Direct Component Research Articles

Greenhouse Gas Emissions from Cold Chains in Agrifood Systems

Cold chains are essential components of agrifood system activities, from storage and food processing to transport, retail, and household consumption. We devise a comprehensive methodology, validated against established data, to estimate both direct (due to refrigerant use) and indirect (from energy use) greenhouse gas emissions from agrifood system cold chains, expanding previous approaches, which had focused on direct emissions only. We found that in 2022, world-total indirect emissions from energy use in cold chains were more than twice the direct component from refrigerants. This resulted in a new estimate of world-total GHG emissions from agrifood system cold chains of 1.32 Gt CO2eq in 2022, with significant growth over the past two decades (0.52 Gt CO2eq in 2000). Household consumption and food processing represented the most significant contributors to agrifood system emissions from cold chains, together representing in 2022 three-fourths of the total. These results align well with known global patterns of energy use in the refrigeration sector and highlight the importance of targeting cold chains within agrifood system with GHG emission mitigation actions.

Direct Current Ripple Component Detection Algorithm Based on Improved Variational Mode Decomposition

Background: The development of smart grids requires energy meters that enable accurate measurements. Objective: In response to the current issue where Direct Current (DC) energy meters only measure DC components and not ripple components, we propose to design a novel algorithm to achieve accurate separation of DC components and ripple components in DC signals. Methodology: This patent proposes a precise detection algorithm for ripple components. The algorithm is based on the Wavelet Decomposition combined with Flamingo Search Algorithm-Variational Mode Decomposition (WD-FSA-VMD). Firstly, we analyze the ripple characteristics in the DC signal and use the Wavelet Decomposition (WD) algorithm to separate the ripple components in the DC signal accurately. Secondly, we utilize the Flamingo Search Algorithm (FSA) to optimize the number of modal decompositions and the penalty factor in the Variational Mode Decomposition (VMD). This allows us to accurately extract the ripple components. Finally, we conducted simulation experiments comparing the improved algorithm with the original algorithm. Results: The experimental results indicate that the signal correlation coefficient obtained by the WDFSA- VMD algorithm increases by 82.64% compared to traditional VMD, and it increases by 16.72% compared to the combined Wavelet Decomposition with Whale Optimization Algorithm-Variational Mode De-composition (WD-WOA-VMD). Conclusion: The improved algorithm we proposed has good adaptability and separation performance. It is prospective for the new algorithm to provide a valuable reference to ripple detection technology.

Modeling magnetic field amplification in supernova remnants driven by laser

Abstract The origin of magnetic fields and their amplification have always been hot topics in fields such as astrophysics and high-energy-density physics. Among them, the turbulent dynamo effect is an important candidate mechanism, and the interaction between supernova remnants (SNRs) is an important carrier for studying the amplification effect of turbulent magnetic fields. In this paper, we use the radiation magnetohydrodynamic simulation program to carry out a scaling simulation study on the amplification effect of turbulent magnetic fields in the interaction of SNRs driven by powerful lasers. We investigate and compare the evolution of turbulence under different laser driving methods, different directions, and different intensities of initial external environmental magnetic fields. Here, we carefully identify the contributions of Biermann self-generated magnetic fields and environmental magnetic fields in the process of magnetic field amplification, present magnetic energy spectra, and magnetic field amplification factors, and analyze the influence of radiative cooling effect on turbulence and magnetic field evolution. The results show that the collision direction component of the environmental magnetic field dominates the process of magnetic field amplification, and the frequency spectrum of turbulence is consistent with Kolmogorov’s law. The research results are necessary for sorting out and elucidating the physical mechanism of magnetic field amplification in SNRs, and have reference significance for regulating turbulence in strong magnetic fields in the future.

Genetic parameters for direct and maternal genetic components of calving ease in Korean Holstein Cattle using animal models.

