Ratio Of Energy Loss Research Articles

Strain engineering to tune the damping and magnetism in epitaxial spinel ferrite thin films by miscut substrate

Low-damping magnetic insulators like LiFe5O8 have gained considerable attention in recent years for their exceptional properties such as low energy loss and high gyromagnetic ratio, making them suitable in microwave and spintronic fields. However, due to factors such as crystalline quality and stress, the damping behavior of LiFe5O8 thin films falls below expectations. In this work, we utilize miscut substrate to modulate the structure and magnetic properties of LiFe5O8 films. We found that miscut angles can improve the crystalline quality of the film. However, a miscut angle of 6° resulted in a phase transition from tetragonal to orthorhombic in the LiFe5O8 phase. In particular, the out-of-plane ferromagnetic resonance linewidth of the orthorhombic LiFe5O8 (LFO) film was significantly reduced compared to that of the tetragonal LFO film on a non-miscut substrate, which could be attributed to the structural change. The orthorhombic LFO film also exhibited lower damping and a higher in-plane remanence ratio, indicating superior microwave magnetic properties. These findings suggest that miscut strain could be a viable method for improving the microwave magnetism of LFO films.

HT-WSO: A hybrid meta-heuristic approach-aided multi-objective constraints for energy efficient routing in WBANs

Generally, Wireless Body Area Networks (WBANs) are regarded as the collection of small sensor devices that are effectively implanted or embedded into the human body. Moreover, the nodes included in the WBAN have large resource constraints. Hence, reliable and energy-efficient data transmission plays a significant role in the implementation and in constructing of most of the merging applications. Regarded to complicated channel environment, limited power supply, as well as varying link connectivity has made the construction of WBANs routing protocol become difficult. In order to provide the routing protocol in a high energy-efficient manner, a new approach is suggested using hybrid meta-heuristic development. Initially, all the sensor nodes in WBAN are considered for experimentation. In general, the WBAN is comprised of mobile nodes as well as fixed sensor nodes. Since the existing models are ineffective to achieve high energy efficiency, the new routing protocol is developed by proposing the Hybrid Tunicate-Whale Swarm Optimization (HT-WSO) algorithm. Subsequently, the proposed work considers the multiple constraints for deriving the objective function. The network efficiency is analyzed using the objective function that is formulated by distance, hop count, energy, path loss, and load and packet loss ratio. To attain the optimum value, the HT-WSO derived from Tunicate Swarm Algorithm (TSA) and Whale Optimization Algorithm (WOA) is employed. In the end, the ability of the working model is estimated by diverse parameters and compared with existing traditional approaches. The simulation outcome of the designed method achieves 13.3%, 23.5%, 25.7%, and 27.7% improved performance than DHOA, Jaya, TSA, and WOA. Thus, the results illustrate that the recommended protocol attains better energy efficiency over WBANs.

Comparative analysis of reactive routing protocols for vehicular adhoc network communications

In the recent past, vehicular adhoc networks (VANETs) have gained a lot of importance. The routing protocols play a vital role to deliver payloads from one vehicle to another one while they are moving at relative speeds. It is a challenging task to select a routing protocol for VANETs because of the uneven distribution and high mobility of vehicles. In this paper, we have analysed the two standard reactive protocols, adhoc on-demand distance vector (AODV) and ant colony optimization (ACO). The performance comparison of AODV and ACO routing protocols has been presented in this paper. The results show AODV performed better in terms of energy consumption and routing overhead. While considering the throughput, energy loss ratio, and delay ACO has performed. ACO resulted as upperhand.

Experimental and simulation studies on ELM characteristics under a plasma current ramping up discharge on EAST

Previous experimental results show that the poloidal mode spacing of the filamentary structures increases and the dominant toroidal mode number decreases in the edgelocalized mode (ELM) rising phase with increasing plasma current. In addition, the experimental results in this paper show that the energy loss ratio of the pedestal (ΔW/Wped) decreases as the edge safety factor (q95) increases. The BOUT++ three-field two-fluid model can reproduce the experimental results and provide a possible explanation mechanism. The pedestal density plays an important role in the characteristics of filamentary structures as the current ramps up. On the one hand, the resistivity related to the pedestal density drives the instability of the peeling–ballooning mode, and the resistive effect is stronger in the high current case, making the dominant toroidal mode number lower and the corresponding poloidal mode spacing wider in the high current case. A low q95 corresponds to a high pedestal collision rate and a high pedestal energy loss ratio. On the other hand, the ELM crash process is dominated by resistivity, so the ratio of pedestal energy loss caused by ELM is not inversely proportional to the pedestal collision rate.

