Final Channel Research Articles

Direct Channel or Distribution Channel? The Role of Internet-Based Targeted Advertising With Vertical Differentiation in Distinct Channels

The selection of optimal channels is considered the critical marketing strategy for the firm. Effective vertical channel selection could induce distinct effects on the firm’s profit and social warfare by selecting a specific type of advertising. Otherwise, as the targeted population is quite different for the firm using mass or targeted advertising, this differentiation is becoming more significant for the population in the final marketing channel. Within the vertical differentiation model, the role of Internet-based targeted advertising on direct sales and distribution channels is studied. Compared to mass advertising, the firm using Internet-based targeted advertising in distinct channels can benefit the firm’s equilibrium profit by reducing advertising waste and enhancing the product’s price. The manufacturer might use Internet-based targeted advertising to control the total profit of the channel. Meanwhile, Internet-based targeted advertising might reduce the retailer’s and the entire channel’s profit. Otherwise, the targeting accuracy of the firm shows a bidirectional role in the firm’s equilibrium price in the direct channel. The firm’s equilibrium advertising level and profit might be reduced with the increasing targeting accuracy. The public department of the government needs to consider the potential risk of targeted advertising that might reduce the real benefits of distribution channels and harm the development of the market.

Путешествие между каналами: формирование клиентского опыта в цифровой среде

In modern marketing, researchers are focused on the omnichannel approach due to the growing number of communication channels and sources of consumer information about brands. This paper examines the complexity and multifactorial nature of the omnichannel approach in the formation of customer experience and marketing communications in the digital environment. The article discusses the concept of a “Consumer Journey Map”, which reflects the stages of making a purchase decision, after-sales interaction and the customer experience formed within this path. This approach allows you to define and analyze the touchpoints with the consumer and information messages at each stage of the consumer journey in order to create a positive brand image. The consumer’s journey is formed by the sequential passage of a number of points of contact, which may belong to the brand, its partners or be independent. This affects the degree of brand control over the information at each of these points. Particular attention is paid to the complexity of tracking the entire variety of contact points through which the customer passes on the way to making a purchase. The management of this variety of points from the standpoint of a single communication environment of brand and consumer interaction is the subject of omnichannel marketing research. Within the framework of this study, the author considers the evaluation of the effectiveness of marketing channels at the stage of preparation for purchase. These channels may be underestimated, since in terms of direct return on marketing investments, they lose to the final pre-purchase channels, but they play a key role in shaping the customer experience leading to subsequent purchases. The article presents the results of a study of online communication based on a company providing educational services. This study demonstrates the relationship between the volume of investments in paid promotion channels and the total revenue from online channels. The results of the study emphasize the importance of the omnichannel approach in modern communication, where the buyer interacts with the brand in various channels and perceives communication as a single continuous process, even when switching from one channel to another.

Effect of the building orientation on additively manufactured copper alloy: Hydraulic performance of different surface roughness channels

The additive manufacturing capabilities open new frontiers in the design of complex geometries in many different application fields, especially thermal science, in which multi-functional, efficient, compact components with internal cooling or heating channels are becoming more and more requested. Among the possible additive manufacturing technologies, the laser powder bed fusion process has recently been proven to manufacture high-conductivity metals, with good mechanical and thermal properties (i.e. pure copper and copper alloys), attracting the attention of the heat transfer community. However, depending on the material, design, and process parameters, the surface roughness of the components can remarkably change and become a critical issue in cooling applications. Currently, the surface texture characteristics and the final channel size cannot be accurately estimated a priori, and thus the initial hypothesis of the current design methods may lead to unpredictable and undesired results. This work experimentally and numerically explores the effects of the building orientation on the fluid dynamic behaviour in CuCrZr alloy channels, which is considered one of the most promising additive manufacturing materials for thermal applications. By coupling the experimental hydraulic results with surface characterization and X-ray computer tomography dimensional measurements of the channels, a novel simplified methodology to properly correlate the pressure drop to the surface texture of a single wall is proposed and numerically validated.

