Study Of Behavior Research Articles

Numerical study of solidification and melting behavior of the thermal energy storage system with non-uniform metal foam and active rotation

This paper focuses on the strengthening study of the latent heat thermal energy storage (LHTES) unit and proposes a coupling strengthening method with non-uniform graded metal foam and active rotation. The non-uniform graded metal foams are employed to enhance heat conduction, and the rotation method is selected to make full use of natural convection. The solidification and melting behavior under the coupling effect of non-uniform metal foam and active rotation are numerically analyzed. The aluminum foam is partially concentrated and divided into two parts (concentrated part and diluted part) and is divided into the even-layered or uneven-layered porous structures according to the different regions area. Under the same volume of phase change material (PCM), the effects of layered forms (even-layered and uneven-layered approach), concentrated porosity, concentrated ratio, and rotational speed are performed. It can be concluded that the metal foam should concentrated near the inner tube and the uneven-layered structure can further improve the phase change heat transfer performance compared to the even-layered structure. Moreover, the thermal performance of the LHTES unit improves firstly and then decreases as the concentrated porosity, concentrated ratio, and rotational speed increase. The optimal values are obtained at 0.86 concentrated porosity, 0.3 concentrated ratio, and 0.5 rpm rotational speed. Compared with the static case with uniform metal foam, the melting time, solidification time, and total melting and solidification time can be significantly reduced by 40.30 %, 28.66 %, and 33.18 %, respectively. Similarly, the thermal energy storage rate can be correspondingly increased by 62.57 %, 40.82 %, and 54.11 %, respectively.

Understanding Macrophage-Tumor Interactions: Insights from Single-Cell Behavior Monitoring in a Sessile Microdroplet System.

Interaction between tumor-associated macrophages and tumor cells is crucial for tumor development, metastasis, and the related immune process. However, the macrophages are highly heterogeneous spanning from anti-tumorigenic to pro-tumorigenic, which needs to be understood at the single-cell level. Herein, a sessile microdroplet system designed for monitoring cellular behavior and analyzing intercellular interaction, demonstrated with macrophage-tumor cell pairs is presented. An automatic procedure based on the inkjet printing method is utilized for the precise pairing and co-encapsulation of heterotypic cells within picoliter droplets. The sessile nature of microdroplets ensures controlled fusion and provides stable environments conducive to adherent cell culture. The nitric oxide generation and morphological changes over incubation are explored to reveal the complicated interactions from a single-cell perspective. The immune response of macrophages under distinct cellular microenvironments is recorded. The results demonstrate that the tumor microenvironment displays a modulating role in polarizing macrophages from anti-tumorigenic into pro-tumorigenic phenotype. The approach provides a versatile and compatible platform to investigate intercellular interaction at the single-cell level, showing promising potential for advancing single-cell behavior studies.

Synthesis of CNT Fiber with Different Stacking-made Polyester Composite via Compression Mold: Mechanical Behavior Study

Synthesis of CNT Fiber with Different Stacking-made Polyester Composite via Compression Mold: Mechanical Behavior Study

Synthesis and Behavior Study of Basalt Fiber-Made Low-Density Polyethylene Composites Via Injection Mold

Synthesis and Behavior Study of Basalt Fiber-Made Low-Density Polyethylene Composites Via Injection Mold

Video Ethogram of Equine Social Behaviour

Equine social behaviour studies face challenges stemming from the absence of a comprehensive ethogram with unequivocal standardised definitions and the resulting limits to data comparison across studies. To address these constraints, this ethogram offers researchers a standardised framework, defining thirty-seven distinct equine social behaviours supplemented by video examples for enhanced clarity. These definitions amalgamate insights from existing ethograms and are fine-tuned through meticulous video observations, encompassing contextual cues such as distinguishing between aggressive and playful circling based on ear position and facial expressions and communicative nuances to provide a detailed representation of equine social behaviours. Video recordings complement the standardised definitions by capturing the dynamic flow and sequence of social interactions. By providing a dynamic and detailed representation, videos allow researchers to observe the temporal aspects of behaviour, including the sequence, duration, and rhythm of interactions. These detailed data are crucial for interpreting social behaviours and unravelling the complexities of equine societies. Standardized and video-illustrated definitions of equine social behaviour facilitate clear and consistent communication between researchers, enabling cross-study comparisons regarding the impact of husbandry practices and health conditions on equine social behaviour, which, in turn, can facilitate the assessment and optimisation of management practices and equine welfare.