We investigated genetic parameters of calving ease (CE) using several animal models in Korean Holstein and searched for suitable models for routine evaluation of CE. Two phenotypic datasets of CE on first-parity Korean Holstein calves were prepared. DS5 and DS10 included at least 5 and 10 CE records per herd-year level and comprised 117,921 and 80,389 observations, respectively. The CE phenotypes ranged from 1 to 4, from a normal to extreme difficulty calving scale. The CE was defined as a trait of the calf. The BLUPF90+ software was used for (co)variances estimation through four animal models with a maternal effect (M1 to M4), where all models included effects of a fixed calf-sex, a fixed dam calving age (covariate), and one or more fixed contemporary group (CG) terms. The CG effects were different across models- a herd-year-season (M1, HYS), a herd-year and year-season (M2, HY+YS), a herd-year and season (M3, HY+S), and a herd and year-season (M4, H+YS). Direct heritability (h2) estimates of CE ranged from 0.005 to 0.234 across models and datasets. Maternal h2 values were low (0.001 to 0.090). Genetic correlations between direct and maternal effects were strongly negative to lowly positive (-0.814 to 0.078), further emphasizing its importance in CE evaluation models. These genetic parameter estimates also indicate slower future selection progress of CE in Korean Holsteins. The M1 fitted many levels with fewer observations per level deriving unreliable parameters, and the M4 did not account for confounded herd and animal structures. The M2 and M3 were deemed more realistic for implementation, and they were better able to account for data structure issues (incompleteness and confounding) than other models. As the pioneering study to employ animal models in Korean Holstein CE evaluation, our findings hold significant potential for this breed's future and routine evaluation development.

Automatic shock excitation system for dynamic calibration of six-axis force/torque sensor

The coupling behavior between the six-axis force/torque (F/T) sensor and the mechanical environment introduces variations in the dynamic parameters obtained through different calibration methods and devices, which poses challenges in proposing dynamic performance criteria. This paper presents a comprehensive automatic calibration system for determining the dynamic characteristics of the six-axis F/T sensor. Impulse force generators (IFGs), positioned at various orientations, apply three mutually orthogonal directional force and torque components to the sensor using a cruciform artifact. The system ensures repeatable impulse excitation by maintaining consistent spring compression in the IFG, measured by the displacement control system's grating ruler. The pulse width and frequency response function (FRF) are determined based on the response signal without measuring the input signal. The calibration frequency and the impact force magnitude can be controlled by selecting appropriate system parameters. Compared to manual impulse hammers, IFGs exhibit superior features such as high bandwidth, repeatability, and controllable force amplitude. They provide high-quality impulse excitation with calibration frequencies and forces up to 30 kHz and 2500 N or even higher, respectively. Furthermore, a linear relationship between peak value of impulse excitation and spring compression is studied to ensure effective excitation application. The consistency of dynamic calibration results of the six-axis F/T sensor verifies the effectiveness of this automatic calibration system.

An analytical model for daily‐periodic slope winds. Part 1: Surface radiation budget

AbstractThis article presents an analytical model for calculating representative daily‐periodic cycles of net surface radiation on a slope with any angle () and orientation, at any latitude and elevation (up to 2500 m), and for all seasons. Starting from the basic equations for estimating the daytime direct and diffuse components of the incoming solar radiation at the Earth's surface under clear‐sky conditions, a Fourier series expansion is derived to get an overall daily‐periodic expression, that is, covering both daytime and nighttime, which does not require data from observations, differently from most models available in the literature. Among various possible applications, this formulation is preliminary to evaluating the radiation and energy budgets driving daily‐periodic wind systems on a simple slope, as reproduced by the model presented in Part 2.

COMPARATIVE LEGAL ANALYSIS OF TAX MEASURES TAKEN IN CRISIS CONDITIONS

The world's economic and legal systems are facing a huge challenge to overcome the negative consequences imposed by recent social distortions. In 2020, what started as a health crisis quickly turned into an economic-social problem where an express response was required to ensure the functioning of social actors. This economic-social crisis was followed in a short period by new security crises with additional consequences on national systems. The response to the newly created conditions requires a multidisciplinary approach that will include measures of a health, economic, social, and security nature, adopted on the principles of legislation and expediency within the national legal systems. These measures have their own direct or indirect tax component. The purpose of this paper is to perform a legal analysis of the tax measures taken in the national systems. The scope of the research covers the member states and candidate countries for membership in the European Union. The focus is on the more recent crisis period, with particular emphasis on the COVID-19 period. The analysis primarily focuses on the legal element of the tax measures, the procedure of their implementation, and their legal nature. Also analyzed are the challenges that they have on the taxpayers and the administrative authority for their performance. The method of comparison in the paper is used to compare the similarities and differences between the tax measures in the different national systems and to detect the legal challenges imposed by the established crisis conditions. At the end, conclusions are given about the current situation and recommendations on how the establishment of tax systems should be in the future in crisis conditions.