Theoretical Study of Electron Capture, Excitation, and Ionization Processes in H+−H(2l) Collisions

The processes of single-electron charge exchange, excitation, and ionization during proton impact on H(2l) are investigated. We employ two different theoretical methods that are suitable for different collision energy regions: the full quantum-mechanical molecular orbital close-coupling method for energies from 0.001 to 1 keV u−1 and the two-center atomic orbital close-coupling (TC-AOCC) method for energies between 0.3 and 100 keV u−1. For charge exchange and excitation processes, the total and nl-resolved cross sections to the final reaction channels of H (nl, n = 1–4) have been obtained over a broad energy region. Moreover, the ionization cross sections in the TC-AOCC calculation are also reported for both H(2s) and H(2p) initial target states. The present results are all compared with those from other sources when available. It is found that the magnitude and energy behavior of nl-resolved excitation cross sections for H+–H(2p) collisions are significantly distinct from those of the H(2s) initial state in the entire energy range considered, particularly in the low-energy region. The energy behaviors of the nl-resolved charge exchange cross sections from the H(2p) initial state are similar to those from the H(2s) initial state, but their magnitudes are larger. The present accurate cross-section data are anticipated to provide insight into the research of astrophysics and controlled fusion plasmas.

Bias-Free Access to Orbital Angular Momentum in Two-Dimensional Quantum Materials.

The demonstration of a topological band inversion constitutes the most elementary proof of a quantum spin Hall insulator (QSHI). On a fundamental level, such an inverted band gap is intrinsically related to the bulk Berry curvature, a gauge-invariant fingerprint of the wave function's quantum geometric properties in Hilbert space. Intimately tied to orbital angular momentum (OAM), the Berry curvature can be, in principle, extracted from circular dichroism in angle-resolved photoemission spectroscopy (CD-ARPES), were it not for interfering final state photoelectron emission channels that obscure the initial state OAM signature. Here, we outline a full-experimental strategy to avoid such interference artifacts and isolate the clean OAM from the CD-ARPES response. Bench-marking this strategy for the recently discovered atomic monolayer system indenene, we demonstrate its distinct QSHI character and establish CD-ARPES as a scalable bulk probe to experimentally classify the topology of two-dimensional quantum materials with time reversal symmetry.

Agronomic evaluation of iceberg lettuce cultivars in hydroponic system

Lettuce production in hydroponic cultivation has been gradually increasing, but there is great variation with respect to the available technologies, as well as to information on local performance of lettuce cultivars. The objective of this study was to evaluate 11 cultivars of iceberg lettuce in hydroponic system under cultivation under a low-density polyethylene (LDPE) cover, with 150 μm thickness, and in a screenhouse covered with ChoromatiNet®Leno red-pigmented net with 30% shading in the summer in Jataí-GO, Brazil. Two experiments were conducted in a randomized block design with three replicates, one in an environment covered with a red net and the other in a greenhouse covered with transparent plastic. The seedlings were transplanted to the final growth channel 17 days after sowing, and harvest was carried out at 33 days of final growth bench, when the following characteristics were evaluated: head formation, total chlorophyll content, soluble solids content, total fresh mass, marketable fresh mass, stem fresh mass, root fresh mass, number of leaves, stem length and stem diameter. All cultivars showed commercial standard for the fresh market in Jataí-GO.

Study of highly excited states in 16O with 3He+13C reactions at low energies

We report some preliminary experimental results on 13C(3He,α)12C reactions at low bombarding energies, in the range 1.4 – 2.2 MeV. The reconstruction of kinematic quantities in the final channel was performed by using a high-performance, low-threshold hodoscope, allowing for the particle identification even for low energy ejectiles. We succeeded in measuring detailed angular distributions, in absolute values, even for the transition leading to the emission of 12C in the Hoyle state, then resulting into 4 α particles in the final channel. The analysis of angular distributions as a function of energy suggests the occurrence of two low-spin resonant states, respectively with Jπ = 1− and 2+, at excitation energies of ≈ 24.1 and 24.5 MeV.

