation. Dimensionless velocity, temperature, and concentration fields corresponding to steady motions of Maxwell fluid over a channel are numerically recognized using the bvp4c inbuilt software in MATLAB. We validated our results with existing work to check the gained results and got an excellent agreement. The impression of physical parameters on fluid motion is plotted and debated. The quantitative outcome of this study is that the Deborah number surges, and both velocity and temperature experience enhancement while the concentration within the fluid diminishes. This knowledge can be applied to various fields, such as material processing, biomedical engineering, and environmental sciences, to optimize processes and design systems accordingly. The outcomes and key findings of this study indicate that concentration distribution declines with the introduction of a chemical reaction and a complex Schmidt number. Additionally, the quantitative results of this learning are that the impression of the magnetic parameter is observed, resulting in reduced velocity and temperature profiles, while concentration profiles exhibit an increase across the entire domain. Furthermore, the rise in the Reynolds number corresponds to an escalation in the temperature outline. [ABSTRACT FROM AUTHOR]

The evolution of wireless communication in the presence of multipath fading and shadowing is generally strained by the worsening of propagation conditions. Thus, in order to estimate the achievable improvements of the link quality (due to channel enhancement), such a parameter as diversity gain is usually used. The diversity gain is classically defined as a limit for infinitely increasing signal-to-noise ratio (SNR) at the receiver input, theoretically attained only in asymptotics, and in practice attained at very high SNR values (e.g., 50–70 dB), which are unrealistic from the practical perspectives for wireless fading channels. In this case, a modified version of the same metric (i.e., the finite-SNR diversity gain; FSDG) was proposed. The presented research performs a comparative analysis of the FSDG for the case of a multipath channel with fading induced by second order scattering and fluctuating line-of-sight (LoS) component (i.e., fluctuating double-Rayleigh with Line-of-Sight; fdRLoS). The signal model included the hexagonal quadrature amplitude modulations (QAM) with regular and irregular constellations. For the considered problem, an exact expression for the FSDG was derived and analyzed as a function of channel parameters (responsible for fading severity and shadowing intensity) and modulation formats. It has been found that the FSDG can exceed the classical (asymptotic) diversity gain by the order of magnitude, and scenarios have been identified where this can occur (for example, the maximum is achieved under conditions of light shadowing and strong line-of-sight component). A nonmonotonic dependence of FSDG on the QAM constellation size (for any type of constellation) was found out: for low-to-moderate average SNR, for extremely weak and extremely strong LoS, the highest FSDG is achieved with smaller constellations, whereas for moderate LoS components, with larger constellations. [ABSTRACT FROM AUTHOR]

The modern communication network has advanced to such an extent that it is now possible for devices within a wireless personal area network (WPAN) to communicate among themselves directly. However, the limited shared radio resources of a WPAN lead to numerous issues, such as cross-layer interference and data collisions, which wind up affecting the quality of communication. A load based dynamic channel allocation (LB-DCA) model has been proposed to enhance the performance of device-to-device communication in WPAN. This model uses several control schemes in collaboration with interference estimation and channel load balancing mechanisms to allocate and manage the radio resources efficiently. The objective of this model is to achieve high throughput, low interference and low energy consumption. The control schemes implemented are based on distributed coordination and a cell-splitting approach. These schemes are utilized to estimate the channel usage and number of active nodes in a network. The interference estimation is done by using a new efficiency formula. Further, channel load balancing takes into account the hops and load factor values. The proposed model obtained 98.58% CSI, 95.86% MCC, 96.35% delta-P, 97.96% FMI, 99.83% BMI, 21.52% enhanced spectrum efficiency, 16.38% enhanced scalability, 18.79% enhanced signal quality, 18.64% enhanced power control and 18.89% enhanced energy efficiency. [ABSTRACT FROM AUTHOR]

With the advent of fifth Generation of cellular communication with its key features that superior over all the precedent generations. However, there are some challenges need to be taken into consideration. The main crucial part of communication system is the receiver and as it is known there are two main types of receivers which can be used to demodulate the signals and recover the transmitted data. In this paper, we used those two types of algorithm receivers which are the Non-Coherent and Coherent receivers. They are firstly demonstrated in details in accordance with receiver specification design and then moved to the practical side of implementation. In which novelty of our work is highlighted, by carrying out those different algorithms on the ADSP 21364 SHARC board where initially sampling the received DPSK signal, design the Bandpass and lowpass digital filtering respectively and all to be compiled by Analog Devices VisualDSP + + software that is programmed by C language prior to download to the ADSP Board chip. The same algorithm is followed in the frame synchronization for both of them by detecting the message through distinguishing the preamble of the message " + + + + " data which is before the 72 bytes (real message).Then that actual message will be stored and dumped to the memory and displayed to ensure from the received message whether it is corrupted with errors or not. However, it is clearly noticed that the Coherent receiver is more efficient than the Non-coherent, but it still a bit expensive because used double look-up tables for cosine and sine in IQ converter. Finally, coherent receiver with Costas loop algorithm was implemented as well to improve the previous differential detection scheme. [ABSTRACT FROM AUTHOR]