Superluminal Proper Motion in the X-Ray Jet of Centaurus A

The structure of the jet in Cen A is likely better revealed in X-rays than in the radio band, which is usually used to investigate jet proper motions. In this paper, we analyze Chandra Advanced CCD Imaging Spectrometer observations of Cen A from 2000 to 2022 and develop an algorithm for systematically fitting the proper motions of its X-ray jet knots. Most of the knots had an apparent proper motion below the detection limit. However, one knot at a transverse distance of 520 pc had an apparent superluminal proper motion of 2.7 ± 0.4c. This constrains the inclination of the jet to be i < 41° ± 6° and the velocity of this knot to be β > 0.94 ± 0.02. This agrees well with the inclination measured in the inner jet by the Event Horizon Telescope but contradicts previous estimates based on jet and counterjet brightness. It also disagrees with the proper motion of the corresponding radio knot, of 0.8 ± 0.1c, which further indicates that the X-ray and radio bands trace distinct structures in the jet. There are four prominent X-ray jet knots closer to the nucleus, but only one of these is inconsistent with being stationary. A few jet knots also have a significant proper-motion component in the nonradial direction. This component is typically larger closer to the center of the jet. We also detect brightness and morphology variations at a transverse distance of 100 pc from the nucleus.

Modeling Gravity Gradients from Surface Gravity Anomaly Data

Gravity gradients are useful to characterize near mass anomalies since they are much more sensitive to short wavelength anomalies than gravitational accelerations. Estimating gravity gradients from surface gravity data is based on numerical implementations of solutions to geodetic boundary value problem for determination of disturbing potential. One of methods to solve this problem is least-squares collocation which is basically based on data and a defined covariance function. This study deals with estimating gravity gradient tensor components from along track surface gravity anomaly data. The Least-Squares Collocation solution is based on a stationary local covariance function defined for the disturbing potential which allows upward continuation of the observations to a desired altitude. The modeling method is evaluated in using Earth Gravitational Model 2008(EGM2008) and real airborne gravity gradiometry data collected over Southern Texas, Oklahoma region. The results show that modeled gravity gradients estimated in both on the ground and at a certain altitude have basically good agreement with EGM08 gradients. Modeled gradients including horizontal components in the east-west direction exhibit some discrepancies in comparison to the airborne gradiometry data, which may be attributed to some measurement errors in the gradient data.

Fall assessment in healthy older adults: Approach using rambling-trembling decomposition method

BackgroundThis study explored useful indices of potential fall risk in healthy older adults based on comprehensive clinical and simple quantitative posturographic measurements. MethodsA total of 64 community-dwelling older adults aged ≥65 years were classified into fallers and non-fallers based on previous fall history. After excluding two participants due to missing data, 16 and 46 participants were included in the faller and non-faller groups, respectively. We conducted major clinical measurements, including timed up and go test, 10-m walk test, functional reach test, one-leg stand test, isometric muscle strength tests, open-close stepping test, and sit-to-stand test. For quantitative posturographic measurements, participants performed standing tasks with their eyes open and closed. In the standing tasks, the time series of the center of pressure in the anteroposterior and mediolateral directions were measured and decomposed into rambling and trembling components to evaluate postural control in detail, separately. The mean velocity and root mean square of the center of pressure, rambling, and trembling were calculated and compared between fallers and non-fallers. FindingsA significant fall-related difference was found only in the mean velocity of the rambling in the anteroposterior direction; fallers displayed greater values than non-fallers, especially while standing with their eyes closed. InterpretationThe clinical measures failed to distinguish differences in fall risk, whereas the rambling component in the anteroposterior direction could detect substantial differences. The mean velocity of the rambling component could be useful as a sensitive screening biomarker for potential fall risks in healthy older adults.

Hard diffraction in SHERPA

We present the first complete simulation framework for the simulation of jet production in diffractive events at next-to leading order in QCD, matched to the parton shower. We validate the implementation in the SHERPA event generator with data from the H1 and ZEUS experiments for diffractive DIS and diffractive photoproduction. For the latter, we review different models aiming to explain the observed factorisation breaking and we argue that at NLO the direct component must also be suppressed. We provide predictions for diffractive jet production both in DIS and in photoproduction events for the upcoming EIC.