Alpha structure of 16O at high excitation energies by 3He+13C nuclear reactions

This work investigates high energy states in the self-conjugate 16O nucleus, through the analysis of 13C(3He,α)12C reactions in the 1.4 2.2 MeV bombarding energy range. The cross-section of the decay channel in which an α particle is emitted in coincidence with a 12C residual nucleus in the Hoyle state, leading to four α particles in the final channel, has been measured thanks to a low-threshold and high-resolution array. The occurrence of two low-spin resonant states is highlighted by the analysis of angular distributions, with Jπ = 2+ and 3−, at respective energies of ≃ 24.1 and 24.5 MeV. In this energy window, the observed branching ratios for the transition involving the emission of the Hoyle state appear to be way larger than calculations based on the barrier penetration alone, pointing out to the possible occurrence of largely clustered high-energy states in 16O.

Monte Carlo Simulation of Percolation Phenomena for Direct Current in Large Square Matrices

In this study, an in-depth analysis of the percolation phenomenon for square matrices with dimensions from L = 50 to 600 for a sample number of 5 × 104 was performed using Monte Carlo computer simulations. The percolation threshold value was defined as the number of conductive nodes remaining in the matrix before drawing the node interrupting the last percolation channel, in connection with the overall count of nodes within the matrix. The distributions of percolation threshold values were found to be normal distributions. The dependencies of the expected value (mean) of the percolation threshold and the standard deviation of the dimensions of the matrix were determined. It was established that the standard deviation decreased with the increase in matrix dimensions, ranging from 0.0262253 for a matrix with L = 50 to 0.0044160 for L = 600, which is almost six-fold lower. The mean value of the percolation threshold was practically constant and amounted to approximately 0.5927. The analysis involved not only the spatial distributions of nodes interrupting the percolation channels but also the overall patterns of node interruption in the matrix. The distributions revealed an edge phenomenon within the matrices, characterized by the maximum concentration of nodes interrupting the final percolation channel occurring at the center of the matrix. As they approached the edge of the matrix, their concentration decreased. It was established that increasing the dimensions of the matrix slowed down the rate of decrease in the number of nodes towards the edge. In doing so, the area in which values close to the maximum occurred was expanded. Based on the approximation of the experimental results, formulas were determined describing the spatial distributions of the nodes interrupting the last percolation channel and the values of the standard deviation from the matrix dimensions. The relationships obtained showed that with increasing matrix dimensions, the edge phenomenon should gradually disappear, and the percolation threshold standard deviation values caused by it will tend towards zero.

Towards self-explainable graph convolutional neural network with frequency adaptive inception

Graph convolutional neural networks (GCNs) have demonstrated powerful representing ability of irregular data, e.g., skeletal data and graph-structured data, providing the effective mechanism to fuse the neighbor nodes. However, inheriting from the deep learning, GCN also lacks interpretability, which hinders its application to scenarios that have high demand for transparency. Although, there have been many efforts on the interpretability of deep learning, they mainly concentrate on i.i.d data that is hard to be deployed to GCNs, which involve not only the node feature, but also the graph structure. There are few works that attempt to explain it with post-hoc manner, which can be biased, resulting in mis-representation of the true explanation. Therefore, in this paper, we propose a framework, namely ExpFiGCN, that reveals explainability of the GCNs from the perspective of graph structure and mathematical analysis. Specifically, ExpFiGCN can find the most intrinsically relevant node to the central node and obtain the informative and discriminative signals while performing denoising. For the graph structure, we find K-nearest nodes; for the mathematical analysis, every channel of a node and its neighborhoods contribute dynamically to the final channel signal, which can capture the inherent difference of different channels and neighbor nodes. Meanwhile, it can enhance the representation ability of nodes and ameliorate the over-smoothing problem. On the other hand, our model can dynamically adjust the importance of neighborhoods to the central vertex. We empirically validate the effectiveness of the proposed framework ExpFiGCN on various benchmark datasets. Experimental results show that our method achieves substantial improvements and outperforms the state-of-the-art performance strikingly.