The process by which debris flows shift from an active channel and branch out into new transport or depositional areas is termed "avulsion." They pose serious risks for structures and populations on debris-flow fans, yet avulsion mechanisms are relatively unknown and unaccounted for in hazard assessments, as compared to avulsions of rivers and streams, which are better understood. This study analyzes six debris-flow fans in the White Mountains of California and Nevada to identify relationships between avulsion locations and channel characteristics, constrain the controlling factors on avulsion, assess the probability that avulsion will occur at specified locations, and develop a method to predict avulsion locations. A database of avulsion locations and their channel characteristics was compiled in the field. These were compared to the characteristics of other positions on the fan surface that show evidence of debris flows that did not avulse through stepwise, binary logistic regression. Results indicate that two-thirds of avulsion likelihood can be attributed to the percentage of boulders at the site, slope angle, channel width, and the ratio between flow thickness and average slope at the avulsion location. The accuracy of this model can be improved when it accounts for the presence of a coarse channel plug, which increases the likelihood of avulsion. Application of the model is demonstrated by runout simulations with forced avulsions from modeled channel plugs. [ABSTRACT FROM AUTHOR]

Pellets have voids in their structure, which form a pore space. Pellet pores can be represented by closed volumes or channels, capillaries. The volume of capillaries can be estimated by impregnating pellets with water. The purpose of this work is to assess the possibility of studying the pore space of burnt pellets using the capillary-porous solids model. For this purpose, samples of laboratory and industrial pellets were presented. According to the data obtained, samples with a high moisture capacity value have a higher recoverability. This method of evaluating the pores of burnt pellets provides information about open porosity, which can be used to predict their recoverability. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the Leray problem for steady Navier–Stokes system with full slip boundary conditions in a two-dimensional channel with straight outlets. The existence of solutions with arbitrary flux in a general channel supplemented with slip boundary conditions, which tend to the associated shear flows at far fields, is established. Furthermore, if the flux is suitably small, the solution is proved to be unique. One of the crucial ingredients is to construct an appropriate flux carrier and to show a Hardy type inequality for flows with full slip boundary conditions. [ABSTRACT FROM AUTHOR]

Quantum coherence and quantum correlations are important components of quantum information theory, which play important roles in quantum information processing. In this paper, we quantify correlations from coherence. The correlations relative to channels via metric-adjusted skew information are put forward. The corresponding results are suitable for special channels, such as positive operator-valued measurements (POVMs), projection measurements and von Neumann measurements. In addition, we discuss the dynamics of quantum correlations in the Bell-diagonal state relative to some classical channels via metric-adjusted skew information. The typical two are the Werner state and the isotropic state. We find that some separable states in entanglement resources theory possess correlations. It also shows quantum channels will disturb quantum states and have a great influence on the correlations. The correlations relative to different channels via different versions of metric-adjusted skew information have their advantages. This has inspired one to study the problem of the existence and action of various quantum correlations in quantum theory to be easily applied to experiments. [ABSTRACT FROM AUTHOR]

A model of the multichannel queuing system is considered. Each channel contains some service lines. There are several input flows. Each customer requires several lines to be serviced. If the channel does not have a sufficient number of service lines, it is possible to reorient this customer to another channel. The service line has a distribution function of a general form depending both on the flow and on the number of lines required by the customer. A fast simulation method aimed to evaluate the blocking probability of customers of a certain flow with a given number of service lines is proposed. The method is compared with the Monte Carlo method using numerical example, and the gain in simulation time is illustrated in particular. [ABSTRACT FROM AUTHOR]

The problem of a fully developed turbulent flow and developed heat transfer was solved numerically at a Reynolds number ranging from 5 × 104 to 2 × 105 for a spatially periodic model of a one-sided ribbed channel as a prototype of the flow path of an internal convective cooling system for a gas turbine blade. The flow and heat transfer were investigated at the Prandtl number of 0.7. The channel has a rectangular cross-section with an aspect ratio of 1.5. Square ribs with a 10% rib-to-channel height ratio are installed on one of the wide channel walls at an angle of 45° to the longitudinal axis of the channel. To quantify the effect of ribs on the flow and heat transfer, the integral parameters, such as hydraulic resistance factor and Nusselt number determined from the grid-converged solutions, are compared with the integral parameters for a fully developed flow and heat transfer in a smooth channel predicted by the same numerical method. The results of numerical simulation for the ribbed channel are also compared with published experimental data obtained under partly similar conditions. The predicted hydraulic resistance factor agrees well with the experiment. The predicted heat transfer agrees with the experiment within 11%, but the trends in heat transfer with increasing Reynolds number obtained using numerical and physical simulation are different. This difference may be caused by the fact that fully developed heat transfer could not be attained in the short experimental channel. Analytical power-law dependences on the Reynolds number are obtained for the hydraulic resistance factor and the Nusselt number pertaining to all channel walls and only to the ribbed wall. It is pointed out that the hydraulic resistance factor depends weakly on the Reynolds number, which is typical for local resistances, and the dependences for Nusselt numbers corrected for the specifics of the problem are close to the dependences for near-wall layers and flows in smooth channels. [ABSTRACT FROM AUTHOR]

This article presents methods for determining the relationship between the flow and hydraulic parameters of rivers, channels, and channel processes based on correlation analysis. [ABSTRACT FROM AUTHOR]

The generation of a directed flow on the water surface in channels with sources and resonators of capillary oscillations is detected and investigated. The surface flow is caused by the movement of the liquid through the gaps between the resonators, as well as between the resonator and the channel walls, under a curved surface that is locally deformed by the sources of capillary vibrations, the transfer of energy of the locally curved surface of the liquid by capillary waves, and the transmission of wave momentum to the particles of the liquid surface in one direction. It is shown that capillary waves together with the energy transfer an excess surface, the flux density of which is equal to the flux of the surface deformation. Moving devices with a capillary-wave accelerator of the surface liquid flow are demonstrated. [ABSTRACT FROM AUTHOR]