Hydraulic Jump Characteristics Downstream of a Compound Weir consisting of Two Rectangles with a below Semicircular Gate

Weirs are often used in laboratories, industries, and irrigation channels to measure discharge. The discharge capacity of a structure is vital for its safety and plays an important role in the combined gate-weir flow, which is a complicated phenomenon in hydropower. This study carried out experiments on a combined hydraulic structure, which included a compound sharp-crested weir made up of two rectangles along with an inverted semicircular sharp gate. Installed on a straight channel, this structure served as a control instrument. The study aimed to investigate the downstream hydraulic jump characteristics of this combined structure, specifically, the sequent depth ratio (y2/y1), the hydraulic jump height ratio (Hj/y1), the energy loss ratio through the jump (EL/Eu), and the jump length ratio (Lj/y1). The width of the upper rectangle on the weir was set at 20 cm. The width of the lower rectangle (W2) was set at 5, 7, and 9 cm, while its depths (z) were fixed at 6, 9, and 11 cm. The gate's diameters varied between 8, 12, and 15 cm. These measurements were alternated with varying initial Froude numbers (Fn1) ranging between 1.32 and 1.5. The results showed that the dimensions of both the weir and the gate influenced the hydraulic jump characteristics. Empirical formulas were developed to predict y2/y1, Hj/y1, EL/Eu, and Lj/y1 based on the differing dimensions of the combined structure. The findings and analysis of this study are limited to the range of data that were tested.

Laboratory Investigation of Energy Dissipation and Turbulent Mixing During Internal Solitary Wave Breaking on the Rough Shelf Slope

AbstractWhen internal solitary waves (ISW) propagate to the continental shelf, they typically runup and break on the forereef. This process might lead to periodic temperature drops at the reef slope, which has potential to protect coral reefs from bleaching threats. A series of laboratory experiments were conducted to investigate turbulence characteristics and energy dissipation during the ISW breaking events on the shelf slope with different bottom roughness to mimic the forereef environment. Particle image velocimetry (PIV) and planar laser‐induced fluorescence (PLIF) were coupled to obtain simultaneous high‐resolution velocity and density fields, based on which we then calculate the energy budget and turbulent dissipation rate. We found that the ISW breaking can be divided into two turbulent processes, the production of shear instability and coherent structures. Ratio of energy loss is weakened with the increase of bottom roughness and the collapse height, while the rough structure substantially enhanced the turbulent dissipation rate. The mixing efficiency is between 0.1 and 0.3, close to its maximal rate at 0.25. Our results reveal that the bottom roughness has impact on the mixing efficiency and turbulent process during the ISW breaking events. We found that rough structures at the shelf slope inhibit the mixing efficiency, especially in cases with small amplitude incline ISW. This finding may help us to better understand the reef damage and coral reef decline and support the management of coral protection strategy.

An explainable artificial intelligence based approach for the prediction of key performance indicators for 1 megawatt solar plant under local steppe climate conditions

Motivated by the growing significance of solar energy, the paper presents the findings of the maiden study on the long-term seasonal performance assessment of three PV module technologies—monocrystalline (m-Si), polycrystalline (p-Si), and amorphous silicon (a-Si) housed in a 1 MW solar plant installed at a local steppe climate in Gandhinagar, Gujarat, India using the key performance indicators (KPIs), daily power generation, final yield (Yf), reference yield (Yr), total energy loss (TEL) and performance ratio (PR). Notably, the am-Si PV modules were found to be the best performing technology, with an average PR of 71.26% and the lowest average total energy loss of 631 h during the monitored period. Moreover, PV systems have become more popular as a source of green, clean energy; yet, they have low base-load energy sustainability. Explainable AI (XAI) aids in understanding predictions made by the machine learning models. The importance of XAI lies in the comprehension and trust which is embedded into the results of machine learning algorithms. Therefore, the present work builds a comprehensive XAI model for predicting KPIs and assesses the performance of several learning algorithms using R-value, MAE, the number of iterations, and execution time. The Levenberg-Marquardt algorithm predicts the KPIs for p-Si, am-Si, and m-Si with prediction accuracies of 98.63%, 98.58%, and 90.09%, respectively. In summary, this study not only advances our understanding of PV module performance in a steppe climate context but also contributes to the broader field by integrating an XAI model for transparent and reliable predictions of the KPIs.