An effective method to calculate the electron impact excitation cross sections of helium from ground state to a final channel in the whole energy region

The electron impact excitation (EIE) cross sections of an atom/ion in the whole energy region are needed in many research fields, such as astrophysics studies, inertial confinement fusion researches and so on. In the present work, an effective method to calculate the EIE cross sections of an atom/ion in the whole energy region is presented. We use the EIE cross sections of helium as an illustration example. The optical forbidden 1 1S–n 1S (n = 2–4) and optical allowed 1 1S–n 1P (n = 2–4) excitation cross sections are calculated in the whole energy region using the scheme that combines the partial wave R-matrix method and the first Born approximation. The calculated cross sections are in good agreement with the available experimental measurements. Based on these accurate cross sections of our calculation, we find that the ratios between the accurate cross sections and Born cross sections are nearly the same for different excitation final states in the same channel. According to this interesting property, a universal correction function is proposed and given to calculate the accurate EIE cross sections with the same computational efforts of the widely used Born cross sections, which should be very useful in the related application fields. The datasets presented in this paper are openly available at https://www.doi.org/10.57760/sciencedb.j00113.00142.

A novel caps-EEGNet combined with channel selection for EEG-based emotion recognition

Emotion recognition based on electroencephalography (EEG) is of great importance in the field of human–computer interaction. In recent years, deep learning methods, especially convolutional neural networks (CNNs), have shown great potentials in emotion recognition. However, full-channel EEG signals sometimes lead to redundant data and hardware complexity. In addition, the disadvantage of CNNs lies in its locality nature. It ignores the relationship among different channels in emotion recognition. As for channel selection, the time-domain and frequency-domain features are extracted. Then the ReliefF algorithm is used to select the initial channels with higher contribution to emotion recognition task based on these extracted features. Since the ReliefF algorithm only considers channels with high contribution, the redundancy among channels may be ignored. And thus, the max-relevance and min-redundancy (mRMR) algorithm is employed to reduce the redundancy and obtain the final channels. This algorithm is named ReliefF-mRMR. Inspired by EEGNet and capsule network (CapsNet), we combine the advantages of them and propose Caps-EEGNet. It can fully utilize the frequency and spatial information and consider the relationship among different channels. The appropriate channels selected by ReliefF-mRMR are mostly located at the frontal area, which is consistent with many other findings in relevant studies. The Caps-EEGNet method achieves average accuracy of 96.67%, 96.75% and 96.64% on valence, arousal and dominance dimensions of the DEAP dataset. And the performance on the DREAMER dataset is 91.12%, 92.6% and 93.74% accuracy on valence, arousal and dominance dimensions, respectively. Experimental results also outperform other state-of-the-art methods. Experimental results of Caps-EEGNet with 8 appropriate channels and all channels show that there is slight difference in accuracy while the computation with 8 channels is faster. In addition, the 8 appropriate channels selected by ReliefF-mRMR algorithm have a better performance than the 8 channels selected randomly. These findings are valuable for practical EEG‐based emotion recognition systems.

Time-Resolved X-ray Photoelectron Spectroscopy: Ultrafast Dynamics in CS2 Probed at the S 2p Edge.