Machine learning-based prediction of statically equivalent seismic forces in pin-supported cylindrical reticulated shells

Reticulated shells exhibit complex vibrations during earthquakes, encompassing components in horizontal and vertical directions, and multiple vibration modes occur. In particular, single-layer reticulated shells with a small depth relative to their span exhibit many vibration modes, and the shapes of these modes can vary depending on the geometry. The method for rapidly setting equivalent static seismic forces remains unexplored. In response to the above background, this study proposes a novel approach for calculating the seismic forces on single-layer reticulated shells using machine learning techniques. The shells in focus are pin-supported cylindrical reticulated shells, typically for the roofs of gymnasiums used as evacuation facilities during severe earthquakes in Japan. Machine learning uses numerical analysis results for approximately 20,000 shells, with varied spans, half-open angles, and aspect ratios. A method for preprocessing the principal vibration modes as image data is proposed, after which the imaged vibration modes are predicted from the shape parameters of the shell using a neural network. The prediction accuracy is analyzed, and a method for rapidly calculating seismic loads based on combining predicted vibration modes is proposed. These seismic loads are compared with the response spectrum method results, and their effectiveness is discussed.

Calculation method of particle angular distribution based on directional probability approach in the Monte Carlo simulation

Abstract To address the limitations of narrow applicability and low computational efficiency in the existing methods for calculating particle angular distribution using Monte Carlo simulations, this paper proposes a method based on the directional probability approach. In this method, when calculating the fluence at a recording point using the directional probability approach, virtual particles are binned based on the cosine of the angle between their direction and different reference directions, enabling statistical calculation of the particle angular distribution at the recording point. The simulated one-dimensional angular distribution of particles at the recording point agrees well with the angular distribution at the recording surface, with a total fluence deviation of less than 2% and an angular distribution deviation of less than 5%. Additionally, to facilitate the coupling of particle transport simulation with other physical fields, corresponding methods have been established to statistically calculate the fluence components in different directions of the xyz coordinate system. This method can calculate one-dimensional, two-dimensional angular distributions, and different directional components of particles at any location within the radiation field, providing technical support for research in ray detection, radiation protection, nuclear radiation field analysis, and nuclear data evaluation.

Parameterization of Wave‐Induced Stress in Large‐Eddy Simulations of the Marine Atmospheric Boundary Layer

AbstractLarge‐eddy simulations (LES) of the Marine Atmospheric Boundary Layer (MABL) commonly utilize roughness length to parameterize wave effects on the sea surface. However, this method might not adequately capture the intricacies of wind‐wave interactions, especially in swell‐dominated conditions. In this study, we integrated a wave‐induced stress parameterization method into the open‐source LES code, PArallel Large‐eddy simulation Model (PALM), and assessed its performance under low wind conditions with varying wave ages and directions. Our method treats windsea effects as surface friction while employing an exponentially decaying profile to represent swell‐induced stress. We examined the model's sensitivity to wind and wave parameters and calibrated the wave damping rate values across various scenarios, leveraging data from wave‐phase‐resolved simulations and field measurements. The enhanced LES model with the proposed wave parameterization effectively reproduces wave‐influenced wind characteristics such as upward momentum flux, low‐level wind maximum, and negative wind gradients, showing good agreement with previous numerical and observational data. Moreover, our model accounts for wind‐wave misalignment scenarios by calculating each directional and spectral wave stress component individually and integrating them over the wave spectrum. We found that the swell‐induced stress is the dominant force in the wave boundary layer (WBL) with low wind speed, with its magnitude significantly varying with the wave direction relative to the wind. This variation influences the dynamic equilibrium within the WBL, modifying both wind shear and wind veer, and these effects persist up to the top of the boundary layer flow.