Application-Oriented Characterization and Analysis of Core Materials Under Medium-Frequency Condition

In medium-frequency applications, magnetic components generally operate in high-temperature conditions caused by higher power loss and more difficult heat dissipation, which results in changes in their electromagnetic characteristics. In this paper, the application-oriented characterization of the typical core materials, Mn-Zn ferrite and Fe-based nanocrystalline alloy, is comprehensively studied. The magnetic parameters under sinusoidal (5 kHz-50 kHz) and square (10 kHz) excitation from 20°C to 125°C is analyzed detailedly. Combined with the micromagnetic theory, the influence factors of electromagnetic parameters such as permeability and power factor angle are investigated. The loss variation of ferrite with temperature, flux density and frequency is explained by using the energy loss ratio. The proportion of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">h</sub> and Pdy in total loss with temperature and frequency is compared, and the loss fluctuation of nanocrystalline alloys and ferrite is analyzed. Moreover, the reasonable range of frequency that needs to consider temperature effect in practical applications is suggested. The difference between the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">B-H</i> loop bias under asymmetrical square excitation and DC bias conditions is compared and illuminated. The effectiveness and limitation of typical Steinmetz Equations considering the temperature and duty cycle effect are analyzed, and the suggestion of loss calculation is given combined with the material characteristics.

Diastolic vortex ring derangements in ischemic cardiomyopathy left ventricles: a 4D Flow MRI study

Abstract Funding Acknowledgements Type of funding sources: Private hospital(s). Main funding source(s): This work was supported by IRCCS Policlinico San Donato, a Clinical Research Hospital partially funded by the Italian Ministry of Health. Introduction Blood flowing into the left ventricle (LV) forms a 3D vortex ring starting from the free margin of mitral valve leaflets and encompassing the inflow jet. Vortex ring formation is presumed to store part of the kinetic energy of the entering jet and help directing blood flow towards the aorta [1]. Changes in vortex formation are associated to altered endocardial wall motion and LV chamber remodeling, as in case of ischemic cardiomyopathy (ICM). 4D Flow MRI is currently the unique volumetric imaging technique to assess in vivo changes of diastolic vortex ring. Purpose To characterize changes in LV diastolic vortex ring and associated energetics in a cohort of ICM patients (n = 12) vs. controls (n = 12) with comparable age. Methods 4D Flow MRI data were acquired for ICM patients presenting with anterior myocardial infarction and in healthy controls. The diastolic vortex ring was assessed at peak E-wave and at peak A-wave through the λ2 method [2]. Geometrical features of the vortex ring, e.g., circularity index (CI) and vortex orientation (α), were extracted (Figure 1). Kinetic energy (KE), rate of viscous energy loss (EL), vorticity and volume were computed for each vortex ring core; the ratios with the respective quantities computed for the entire LV were derived. Results At peak E-wave, the vortex ring was less circular (p = 0.017) and formed a smaller α with the mitral valve plane (p = 0.024) in ICM patients as compared to controls. At peak A-wave, the vortex ring core remained less circular (p = 0.027) in ICM patients, while vortex orientation remained comparable between the two groups. KE ratio, EL ratio, vorticity ratio and volume ratio significantly decreased for ICM patients at both E-peak and A-peak (Table 1). Conclusions Though ICM is primarily addressed and investigated as a systolic dysfunction, diastolic function can be deranged too, as highlighted by altered diastolic vortex ring shape and energetics.