Recent developments in X-ray free-electron lasers have enabled a novel site-selective probe of coupled nuclear and electronic dynamics in photoexcited molecules, time-resolved X-ray photoelectron spectroscopy (TRXPS). We present results from a joint experimental and theoretical TRXPS study of the well-characterized ultraviolet photodissociation of CS2, a prototypical system for understanding non-adiabatic dynamics. These results demonstrate that the sulfur 2p binding energy is sensitive to changes in the nuclear structure following photoexcitation, which ultimately leads to dissociation into CS and S photoproducts. We are able to assign the main X-ray spectroscopic features to the CS and S products via comparison to a first-principles determination of the TRXPS based on ab initio multiple-spawning simulations. Our results demonstrate the use of TRXPS as a local probe of complex ultrafast photodissociation dynamics involving multimodal vibrational coupling, nonradiative transitions between electronic states, and multiple final product channels.

Efficacy of 3D-printed assisted percutaneous transhepatic one-step biliary fistulation combined with rigid choledochoscopy for intrahepatic bile duct stones

This study evaluated the efficacy and safety of three-dimensional printing model-assisted percutaneous transhepatic one-step biliary fistulation (PTOBF) combined with rigid choledochoscopy for intrahepatic bile duct stones in patients with type I bile duct classification. The clinical data of 63 patients with a type I intrahepatic bile duct were reviewed from January 2019 to January 2023; 30 patients who underwent 3D printed model-assisted PTOBF combined with rigid choledochoscopy composed the experimental group and 33 patients who underwent simple PTOBF combined with rigid choledochoscopy composed the control group. Six indicators, including one-stage operation time and clearance rate, final removal rate, bleeding volume, channel size and complications, were observed and analyzed in the two groups. The one-stage and final removal rate in the experimental group was higher than that in the control group (P = 0.034, P = 0.014 versus control group). The time of one-stage operation, bleeding volume, and incidence of complications in the experimental group were significantly lower than those in the control group (P < 0.001, P = 0.039, P = 0.026 versus control group). Compared with simple PTOBF combined with rigid choledochoscopy, 3D printed model-assisted PTOBF combined with rigid choledochoscopy is a safer and more effective method for treating intrahepatic bile duct stones.

Tomography of Feshbach resonance states

Feshbach resonances are fundamental to interparticle interactions and become particularly important in cold collisions with atoms, ions, and molecules. In this work, we present the detection of Feshbach resonances in a benchmark system for strongly interacting and highly anisotropic collisions: molecular hydrogen ions colliding with noble gas atoms. The collisions are launched by cold Penning ionization, which exclusively populates Feshbach resonances that span both short- and long-range parts of the interaction potential. We resolved all final molecular channels in a tomographic manner using ion-electron coincidence detection. We demonstrate the nonstatistical nature of the final-state distribution. By performing quantum scattering calculations on ab initio potential energy surfaces, we show that the isolation of the Feshbach resonance pathways reveals their distinctive fingerprints in the collision outcome.

Constraints on light decaying dark matter candidates from 16 yr of INTEGRAL/SPI observations

ABSTRACT We apply the recently developed analysis of 16 yr of INTEGRAL/SPI data including a dark matter spatial template to derive bounds on dark matter candidates lighter than weakly interacting massive particles (like sterile neutrinos or axion-like particles) decaying into line or continuum electromagnetic final state channels. The bounds obtained are the strongest to date for dark matter masses between ∼60 keV and ∼16 MeV experiencing two-body decays producing photon lines.

Binary Encounter Electrons in Fast Dressed-Ion–H2 Collisions: Distorted Wave Theories and Experiment

We report measurements of double differential cross section for zero-degree binary encounter electrons emitted in collisions of 4.9 MeV and 13 MeV B(2−5)+ ions with H2 targets. The corresponding calculations based on continuum distorted-wave (CDW) theories are critically compared to the measurements. CDW in its post form exhibits a very good agreement with the measurements in all cases. The CDW theories utilized along with the well-known eikonal-initial-state (CDW-EIS) approximation are also examined and their results are compared to both the measurements and the CDW calculations. In particular, CDW-EIS using a recently proposed dynamic effective charge for the final channel projectile distortion exhibits a substantial improvement in comparison with an effective net-charge approximation.