The S-model kinetic equation is used to study the rarefied gas flow from a high-pressure tank to a low-pressure one through a flat membrane with a finite number of pores. The kinetic equation is solved numerically using a second-order accurate implicit conservative method implemented in the in-house code Nesvetay. For transitional and continuum flow regimes, numerical solutions of the compressible Navier–Stokes equations are obtained. The gas flow rate through the system of pores and the forces acting on the membrane bars are investigated as functions of the Knudsen number (Kn) at a pressure ratio of 2 : 1 in the tanks. The features of the flow field near the membrane and away from it are described. [ABSTRACT FROM AUTHOR]

A polymer with pores close to a straight line was prepared by adding a plasticizer lactic acid to cellulose propionate. We succeeded in preparing for the porous cellulose propionate (CP) by a low-cost and eco-friendly manufacturing process with water treatment technology. The CP used in this study has a higher molecular weight and better mechanical strength than the cellulose acetate (CA) widely used for the membrane. In general, as the molecular weight of the polymer increases, the mechanical strength can be stronger. Thus, porous CP can be manufactured as a single film without additional polymer support. The additive LA can penetrate into the CP chains and plasticize the membrane to form pores. The manufactured membrane was installed in a water treatment machine and hydraulic pressure was applied from 2 to 7 bar. The surface and the cross-section of the membrane were verified using SEM, and the membrane, to which hydraulic pressure was applied with a plasticizer, showed a surface in which pores were generated. Then, FT-IR was investigated to confirm how the interaction between the functional groups between CP and LA changed. [ABSTRACT FROM AUTHOR]

As emerging technologies, numerous studies were carried out based on multiple input multiple output (MIMO) visible light communication (VLC) system that includes both experimental and theoretical demonstrations. MIMO-VLC system significantly suffers from performance deficiency. Recently, Orthogonal Frequency division multiplexing is utilized for maintaining transmission rate and spectral efficiency. LED selection process plays a vital role in enhancing efficiency of generalized LED index modulation system with the adoption of MAP detection component that is greatly influenced by correlation among LED. Therefore, this paper designs a novel concept named fuzzy dynamic arithmetic optimization (FDAO) algorithm for the selection of optimal channel capacity. The proposed FDAO algorithm combines the mechanism of fuzzy logic system with the dynamic arithmetic optimization algorithm to select candidates with good channel capacity. FDAO algorithm automatically extracts and removes the candidate influenced by inaccurate active decisions and optimally selects the candidate solution with good channel capacity. Finally, the comparative analysis is carried out for diverse existing approaches with respect to bit error rate (BER) and index error rate (IER). The experimental analysis reveals that the proposed approach exhibited minimum BER and IER than other techniques. [ABSTRACT FROM AUTHOR]

Wave processes on the free surface of water in a channel are considered when semicylindrical capillary waves are excited by a source and a quarter-wave resonator inside the channel. It is shown that the experimentally detected accelerating surface flows on the water surface in channels with installed sources and resonators of semicylindrical capillary waves are associated with the excitation of waveguide waves in the channel. Waveguide waves with a distributed amplitude in the form of a standing wave are formed when semicylindrical capillary waves are excited in the section of the liquid surface in a channel. For capillary waves in the channel, the liquid surface is a waveguide open at both ends; waveguide waves are formed due to the reflection of part of the semicylindrical waves from the channel walls and their interference. Waveguide waves propagate after the waves emanating from the source with acceleration and produce an accelerating surface energy flow and, together with it, a surface flow of liquid due to the transfer of momentum to particles of the liquid. In contrast to semicylindrical waves, the front line of waveguide waves within the channel are straight like in plane waves, but the amplitude and intensity of these waves are maximal along the channel axis. The waves emanating from the source in subsequent periods of oscillations are superimposed on the flow produced by the waveguide waves and, as a result, their semicylindrical front lines are extended. The principle of generating an accelerating surface fluid flow by waveguide waves in a channel with a source and a capillary wave resonator can be used to produce acoustic flows in bounded media by sources of acoustic and ultrasonic semicylindrical and hemispherical waves. Using the same principle, it is possible to obtain directed flows of microwave electromagnetic energy in waveguides with open cavity ends by a source of semicylindrical waves inside the waveguide cavity. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel signal detection algorithm to improve the performance of the multiple input multiple output (MIMO) space–time block code-orthogonal frequency-division multiplexing (STBC-OFDM) system in the underwater acoustic channel. Our special case for the underwater channel is the 114th station in the Caspian Sea. A model for an underwater MIMO-OFDM system is proposed first. Second, a signal coding method based on space–time block coding is employed. Finally, M-ZF, a modified signal detection algorithm, is then proposed for this system. Moreover, we compare M-ZF to ML, ZF, and MMSE. Another significant aspect of this paper is modeling an underwater acoustic channel using data from the Caspian Sea. In the modeling of the underwater channel, all actual conditions are considered. Ultimately, we evaluate the proposed algorithm in the underwater channel of the Caspian Sea. Simulation results demonstrate that the proposed algorithm has a lower time cost and superior bit error rate (BER) performance than others. [ABSTRACT FROM AUTHOR]