Double loops power management circuit of pulsed triboelectric nanogenerator with enhanced efficiency at low operating voltage and its application in self-powered flue gas monitoring system

The power management circuits (PMCs) of triboelectric nanogenerators (TENGs) play a key role in developing self-powered sensing system with high energy storage efficiency. However, when the operating voltage (Vop) of PMCs meets the voltage requirement of electronic equipment (generally around 5 V), PMCs have a reduced efficiency less than 36%. Here, based on analyzing the factors affecting the efficiency of PMCs, the general methods have been proposed to improve the efficiency at a lower Vop. It is found that energy loss of diodes in PMCs is the main part in total energy loss, reaching a ratio of 61.7% at a 5 V Vop. By using rectifier diodes with lower threshold voltage and developing double loops power management circuit (DL-PMC) with less operating diodes number, the energy loss of diodes is reduced from 38.6 to 17.0 μJ, and its ratio in total energy loss at a 5 V Vop is reduced to 47.1%. Moreover, it is found that in PMCs with varied open-circuit voltage (Voc) of TENG, the increasing trend of diodes energy loss (∝Voc) is slower than that of TENG’s output energy (∝Voc2), resulting in a reduced energy loss ratio from 62.7% to 26.1% as Voc increasing from 200 to 1000 V. Finally, the measured optimal energy storage efficiency of 48.9% at 5 V Vop, the record reported so far, has been reached as using a DL-PMC with rectifier diodes and Pulsed-TENG with a Voc of 1000 V. A self-powered flue gas monitoring system consisting of Pulsed-TENG, DL-PMC, and gas sensor is developed for detecting operating status of boiler, which can transmit data every 2.5 min and will have broad applications in industry. The proposed general methods are suitable for other PMCs and will promote the development of self-powered sensing systems.

Experiment and Analysis on Friction Damage and Energy Loss Characteristics of Potatoes

In view of the problem that the research of potato friction damage is not sufficiently systematic and the characteristics of potato friction damage and energy loss are not clear, this paper investigates the initial height, potato mass, potato varieties, friction materials and temperature as experimental factors and the epidermal damage proportion as the evaluation index, filtering for significant factors by a factorial test. On this basis, the proportion of epidermal damage and the ratio of energy consumption loss were used as evaluation indicators to conduct a single factor test for significant factors. Thereby, the influence of these factors on friction damage and energy loss characteristics of potato were further investigated. The results show that the initial height, potato mass and potato varieties were the significant factors affecting the proportion of epidermal damage of potatoes. With the increase in initial height, the proportion of epidermal damage and ratio of energy consumption loss gradually increased. With the increment in potato mass, the proportion of epidermal damage gradually increased, and the energy consumption loss ratio gradually decreased. The epidermal damage proportion and energy consumption loss ratio of potato varieties were ranked as Xisen 1 &gt; Jizhang 12 &gt; Xisen 6 &gt; Xuechuanhong &gt; Netherlands 15, and Netherlands 15 &gt; Xisen 6 &gt; Xisen 1 &gt; Xuechuanhong &gt; Jizhang 12, respectively. The energy loss ratio and epidermal damage proportion were highly correlated at initial height and potato mass. A mathematical model for predicting the proportion of epidermal damage using energy consumption loss ratio is proposed: η1 = 0.8861ζ − 0.2062 (R2 = 0.8626), η2 = −0.5813ζ + 0.2394 (R2 = 0.8537).

Friction of diene rubbers on rough floors considering viscoelastic properties in the high strain range

When rubber contacts a rough surface, it undergoes cyclic deformation due to friction against asperities on the surface. The generated friction force manifests as a hysteresis term. Hysteresis is determined by energy dissipation, which is related to the viscoelastic properties of rubber. However, these properties depend on the strain and frequency of the deformation. Here I conducted a friction test of rubber. The friction coefficient was found to depend on the friction conditions (normal force, sliding velocity, and surface roughness) and the material conditions (styrene content and filler content). The strain and frequency of rubber deformation were theoretically modeled using the Greenwood–Williamson model. The modeled friction coefficient increased with the energy loss ratio calculated from the measured viscoelastic properties.