Effects of Rainfall Intensity, Kinetic Energy and Slope Angle to the Upslope, Downslope, and Lateral Slope Components of Splash Erosion in Hillslope Agriculture: A Case in Badiangan, Ajuy, Iloilo

This study was conducted in Barangay Badiangan, Ajuy, Iloilo City, Philippines (11°10’N, 122°58’E) to determine the effects of rainfall intensity and other rainfall-derived parameters on the directional components of splash erosion in hillslopes. There are five experimental set-ups with slope angles ranging from 0% to 48% were tested under natural rainfall conditions using a modified splash collector. The data collected shows that kinetic energy, slope, and rainfall intensity have shown significant effects on splash erosion. The models obtained using regression analysis are 𝑄𝑄𝑑𝑑𝑑𝑑𝑑𝑑=0.0093(𝐾𝐾𝐾𝐾0.80) and 𝑄𝑄𝑡 𝑡𝑡𝑡𝑡𝑡𝑡𝑡𝑡=0.060(𝐾𝐾𝐾𝐾0.107)(𝑆𝑆0.700)(𝐼𝐼200.700) . The model equation performance has been validated using the Standard Error of Estimates with values of 12 and 9.4 for splash detachment and splash transport, respectively. The constants used for kinetic energy in detachment and slope in transport align with the research by Quansah (1981) for sandy soil, which is similar (the characteristics) to the soil at our research site. Additionally, rainfall intensity, especially with a 20-min duration, generated the best model as it yielded the lowest SEE value for all cases.

An improved viscoelastic k- ε -v2-f turbulence model for intermediate and high drag reduction regimes

In this work, an improved anisotropic k-ε-v2-f model based on the finite extensible nonlinear elastic model with the Peterlin approximation for viscoelastic channel flows is proposed. This model is tested using direct numerical simulation (DNS) data for friction Reynolds numbers (Reτ) in the range of 120–1000, friction Wiesenberg numbers (Wiτ) in the range of 25–116, viscosity ratios (β) in the range of 0.6–0.9, and maximum polymer extensibility values (L2) in the range of 900–14 400. The flow characteristics of viscoelastic fluids with various parameters obtained from the new model agree well with existing DNS results. By adding closures for the flow, shear, and transverse components, the incomplete prediction of nonlinear terms from interactions between the fluctuating components of the conformation and velocity gradient tensors is improved. Compared with DNS results, these closures can fully obtain each component and significantly improve the accuracy of the flow direction component in the intermediate and high drag reduction regimes. Furthermore, the model in this paper retains the advantages of an anisotropic model, does not require a damping function, is simple to construct, and is easily extended to a variety of bounded flows.

Modeling the impact of natural roughness of tension joints on heat transport

The understanding of heat transport in fractures is crucial for mining geothermal systems. Studies of heat transport in natural fractures at scales comprised between those of laboratory experiments and those of field tracer tests are seldom. To bridge the gap, a joint surface with characteristic plumose was scanned in the field using LiDAR technology. The scanned surface was used to build a numerical model of mode 1 fracture. Fluid flow and heat transport were modeled solving the steady-state Stokes equation and assuming Fourier transport, respectively. We considered three different fracture apertures and varied systematically roughness in order to investigate the impact of plumose on fluid and heat transport. The 3D velocity flow fields were characterized by mean hydraulic aperture and by statistics on the directional components of the velocity vector. The method of temporal moments was used to extract first and second moments from temperature breakthrough curves. Heat transport parameters (local and macroscopic) were calculated from first and second moments.We show that hydraulic aperture and the longitudinal component of the velocity vector decrease with increasing roughness. The local variation of heat transport parameters is controlled by fracture roughness. For the macroscopic transport parameters, several transport regimes were identified. At low fracture aperture (i.e. 1 mm), conductive regime dominates heat transport in agreement with low Péclet numbers. In this case, fracture roughness affects the transport parameters via the loss of hydraulic aperture. With higher aperture (i.e. 3 mm) geometrical dispersion regime is dominant, roughness controlling the amplitude of transport parameters. At 5 mm aperture, transition from geometrical to Taylor dispersion occurs and the roughness tends to decrease dispersion and dispersivity according to the mean flow velocity.