To enhance the anti-interference performance of airborne communication data link system, a transmission control method based on improved fish swarm algorithm is constructed. Firstly, the airborne data link channel model is constructed. Secondly, equalization algorithm of airborne data link is constructed, and the improved artificial fish algorithm is designed, and the algorithm procedure of transmission control of airborne communication data link system is established. Finally, simulation analysis is carried out, results show that the proposed method has higher transmission success rate, lower transmission time, and higher transmission rate, the proposed model has better performance in transmission control of airborne communication data link system. [ABSTRACT FROM AUTHOR]

The paper considers experimental data on the dynamics of superfluid helium in a U-shaped cylindrical channel. An experimental cell and a methodology for investigations, parameter measuring, and obtained data processing are described. When a heat flux is applied near the heater, vapor can appear, and the interfacial surface executes regular oscillations of macroscopic amplitude with a constant frequency. The dependences of the interfacial surface position and the corresponding parameters on time are given. The obtained experimental results are interpreted based on the earlier obtained analytical solution. [ABSTRACT FROM AUTHOR]

In Wireless Mesh Networks (WMN), at the time of network consignment and bandwidth registration, the active network consignment method did not take into consideration the intrusion, congestion load and bandwidth necessities as a whole. The significance centred bandwidth registration methods result in famishment of slightest significance congestion. Hence in this paper, we propose a Joint Channel Assignment and Bandwidth Reservation using Improved FireFly Algorithm (JCABR-IFA) in WMN. Initially the priority of each node is determined based on the channel usage, future interference and link congestion probability metrics. The bandwidth is allocated proportional to the node priority and the total number of traffic flows served by the requested node. For channel assignment and path selection, the improved FireFly Algorithm (IFA) is used. The objective function of IFA is determined in terms of link capacity, interference and flow conservation constraints. Then the channels and the path which minimize the objective function are selected by applying IFA. By simulation results we show that the proposed technique minimizes the traffic and enhances the channel efficiency. [ABSTRACT FROM AUTHOR]

The aim of this study is to report the influence of wing position (h/e) of perforated transverse baffles with square-wings (SW-PBs) on heat transfer rate and pressure drop characteristics in a channel. The channel has a cross-sectional dimension of 15 cm × 4 cm and a length of 60 cm. Two types of baffles: Solid transverse baffles and square-wing perforated transverse baffles, are comparatively tested. The baffle pitch ratio (p/e) is set to 5.0 and remains constant throughout all experiments which encompass Reynolds numbers (Re) of 6000, 9000, 12,000, 15,000, 18,000, 21,000, and 24,000. Square-wings are introduced at four different locations, h/e = 0.92 (highest wing location), 0.83, 0.75, and 0.67 (lowest wing location). The maximum heat transfer rates achieved in channels with SW-PBs at h/e = 0.92, 0.83, 0.75, and 0.67 are 148%, 157%, 166%, and 180% above that of a plain channel, while pressure losses increase by 9.51–10.69, 9.56–10.79, 9.59–10.86, and 9.64–10.99 times, respectively. Experimental results show that square-wings create multiple impinging jet flows and Nusselt number peaks appear adjacent to the rear of the perforated transverse baffles. When compared to solid transverse baffles, SW-PBs cause lower pressure losses and yield higher thermal performance. [ABSTRACT FROM AUTHOR]

Three-dimensional numerical simulation of a transverse hydrogen jet blowing into a duct with a supersonic flow of air (warmed by a fire heater) has been carried out. The study is based on experimental data obtained at the ONERA-LAERTE facility. The RANS equations for the reacting gas were solved, closed by the SST model and various kinetic mechanisms of hydrogen combustion in air. The channel wall roughness was taken into account in this model. The dependence of the flow characteristics on such physical factors as the shape of the fuel injector channel, the effective roughness height, and various methods of describing molecular diffusion has been studied. It has been established that the equivalent diameter of a grain of sand has a significant influence on the longitudinal pressure distribution in the duct. The influence of chemical kinetics on the flow structure in separation zones within the duct is demonstrated. [ABSTRACT FROM AUTHOR]

The design of an emergency labyrinth spillway, which must be constructed for the further safe use of the Shavan dam, is analyzed. Two computer hydrodynamic models were developed: (1) an initial model of the emergency spillway with a front width of 50 m and a semicircular channel in plan view; (2) an improved emergency spillway with a front width of 60 m and an almost rectilinear channel. The research was carried out by numerical hydrodynamic modeling methods using the domestic high-precision STREAM 2D CUDA software complex. [ABSTRACT FROM AUTHOR]

The patch-clamp technique represents an electrophysiology type of method. This is one of several insightful approaches with five major configurations, namely a loose patch, cell-attached (also known as on-cell), whole-cell, inside-out, and outside-out modes. The patch-clamp method is more advanced compared to classical electrophysiology since it elucidates single-channel activation in a tiny portion of the membrane in addition to action potential (AP), junction potential (JP), endplate potential (EP), electrical coupling between two adjacent cells via Gap junction hemi-channels, excitatory/inhibitory postsynaptic potentials, and resting membrane potential (RMP). In fact, a malfunction of only one channel or even one component will alter AP amplitude or duration in vitro. If parameters are inferred appropriately and recordings are performed properly, the patch-clamp trace readouts and results are robust. The main hallmarks of currents via voltage-dependent calcium (Cav), hyperpolarization-activated cyclic nucleotide gated non-selective cation (HCN), inwardly rectifying potassium (Kir), voltage-dependent potassium (Kv), and voltage-dependent sodium (Nav) channels are similar and tractable among cells even when they are derived from evolutionary distinct organs and species. However, the size of the membrane area, where the functional subunits reside, and current magnitudes vary among cells of the same type. Therefore, dividing current magnitudes by cell capacitance– current density enables the estimate of functional and active channels relative to recorded cytoplasmic membrane area. Since the patch-clamp recordings can be performed in both current- and voltage-clamp modes, the action potential or spike durations can be adequately elucidated. Sometimes, optical methods are preferred to patch-clamp electrophysiology, but the obtained signals and traces are not robust. Finally, not only an alternans of AP durations, but also that of 'action potential shape' is observed with electrophysiology. [ABSTRACT FROM AUTHOR]