Studying the Effect of the Tangential Nonuniformity of Flow Parameters on Gas Dynamic Performances of the Nozzle Cascades of Turbine Machines

Aerodynamic efficiency of the nozzle cascades of steam and gas turbines is defined by many factors and one of them is the tangential and radial nonuniformity degree of the parameters of a spatial flow behind the cascades. The averaging of these parameters enables the determination of the integral parameters of the cascades, in particular two flow angles and the velocity angle or the kinetic energy loss coefficient. The angle that takes into account the level of the averaged radial component of the velocity defines the level of kinematic losses in the cascade. Even in the case of the cylindric boundaries of the cascade this angle differs from zero and kinematic losses decrease the cascade efficiency by 30 to 50 percent. This scientific paper gives the results of experimental investigations of the effect of the circumferential nonuniformity of the velocity and the angles of the spatial flow on kinematic losses at different radii of the nozzle cascade of the last stage of the steam turbine and the nozzle cascade of the first stage of the gas turbine. The kinetic energy loss coefficient and the coefficient of total losses were suggested as the integral characteristics of the cascades. In the case of cylindric boundaries of the stage the total loss-to-kinetic energy loss ratio is noticeably decreased during the transition from the average zone to the zone of end losses. However, in the peripheral zone of the nozzle cascade of the last stage of steam turbine total losses are three times higher than kinetic energy losses due to the fact that the radial component of the velocity behind the cascade is much higher than the flow rate component and the level of the losses of kinetic energy is not high.

MORPHOLOGY OF LANDSCAPES AND GEOPHIZICAL INDICATORS OF ECOSYSTEM OF THE KHMELNYTSKE PRYDNISTERIA

The aim. Geochemical indicators are used to assess the anthropogenic impact on landscapes. Normality geophysical indicators are used much less, although since ancient times scientists have proposed indicators of heat and water balances, the ratio of energy losses to evaporation and heat exchange, hydrothermal coefficients of heat and moisture to characterize natural areas and smaller natural complexes.&#x0D; Methodology. The analysis of published and cartographic materials, landscape schemes and maps of physical and geographical zoning and field route observations made it possible to identify the morphological structure of landscapes in the territory of Khmelnytske Prydnistrovia. Data on geophysical parameters of the zonal types of plains landscapes are systematized. The parameters for the assess of anthropogenic impacts are suggested for the landscapes species.&#x0D; Results. The article contains tables of the landscape structure by the ratio of the areas of certain types of areas and agroclimatic indicators for 4th natural regions of the Khmelnytske Prydnistrovia, geophysical and biogeophysical indicators for landscape zones and subzones. For the Gorodoksky, Ushitsky, Toltrovy and Zhvanchitsky natural regions, indicators of the ratio of heat and moisture were determined with an increase in the sum of temperatures of the active growing season from 2500 ° C to 2780 ° C in the Dniester valley, a decrease in the GTC from north to south from 1.5 to 1.2 and variations in the moisture coefficient in range typical for the southern forest-steppe (0.8-0.7). The duration of the frost-free period increases from 160 days in the Gorodok area to 178 days in the Dniester valley on average over a hundred years of observations.&#x0D; Originality and practical value. All indicators are a normative basis for comparison with the corresponding data in modern landscape complexes that have been changed or transformed by economic activities. For different types of active surfaces (water, meadow, field, and forest tracts), the albedo, absorbed radiation, the ratio of energy expenditure on evaporation, and turbulent heat exchange with the atmosphere are given.&#x0D; Conclusion. When conducting environmental impact assessment and monitoring, when identifying violations of natural processes, geophysical indicators are needed to assess the environmental impact (EIA). Preservation and protection of the natural ecological framework, its study, and research of processes and patterns of migration of matter and energy at the local level is possible only in stationary conditions of reserves and sanctuaries. Elucidation of causal relationships in natural processes, pathways of micronutrient migration and distribution and redistribution of radionuclides, and study of the intensity of anthropogenic impact on the formation and functioning of local level geosystems are necessary to create a database of actual material.&#x0D; The analysis of the landscape structure by the area of certain types of localities showed the differences between the natural areas of Khmelnytskyi Transnistria, which are also manifested in agroclimatic resources. Different types of active surfaces (water, meadow, field, and forest tracts) are characterized by individual indicators of albedo, the ratio of absorbed radiation, energy consumption for evaporation, and turbulent heat exchange with the atmosphere.&#x0D; Geophysical and biogeophysical indicators allow to assess changes in the factors of functioning of natural landscapes, so it is advisable to assess the natural-technical and natural-anthropogenic complexes of the rank of localities, types of landscapes and physical-geographical provinces. Geophysical indicators are the normative basis for comparison with the corresponding.&#x0D; Key words: geophysical indicators, the structure of landscapes, Khmelnytske Prydnisteria, agroclimatic dates, ecology.