Comparative analysis: Exergetic and economic assessment of LNG cold energy power generation systems with different cold utilization methods

Harnessing the cold energy inherent in LNG transportation processes can significantly mitigate energy wastage. Employing an innovative incremental analysis methodology, this study scrutinizes six LNG cold energy power generation systems, featuring a newly proposed parallel and cascade combined cycle (PAC) system. A novel approach that setting the minimum pressure within the systems higher than atmospheric levels has been adopted, for the optimal working fluid selection. The net power output (Wnet) of the direct expansion (DC) system registers at −129.51 kW, while both the Single-Stage Organic Rankine Cycle (SORC) and Combined Cycle (CC) systems yield Wnet of 2868.46 kW and 3081.46 kW with R32 as working fluid. Despite the lower available exergy extraction of the working fluid, the CC system outperforms due to its superior efficiency in converting pressure exergy into power output. Sensitivity analysis suggests the optimal Tcon in CC is limited by the normal boiling point temperature (NBPT) of working fluid, while that in SORC remains unrestricted. The maximum Wnet of two-stage Parallel Combined Cycle (PCC) and Cascade Combined Cycle (CCC) can reach 3291.65 kW and 4268.78 with the optimal working fluid combinations R32 + propane, and ethane + propane. The reason Wnet of CCC outperforms is the cascade utilization of LNG cold exergy enables the working fluid in its second stage obtains significantly 9.49 times higher amount of exergy compared to PCC. Through sensitivity analysis, while Tcon1 mostly predominates the performance of PCC, both Tcon1 and Tcon2 exert substantial influence on CCC. For the three-stage PAC, its Wnet can reach the highest 4700.82 kW with ethane + propane + propane. It is because the PAC not only utilizes LNG’s cold exergy in a cascaded manner, but also obtains the exergy from working fluid. According to economic analysis, the PAC system exhibits an advantage with the highest annul total net income (ATNI). And the CC emerges as a cost-effective choice if the irreversible losses and Wnet are not considered. According to innovatively explores about the impact of direct expansion and changes in NG outlet pressure on working fluid selection and economic feasibility, it shows the optimal combinations remain the same, and the systems incorporating a direct expansion component with lower NG outlet pressure demonstrate a more economically advantageous solution.

Establishment of DC Electric Field Measurements by Linear Dipole Type Sensor System

Nowadays, electric fields above the ground are measured mainly by so‐called ‘field mill type’ sensor systems. However, their measurements are limited to vertical field component only due to its technical constraint. Out of necessity of measurements of electric field components in arbitrary directions in any spaces, a linear dipole type DC electric field sensor system, which can be immersed within a fully uniform electric field, was developed. However, it had been remained unknown whether its sensor output is parameter‐dependent or not, and unknown whether it can provide reliable intensity value of measured electric fields or not. In order to clarify these points, test observations of natural electric fields have been conducted by means of plural sensor systems having different values of parameter. Obtained electric field intensity derived from the observed data has shown a parameter‐dependence despite that it should be constant for any parameter values. After a detailed analysis of the effect of the parameter along the equivalent electric circuit of the sensor system, a field‐calibrating formula, which can make the sensor system to be parameter‐independent, has been found. Finally, the linear dipole type DC electric field sensor system for obtaining reliable electric field intensities has been established. © 2024 The Author(s). IEEJ Transactions on Electrical and Electronic Engineering published by Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.

Evaluation of the Nonlinear Response of KCl Solution to High-Amplitude Stimulation Using a Four-Point Cylindrical Gold Electrode.

A four-electrode system and high-voltage amplitude stimulation (with a voltage of more than 1 V) are always used for nonlinear spectroscopy of biological solutions like yeast suspension. Multiple studies indicate that yeast membrane activities are the primary source of the harmonics detected from yeast suspensions. However, other investigations have demonstrated that at least part of the harmonics are mainly due to the nonlinear impedance of the electrode-electrolyte interface. Here, we want to find a mathematical model to analyze the odd harmonics generated by the interface. The KCl solution is the basis of the essential medium used in yeast culture. No study models the nonlinear behavior of the KCl solution using four-electrode. We used a sinusoidal voltage with a low frequency and a high amplitude to test an ionic solution with 1, 30, and 130 mM of potassium chloride. The voltage had no direct current component. Here, we show that the relationship between the amplitude of the excitation voltage and the third harmonic of the current can be accurately represented using the Butler-Volmer equation. Additionally, we analyze the impact of potassium chloride (KCl) concentration on the behavior of the third harmonic. This paper presents a method and model that can be used for nonlinear spectroscopy studies of biological solutions using a four-electrode system with the aim of deriving information from cells without considering the interface effect.