Recent studies have proven the reliability of using flexible baffles in enhancing the rate of energy exchange in non-Newtonian fluids. The current study focuses on the deflection and the resulting stress in a baffle used in enhancing the heat transfer in an open trapezium filled with non-Newtonian fluid. The computational domain is a trapezoidal cavity opened to a parallel plate channel. A flexible baffle is hanged on the upper wall of the channel and its free end downwards towards the cavity center. The baffle interacts with the flow passing through the channel and also with the convective currents rising from the hot base of the cavity. The mathematical model is solved by ALE based on the finite element method. The study is performed by inspecting the roles of Reynolds number, the elasticity modulus of the baffle (governed by the Cauchy number) and the position of the baffle. The results showed that for shear thinning fluid the von Misses stress decreases with Reynolds number while for shear thickening fluid the trend is inverted. It is also found that the flexible baffle exhibits lower stress than the stiffer baffle, where at Re = 100, the von Misses stress is 518.5 and 642.7 at Ca = 10–4 and 10–5, respectively. [ABSTRACT FROM AUTHOR]

Polygonal faults (PFs) generally have a classic polygonal geometry in map view. However, under the influence of tectonic faults, diapirs, channels, and slopes, the classic polygonal geometry of PFs is not preserved, demonstrating differences (different characters) in map-view 3D seismic data covering an area of 334 km2 of the Changchang (CC) sag, are used to document the map-view and cross-sectional characteristics of PFs. These data also help investigate the irregularly polygonal geometries of PFs due to the presence of influence factors, such as transtensional faults, submarine fans, channels, diapirs/gas chimneys, and the basal slope within the lower-middle Miocene strata. Results show that various irregularly polygonal geometries of PFs can be classified into en-echelon and arcuate PFs, channel-segmenting and -bounding PFs, radial PFs, and rectangular PFs in map-view. En-echelon and arcuate PFs are induced by transtensional faults and exhibit a unique 'flower' structure in NE- and SE-trending cross-sections in the NW area of the study area. This finding is documented for the first time. Channel-segmenting PFs occur in the (northwest) low-amplitude muddy channel and are inhibited in the (southeast) high-amplitude sandy channel in the SW area. Radial PFs are radially aligned around a gas chimney/diapir containing some high-amplitude anomalies (HAAs) in the middle area. The presence of intrusive sandstones with HAAs along the periphery of the diapirs restricts the occurrence of PFs. Two high-amplitude submarine fans act as a mechanical barrier to the propagation of PFs. Meanwhile, the (moderate) slope in the NE area induces rectangular PFs. Additionally, the geneses of the PFs in the current study are comprehensively discussed. This study adds to our understanding of the differences between PFs with irregularly polygonal geometries. [ABSTRACT FROM AUTHOR]

The problems of different sections of physics and mechanics share a mathematical model that is based on the Poisson equation with a constant right-hand side and a zero (constant) value of the sought function on the contour of a two-dimensional region. A set of exact solutions to the formulated problem is presented in the "plane" region of certain form to describe the following problems: flow of a liquid in the channel at small Reynolds numbers; motion of an ideal liquid during the rotation of the contour bounding the region; torsion of a rod; deflection of the membrane at the zero displacement on the boundary of the region; heating of the rod. The possibility to construct approximate solutions for certain cross sections of the channel, etc. by using these exact solutions is noted. Examples are given. [ABSTRACT FROM AUTHOR]

Experimental data on the movement of the superfluid helium in a U-shaped cylindrical channel filled with and without a permeable porous backfill of metal monodisperse spheres are considered. The results of experiments are presented in the form of the time dependences of the position of the helium-II–vapor interface in the channel. A comparison of the amplitudes and frequencies of vibration of this interface, depending on the pressure in the channel, in the cases of free channel and where it is filled with porous backfill has been performed. It is shown that, in the channel with a monodisperse porous backfill, a stationary state of the interface is possible. [ABSTRACT FROM AUTHOR]

States and channels are fundamental and instrumental ingredients of quantum mechanics. Their interplay not only encodes information about states but also reflects uncertainties of channels. In order to quantify intrinsic uncertainties generated by channels, we exploit the action of a channel on an orthonormal basis in the space of observables from three different perspectives. The first concerns the uncertainty generated by a channel via noncommutativity between the Kraus operators of the channel and an orthonormal basis of observables, which can be interpreted as a kind of quantifier of the total uncertainty generated by a channel. The second concerns the uncertainty in terms of the Tsallis- entropy of the Jamiołkowski–Choi state associated with the channel via the channel–state duality, which can be interpreted as a quantifier of the classical uncertainty generated by a channel. The third concerns the uncertainty of a channel as the deviation from the identity channel in terms of the Hilbert–Schmidt distance, which can be interpreted as a kind of quantifier of the quantum uncertainty generated by a channel. We reveal basic properties of these quantifiers of uncertainties and establish a relation between them. We identify channels producing the minimal/maximal uncertainties for these three quantifiers. Finally, we explicitly evaluate these uncertainty quantifiers for various important channels, use them to gain insights into the channels from an information-theoretic perspective, and comparatively study the quantifiers. [ABSTRACT FROM AUTHOR]