Comparison of Nonlinear Reservoir and UH Algorithms for the Hydrological Modeling of a Real Urban Catchment with EPASWMM

This paper presents a comparative analysis of two hydrological models in the Storm Water Management Model (SWMM) software, namely, the non-linear reservoir (N-LR) and the unit hydrograph (UH), on the urban catchment of Cascina Scala, Pavia in Italy. The two models were applied for the simulation of the rainfall-runoff transformation in the 42 sub-catchments in Cascina Scala, while flow routing in the underground channels was simulated by means of the De Saint-Venant equations. A dataset of rainfall and runoff for 14 events from 2000 to 2003 was adopted for the calibration and validation of the models. The calibration was performed on 7 out of the 14 events by maximizing the fit of modeled-to-measured hydrographs in the final channel of the system. Prediction performance was assessed through different indices. Results from both models fit measured data well in terms of the total hydrograph. Whereas the time to peak was reliably predicted by both models, the N-LR was found to slightly outperform the UH in terms of total volume and peak flow prediction, though it requires a more detailed knowledge of the system for its implementation. Accordingly, the UH must be preferred in the case of a scarcity of data.

Measurement, data analysis and modeling of electromagnetic wave propagation gain in a typical vegetation environment.

This paper takes the specific environment covered by vegetation as the research object, carries out modeling and analysis, takes the large-scale fading model of wireless channel as the basis of data processing, researches the transmission law of electromagnetic wave in a typical vegetation environment, which can be divided into four situations. The signal attenuation in each case is theoretically derived and numerically simulated. From the view point of supporting vegetation environment channel, the large-scale channel measurement system is built to meet the actual needs, such as bandwidth, frequency, vegetation coverage, etc. the final vegetation environment channel model under the large-scale fading model is obtained. The results show that the path gain of four scenarios respectively are 81.3 dB, 36.5 dB, 1.6 dB, 1.5 dB, the value of path gain index is within the range of 2~3.5, four scenarios shadow fading standard deviation values are 7.1, 4.8, 10.1, 9.2, reflects the change of received power at the point caused by random factors such as reflection, absorption and scattering. In addition, the proposed channel model improves the gain about 15% compared with the tradition SUI model within vegetation coverage scene. The design process of the proposed model is carried out in the order of "studied the existing foundation → analyzed the existing problems → proposed the optimization scheme → simulation and verification results → actual measurement system". The advantage of paper's method is that, when the signal frequency, transceiver distance, antenna height and vegetation environment characteristic parameters are given, the statistical analysis results of wireless channel data are obtained. The purpose of the proposed work establishes a signal propagation prediction model under the vegetation environment, realizes a theoretical basis for channel simulation, and provides the basis of anti-fading technologies.

Wideband Synthetic-Aperture Millimeter-Wave Spatial-Channel Reference System With Traceable Uncertainty Framework

This paper describes a wideband synthetic-aperture system and the associated Fourier processing for generating high-resolution spatial and temporal estimates of the signal propagation environment in wireless communication channels at millimeter-wave frequencies. We describe how to configure the synthetic aperture system for high angular resolution by sampling the progression of signal phase across a large planar area in space. We also show how to synthesize discrete measurements of the channel frequency response taken sequentially over a wide bandwidth to create power delay profiles (PDPs) in specified angular directions with high delay resolution. We provide a rigorous uncertainty analysis that can be made metrologically traceable to fundamental physical standards. This uncertainty framework can propagate the errors inherent in the measured signals through to the final channel estimates and derived parameters such as root-mean-square delay or angular spread. We illustrate use of the system in conjunction with two different analysis tools to extract both narrowband and wideband parameter estimates from the synthetic aperture, allowing its use as a stand-alone channel sounder or as a tool for verifying the performance of wireless devices.