Observation of anomalous spectral downshifting of waves in the Okhotsk Sea Marginal Ice Zone.

Waves in the Marginal Ice Zone in the Okhotsk Sea are less studied compared to the Antarctic and Arctic. In February 2020, wave observations were conducted for the first time in the Okhotsk Sea, during the observational program by Patrol Vessel Soya. A wave buoy was deployed on the ice, and in situ wave observations were made by a ship-borne stereo imaging system and Inertial Measurement Unit. Sea ice was observed visually and by aerial photographs by drone, while satellite synthetic aperture radar provided basin-wide spatial distribution. On 12 February, a swell system propagating from east northeast was detected by both the stereo imaging system and the buoy-on-ice. The wave system attenuated from 0.34 m significant wave height to 0.25 m in about 90 km, while the wave period increased from 10 s to 15-17 s. This anomalous spectral downshifting was not reproduced by numerical hindcast and by applying conventional frequency-dependent exponential attenuation to the incoming frequency spectrum. The estimated rate of spectral downshifting, defined as a ratio of momentum and energy losses, was close to that of uni-directional wave evolution accompanied by breaking dissipation: this indicates that dissipation-driven nonlinear downshifting may be at work for waves propagating in ice. This article is part of the theme issue 'Theory, modelling and observations of marginal ice zone dynamics: multidisciplinary perspectives and outlooks'.

Analysis of Energy Loss Characteristics of Vertical Axial Flow Pump Based on Entropy Production Method under Partial Conditions.

The energy loss of the vertical axial flow pump device increases due to the unstable internal flow, which reduces the efficiency of the pump device and increases its energy consumption of the pump device. The research results of the flow loss characteristics of the total internal conduit are still unclear. Therefore, to show the internal energy loss mechanism of the axial flow pump, this paper used the entropy production method to calculate the energy loss of the total conduit of the pump device to clarify the internal energy loss mechanism of the pump device. The results show that the energy loss of the impeller is the largest under various flow conditions, accounting for more than 40% of the total energy loss of the pump device. The variation trend of the volume average entropy production and the energy loss is similar under various flow coefficients (KQ). The volume average entropy production rate (EPR) and the energy loss decrease first and then increase with the increase of flow, the minimum volume average entropy production is 378,000 W/m3 at KQ = 0.52, and the area average EPR of the impeller increases gradually with the increase of flow. Under various flow coefficient KQ, the energy loss of campaniform inlet conduit is the smallest, accounting for less than 1% of the total energy loss. Its maximum value is 63.58 W. The energy loss of the guide vane and elbow increases with the increase of flow coefficient KQ, and the maximum ratio of energy loss to the total energy loss of the pump device is 29% and 21%, respectively, at small flow condition KQ = 0.38. The energy loss of straight outlet conduit reduces first and then increases with the increase of flow coefficient KQ. When flow coefficient KQ = 0.62, it accounts for 27% of the total energy loss of the pump device, but its area average entropy production rate (EPR) and volume average entropy production rate (EPR) are small. The main entropy production loss in the pump device is dominated by entropy production by turbulent dissipation (EPTD), and the proportion of entropy production by direct dissipation (EPDD) is the smallest.

Optimization Design of Vibration Reduction Structure of Driving Sprocket Based on Niche Adaptive Genetic Algorithm

To improve the damping performance of driving sprocket of crawler construction vehicle, this paper replaces the tubular constraint ``double damping layer'' structure (TCDDS) with a ``damping layer + stand-off-layer'' structure, and the dynamics analysis of the structure is carried out under multiple working conditions. By analyzing the dynamic performance of the vibration damping structure under different working conditions, the optimal laying position of the damping layer and the stand-off-layer is discussed. Furthermore, under the condition that the total thickness of the tubular stand-off-layer sandwiched structure(TSSS) remains constant and both the stand-off- layer and damping layer do not exceed the allowable stress and strain, the energy loss ratio per unit period is taken as the optimization goal, and based on niche-adaptive genetic algorithm, the design variables(thickness of base layer, constraint layer, stand-off-layer and damping layer, material elastic modulus and loss factor of stand-off-layer and damping layer) are optimized by ANSYS and MATLAB. The optimization results show that the maximum displacement and stress of the damping layer and stand-off-layer of the structure after optimization are greatly reduced compared with those before optimization, the maximum strain increases from 15.35% to 22.55%, and the energy loss ratio increases from 0.2914 to 0.5418, which improves the vibration reduction effect of the structure. The theories and methods of this paper can provide a certain reference for the vibration damping design of heavy-duty crawler vehicles, and have a certain reference value for the application of genetic algorithm optimization in the structural design of construction vehicles.