Dynamic channel pruning has been proved to be an effective method by dynamically adjusting the inference path to reduce the computing costs. However, in most existing work, the classification performance decreases rapidly with the increase of pruning rate because their pruning strategy weakens the representation ability of the model to a certain extent. To resolve this problem, a dynamic channel pruning method based on activation gate (DCPAG) is proposed, which can better maintain the classification performance while reducing the computing costs. First, a pipeline aiming for generating pruning strategy, namely channel pruning auxiliary (CPA) is proposed, which considers both the representation ability and computing costs. Second, the pruning strategy generated by CPA is embedded into dynamic rectifying linear unit (DyReLU) to form the embedded dynamic rectifying linear unit (EB-DyReLU), which achieves dynamic channel pruning while maintaining the representation capability. Third, each input sample was self-classified according to its identification difficulty during pruning, and additional training was given to hard samples to achieve better classification performance. Finally, some experiments are carried out on CIFAR-10 and ImageNet respectively to verify the effectiveness of DCPAG in accuracy and floating point of per second (FLOPs). The results show that the proposed method achieves better performance than other similar channel-based methods at the same pruning rate. Specifically, this method not only achieves 0.5-1.5% improvement in classification accuracy, but also reduces the computational costs by 5%-20%. [ABSTRACT FROM AUTHOR]

Magnesium (Mg2+) is the most prevalent divalent intracellular cation. As co-factor in many enzymatic reactions, Mg2+ is essential for protein synthesis, energy production, and DNA stability. Disturbances in intracellular Mg2+ concentrations, therefore, unequivocally result in delayed cell growth and metabolic defects. To maintain physiological Mg2+ levels, all organisms rely on balanced Mg2+ influx and efflux via Mg2+ channels and transporters. This review compares the structure and the function of prokaryotic Mg2+ transporters and their eukaryotic counterparts. In prokaryotes, cellular Mg2+ homeostasis is orchestrated via the CorA, MgtA/B, MgtE, and CorB/C Mg2+ transporters. For CorA, MgtE, and CorB/C, the motifs that form the selectivity pore are conserved during evolution. These findings suggest that CNNM proteins, the vertebrate orthologues of CorB/C, also have Mg2+ transport capacity. Whereas CorA and CorB/C proteins share the gross quaternary structure and functional properties with their respective orthologues, the MgtE channel only shares the selectivity pore with SLC41 Na+/Mg2+ transporters. In eukaryotes, TRPM6 and TRPM7 Mg2+ channels provide an additional Mg2+ transport mechanism, consisting of a fusion of channel with a kinase. The unique features these TRP channels allow the integration of hormonal, cellular, and transcriptional regulatory pathways that determine their Mg2+ transport capacity. Our review demonstrates that understanding the structure and function of prokaryotic magnesiotropic proteins aids in our basic understanding of Mg2+ transport. [ABSTRACT FROM AUTHOR]

The solution to the problem of flexural-gravity waves in an ice-covered channel is constructed and investigated when the ice thickness varies linearly from one to another channel wall. The channel cross-section is rectangular. It is assumed that the ice-plate thickness is small as compared with the channel depth and the plate edges are frozen to the channel walls. The ice cover deflection is described within the framework of the linear theory of elastic plates, fluid flow beneath ice is assumed to be potential. The problem is solved using expansions of the plate deflection in the modes of vibration of the plate whose thickness varies linearly across the the channel width. The dispersion relations, the profiles of flexural-gravity waves across the channel, and the strain distributions in the ice cover are determined. The group and phase velocities of hydroelastic waves are found. The hydroelastic characteristics are investigated as functions of the linear coefficient of the ice thickness. The results obtained are compared with the results for the uniform ice cover. [ABSTRACT FROM AUTHOR]

Coherence is an important resource in quantum information processing; preserving coherence is a major challenge in practical scenarios. In this work, we develop the theories of the coherence-breaking channel and coherence-breaking superchannel, respectively. We define a new kind of coherence-breaking channel which is called strong coherence-breaking channel. The coherence-breaking superchannel is also introduced as a generalization of the coherence-breaking channel in the dynamical resource theory of coherence. Several equivalent characterizations of coherence-breaking superchannel are given. As a demonstration, we also study the coherence-breaking superchannel which maps a qubit channel to the other qubit channel and give the form of such superchannel. Finally, the coherence-breaking indices of superchannel are studied. [ABSTRACT FROM AUTHOR]

Like all biological and chemical reactions, ion channel kinetics are highly sensitive to changes in temperature. Therefore, it is prudent to investigate channel dynamics at physiological temperatures. However, most ion channel investigations are performed at room temperature due to practical considerations, such as recording stability and technical limitations. This problem is especially severe for the fast voltage-gated sodium channel, whose activation kinetics are faster than the time constant of the standard patch-clamp amplifier at physiological temperatures. Thus, biologically detailed simulations of the action potential generation evenly scale the kinetic models of voltage-gated channels acquired at room temperature. To quantitatively study voltage-gated sodium channels' temperature sensitivity, we recorded sodium currents from nucleated patches extracted from the rat's layer five neocortical pyramidal neurons at several temperatures from 13.5 to 30 °C. We use these recordings to model the kinetics of the voltage-gated sodium channel as a function of temperature. We show that the temperature dependence of activation differs from that of inactivation. Furthermore, the data indicate that the sustained current has a different temperature dependence than the fast current. Our kinetic and thermodynamic analysis of the current provided a numerical model spanning the entire temperature range. This model reproduced vital features of channel activation and inactivation. Furthermore, the model also reproduced action potential dependence on temperature. Thus, we provide an essential building block for the generation of biologically detailed models of cortical neurons. [ABSTRACT FROM AUTHOR]

A procedure of mathematical modeling of the characteristics of gasification of a low-melting hydrocarbon material in the flow of a heated inert gas has been proposed which is based on solving the problem of coupled heat transfer in the gas in the channel and in the region occupied by the solid hydrocarbon material. Dependences of the shape of the boundaries of the solid material on the temperature of a carrier gas and on time have been obtained. Calculation results are compared with experimental results. [ABSTRACT FROM AUTHOR]

In this paper, we propose asymptotic expansions for the velocity potential and obtain asymptotic equations of gas dynamics for irrotational isentropic flows of an ideal gas: an equation of linear theory, a nonlinear equation for supersonic flows, and a nonlinear transonic equation. We construct some exact particular solutions for the asymptotic nonlinear transonic equation, which takes into account transverse perturbations. Based on a linear asymptotic equation, we examine the dynamic stability of an elastic deformable element of a channel at a subsonic flow rate of a gas or liquid. The study of stability is carried out in a statement corresponding to small perturbations of a homogeneous flow and small deformations of an elastic element, and is based on the construction of a positive definite functional. Sufficient stability conditions are obtained. [ABSTRACT FROM AUTHOR]

In this study, the Al2O3–H2O nanofluid flow through a duct with a square cross section under a constant heat flux is simulated using a single-phase model. According to the chosen values of the Reynolds and modified Richardson numbers, this flow is laminar, and it is considered in mixed convection. The dynamic and thermal parameters of this flow are determined numerically by using the CFD-Fluent software based on the finite volume method by introducing the Boussinesq approximation. The analysis is carried out for Reynolds numbers ranging from 100 to 1000 and modified Richardson numbers equal to 0.1 and 0.5. The results obtained show that gravitational forces generate two thermo-convective cells in each cross section along the channel, and asymmetric temperature and velocity profiles are formed. The effects of the volume fraction of nanoparticles, Reynolds number, and modified Richardson number on the flow structure, Nusselt number, and pressure drop are analyzed. With the use of nanofluids, the Nusselt number increases, which ensures heat transfer enhancement. Finally, a correlation is proposed for the Nusselt number as a function of the nanoparticle volume fraction, which can be used for heat transfer predictions. [ABSTRACT FROM AUTHOR]

Influence of Equal Channel Angular Pressing on mechanical properties and fracture toughness of Al-Zn alloy were studied in present investigation. Samples are successfully processed using the ECAP technique for up to a four passes by using route A. Al-Zn alloys were heated to a solid solution treatment temperature at 550 °C for 2 h prior to ECAP, this treatment introduces the precipitates which were capable of obstructing motions of dislocation and improves the refinement of the grain during ECAP process Finally, artificial aging was performed at a temperature of 190 °C for 0-20 hours with an interval of 2 h and specimens were cooled at room temperature with natural air. Fracture toughness was found experimentally for ECAP processed samples using SE (B) specimens according to ASTM E399 standard. This study revealed the enhancement in mechanical properties such as yield strength, ultimate strength and microhardness after four passes by route A technique. The improvement in the fracture toughness properties of artificially aged ECAP samples can also be due to dislocation strengthening, grain boundary strengthening, and the creation of much finer UFG grains, according to the results. Despite the increased tensile strength after ECAP, the ductility behavior has decreased due to the precipitation of GP zones and dispersion of η, ή, T and E within the Aluminum matrix, Furthermore, scanning electron microscope (SEM) micrographs revealed that ductile fracture with large dimples occurred in the artificial aged samples after the ECAP procedure. [ABSTRACT FROM AUTHOR]

Recently calcium homeostasis modulators (CALHMs) are identified as ATP release channels play crucial role in functioning of neurons including gustatory signaling and neuronal excitability. Pathologies of Alzheimer's disease and depression have been associated with the dysfunction of CALHMs. Recently, CALHMs has been emerged as an important therapeutic research particularly in neurobiological studies. CALHM1 is most extensively studied among CALHMs and is an ATP and ion channel that is activated by membrane depolarization or removal of extracellular Ca2+. Despite the emerged role of CALHM5 shown by an recently assembled data; however, the neuronal function remains obscure until the first Cryo-EM structure of CALHM5 was recently solved by various research group which acts as a template to study the hidden functional properties of the CALHM5 protein based on structure function mechanism. It provides insight in some of the different pathophysiological roles. CALHM5 structure showed an abnormally large pore channel structure assembled as an undecamer with four transmembrane helices (TM1-TM4), an N-terminal helix (NTH), an extracellular loop region and an intracellular C-terminal domain (CTD) that consists of three α-helices CH1-3. The TM1 and NTH were always poorly defined among all CALHMs; however, these regions were well defined in CALHM5 channel structure. In this context, this review will provide insight in structure, function and mechanism to understand its significant role in pathological diseases particularly in Alzheimer's disease. Moreover, it focuses on CALHM5 structure and recent associated properties based on Cryo-EM research. [ABSTRACT FROM AUTHOR]