Irradiation-induced microstructural transformations in UO2 accelerated upon electronic energy deposition

The combination of electronic and nuclear energy deposition can have an effect on the defect production and evolution that is not simply the sum of both independent contributions. In nuclear reactors, the fuel is exposed to the irradiation of several particles such as the fission fragments (FF) whose electronic to nuclear energy loss ratio evolves along their path. To understand the impact of this energy-loss coupling on the fuel microstructure, single and dual-beam ion irradiations of uranium dioxide (UO2) were carried out. The damage evolution was investigated by Raman spectroscopy analysis correlated with Transmission Electronic Microscopy observations. It was found a significant acceleration effect of the electronic energy dissipation on the formation and evolution of defects induced by the nuclear energy deposition. The magnitude of this acceleration was shown to depend on both the electronic energy loss level and the microstructure at the moment when the coupling occurs.

Comparative study of the MeV ion channeling implantation induced damage in 6H-SiC by the iterative procedure and phenomenological CSIM computer code

Due to its unique material properties, such as extreme hardness and radiation resistance, silicon carbide has been used as an important construction material for environments with extreme conditions, like those present in nuclear reactors. As such, it is constantly exposed to energetic particles (e.g., neutrons) and consequently subjected to gradual crystal lattice degradation. In this article, the 6H-SiC crystal damage has been simulated by the implantation of 4 MeV C3+ ions in the (0001) axial direction of a single 6H-SiC crystal to the ion fluences of 1.359 1015 cm-2, 6.740 1015 cm-2, and 2.02 1016 cm-2. These implanted samples were subsequently analyzed by Rutherford and elastic backscattering spectrometry in the channeling orientation (RBS/C &amp; EBS/C) by the usage of 1 MeV protons. Obtained spectra were analyzed by channeling simulation phenomenological computer code (CSIM) to obtain quantitative crystal damage depth profiles. The difference between the positions of damage profile maxima obtained by CSIM code and one simulated with stopping and range of ions in matter (SRIM), a Monte Carlo based computer code focused on ion implantation simulation in random crystal direction only, is about 10%. Therefore, due to small profile depth shifts, the usage of the iterative procedure for calculating crystal damage depth profiles is proposed. It was shown that profiles obtained by iterative procedure show very good agreement with the ones obtained with CSIM code. Additionally, with the introduction of channeling to random energy loss ratio the energy to depth profile scale conversion, the agreement with CSIM profiles becomes excellent.

Deep learning jet modifications in heavy-ion collisions

Jet interactions in a hot QCD medium created in heavy-ion collisions are conventionally assessed by measuring the modification of the distributions of jet observables with respect to the proton-proton baseline. However, the steeply falling production spectrum introduces a strong bias toward small energy losses that obfuscates a direct interpretation of the impact of medium effects in the measured jet ensemble. Modern machine learning techniques offer the potential to tackle this issue on a jet-by-jet basis. In this paper, we employ a convolutional neural network (CNN) to diagnose such modifications from jet images where the training and validation is performed using the hybrid strong/weak coupling model. By analyzing measured jets in heavy-ion collisions, we extract the original jet transverse momentum, i.e., the transverse momentum of an identical jet that did not pass through a medium, in terms of an energy loss ratio. Despite many sources of fluctuations, we achieve good performance and put emphasis on the interpretability of our results. We observe that the angular distribution of soft particles in the jet cone and their relative contribution to the total jet energy contain significant discriminating power, which can be exploited to tailor observables that provide a good estimate of the energy loss ratio. With a well-predicted energy loss ratio, we study a set of jet observables to estimate their sensitivity to bias effects and reveal their medium modifications when compared to a more equivalent jet population, i.e., a set of jets with similar initial energy. Finally, we also show the potential of deep learning techniques in the analysis of the geometrical aspects of jet quenching such as the in-medium traversed length or the position of the hard scattering in the transverse plane, opening up new possibilities for tomographic studies.