Direct numerical simulation is employed to study the complex vortical flow in the wake of a circular cylinder in a rectangular channel at . Formation and development of vortices behind bodies are governed by two phenomena: Karman street in the central part of the channel and a pair of spiral peripheral vortices near the channel sidewalls. Both of these phenomena introduce their own disturbances to the flow and can be essential depending on the Reynolds number and geometry of the cross section. Fourier transform yielded spectral density of kinetic energy of velocity fluctuations at fixed sample points in the flow and also revealed the patterns in formation of vortical properties of the wake, including the transition to turbulence and self- oscillations of aerodynamics coefficients of the streamlined body. [ABSTRACT FROM AUTHOR]

This article describes the operation of four-roll passes for rolling of nonsymmetrical flange channel sections. Transformation reasonability of existing two-high mill stands into universal ones is exemplified by channel section rolling at linear rolling mill. Technology and equipment are developed for fabrication of channel sections using four-roll finishing pass at medium section mill 550. Commercial verification of the proposed technical solutions confirmed their maintainability and reasonability regarding the application of rolling mills of such types fabricating nonsymmetrical flange profiles. [ABSTRACT FROM AUTHOR]

Store-operated Ca2+ entry (SOCE) represents a predominant Ca2+ influx pathway in non-excitable cells. SOCE is required for immune cell activation and is mediated by the plasma membrane (PM) channel ORAI1 and the endoplasmic reticulum (ER) Ca2+ sensor STIM1. Mutations in the Orai1 or STIM1 genes abolish SOCE leading to combined immunodeficiency (CID), muscular hypotonia, and anhidrotic ectodermal dysplasia. Here, we identify a novel autosomal recessive mutation in ORAI1 in a child with CID. The patient is homozygous for p.C126R mutation in the second transmembrane domain (TM2) of ORAI1, a region with no previous loss-of-function mutations. SOCE is suppressed in the patient's lymphocytes, which is associated with impaired T cell proliferation and cytokine production. Functional analyses demonstrate that the p.C126R mutation does not alter protein expression but disrupts ORAI1 trafficking. Orai1-C126R does not insert properly into the bilayer resulting in ER retention. Insertion of an Arg on the opposite face of TM2 (L135R) also results in defective folding and trafficking. We conclude that positive side chains within ORAI1 TM2 are not tolerated and result in misfolding, defective bilayer insertion, and channel trafficking thus abolishing SOCE and resulting in CID. [ABSTRACT FROM AUTHOR]

Physical experiment and direct numerical simulation are employed to study a transitional flow of viscous fluid past a spanwise circular cylinder mounted near the wall of a rectangular channel. The Reynolds number varies in the range of 60 to 480. Spiraling tornado-like motion of fluid directed from the sidewalls toward the center of the channel behind the cylinder is discovered. The evolution of this motion with the Reynolds number is outlined. Formation of large-scale vortical structures (analogue of Karman vortex street) and their turbulent breakdown in the cylinder wake are described. The behavior of the drag coefficient of the cylinder and the nearest wall with the Reynolds number is revealed. [ABSTRACT FROM AUTHOR]

Sound signals are acquired and digitized in the cochlea by the hair cells that further transmit the coded information to the central auditory pathways. Any defect in hair cell function may induce problems in the auditory system and hearing-based brain function. In the past 2 decades, our understanding of auditory transduction has been substantially deepened because of advances in molecular, structural, and functional studies. Results from these experiments can be perfectly embedded in the previously established profile from anatomical, histological, genetic, and biophysical research. This review aims to summarize the progress on the molecular and cellular mechanisms of the mechano-electrical transduction (MET) channel in the cochlear hair cells, which is involved in the acquisition of sound frequency and intensity—the two major parameters of an acoustic cue. We also discuss recent studies on TMC1, the molecule likely to form the MET channel pore. [ABSTRACT FROM AUTHOR]

Pannexins, large non-gap junction super family exists in vertebrates, play multiple roles in different cellular functions through their ATP release. Panx1-mediated adenosine 5′-triphosphate (ATP) release plays a vital role in physiological and pathophysiological conditions and is known major extracellular molecule in purinergic signaling. To modulate their function in vivo, a proper regulation of channel is necessary. Post-translational modifications are considered to be some regulating mechanisms for PANX1, while PANX2, PANX3 have been uncharacterized to date. Through their significant evidences, PANXs exclude from gap junction and conduits ATP release and other cellular molecules from cells by various mechanisms. PANX1 is most extensive characterized and implicated in ATP signaling and inflammatory processes. Despite the constant advances, much significance of PANX1 in physiological processes remains elusive. Recently, various research groups along with our group have reported the Cryo-EM structure of Panx1 channel and uncovered the hidden functions in structure–function mechanism as well as to provide the clear understanding in physiological and pathophysiological roles. These research groups reported the novel heptameric structure with contains 4 transmembrane helices (TM), two extracellular loops and one intracellular loop with N and C terminus located at the intracellular side. In addition, the structure contains a large pore of which an inhibitor CBX act as a plug that blocking the passage of substrate. In this context, this review will present current mechanistic understanding in structure and function together with significant physiological roles particularly ATP release in health and disease. As such, this review emphasizes on recent functional properties associated with novel heptameric channel and demystifies channel-mediated ATP release function. [ABSTRACT FROM AUTHOR]