Comparative study of thermal behavior of mango kernel fat from seven Ivorian varieties related to their chemical composition

Comparative study of thermal behavior of mango kernel fat from seven Ivorian varieties related to their chemical composition

Study of Dynamic Failure Behavior of a Type of PC/ABS Composite

PC/ABS composites are commonly used in airbag covers. In this paper, uniaxial tensile experiments of a PC/ABS composite at different temperatures and strain rates were conducted. The results showed that the temperature and loading rate affect the mechanical properties of the PC/ABS composite. As the temperature increases, the yield stress decreases and the strain at the moment of fracture increases, but the strain rate at the same temperature has a relatively small effect on the mechanical properties, which are similar to ductile materials. The experimental results were applied to the Abaqus model which considered thermal effects and the exact Johnson–Cook constitutive parameters were calculated by applying the inverse method. Based on the constitutive model and the failure analysis findings acquired by DIC, the uniaxial tensile test at the room temperature and varied strain rates were simulated and compared to the test results, which accurately reproduced the test process. The experiment on target plate intrusion of the PC/ABS composite was designed, and a finite-element model was established to simulate the experimental process. The results were compared with the experiments, which showed that the constitutive and the failure fracture strains were valid.

Numerical Study of the Thermal Behavior of a Wall Containing Phase Change Material (PCM) in a Hot and Dry Climate

Current buildings in Burkina Faso, particularly in the Sahelian zone, built with local materials are energy-intensive and sources of discomfort for the occupants. However, the role of housing is to provide man with shelter which protects him from external climatic conditions and offers him thermal comfort.  In this work, we present a numerical study of the thermal behavior of a wall containing a phase change material (PCM) in the Sahelian zone. The MCP used in this study is RT27 paraffin with a melting temperature of 27°C and a latent heat of fusion of 179kJ/kg. The equations obtained were adimensionalized and discredited by the finite element method and solved using COMSOL Multiphysics software version 5.3. To this end, we were interested on the one hand in the study of the evolution of the flow of heat and the temperature at the level of the external and internal walls of the wall. On the other hand, we studied the effect of the location of a layer of PCM mortar, simple plaster or cement plaster on the temperature of the internal wall of the wall. The results show the magnitude of heat flux and temperature is greatly reduced by the incorporation of PCM into the wall.

Study of the Physiological Behavior of Some Plants in Response to Climate Change Conditions

Study of the Physiological Behavior of Some Plants in Response to Climate Change Conditions

Experimental study of frictional behaviour of powdered soaps for wire drawing

Better understanding of frictional behaviour of powdered soaps used in dry wire drawing can lead to improvements in wire quality and large savings in energy consumption. The latter is particularly significant given the colossal amounts of energy expended in wire drawing processes. However, there is currently a very limited understanding of the subject, including a lack of quantitative data on soap friction. This is at least in part likely to be due to complex tribological behaviour of the powdered soaps, which is very different from that of lubricating oils. This paper studies frictional behaviour of sodium and calcium powdered soaps, using a ball-on-disc tribometer (ETM rig) incorporating a powder ‘scoop’, and under contact conditions pertinent to die-wire contact in wire drawing. Tests employed a WC ball and C15E steel disc to mimic die and wire materials respectively. Results show that under high sliding conditions, friction coefficient with powered soaps is remarkably low, at 0.03 and 0.04 for sodium and calcium soaps respectively. Friction generally decreased with increasing contact pressure and sliding speed. Post-test analysis of ETM specimens showed the presence of thick soap layers on the rubbed surfaces. However, in ETM tests friction was observed to sharply increase leading to the onset of scuffing, soon after the supply of soap to the contact was interrupted, suggesting that any solid deposited layers are easily removed and cannot exclusively explain the low friction. The observed trends suggest that low soap friction may be due to the ability of the soaps to form low shear stress lubricating films at high contact temperatures which are associated with the harsh conditions of high-speed and high-pressure. The results provide new insights into the frictional behaviour of powdered soaps which can be used to optimise the wire drawing processes as well as a direct input to wire deformation models.

Development of novel two-level SMA-based self-centring steel columns for seismic resilience

This paper presents an innovative two-level shape memory alloy (SMA)-based self-centring (SC) steel column, referred to as TSSSC. The TSSSC is interconnected by two series of SMA bolts, differing in diameters and lengths, to achieve multi-yielding. This is intended to fulfil multiple performance-based design objectives and augment the structural ductility of SMA elements. Utilizing the distinctive material property of phase transformation inherent in SMA, the two-level bolts can accomplish multi-level yielding in a straightforward yet effective manner. This is achieved by employing SMA elements of varying diameters in series and sequentially activating them via the material's inherent stiffness hardening. The behaviours of the TSSSC are meticulously analysed through refined finite element models (FEMs), which are corroborated by previous test results. The TSSSC demonstrates commendable multi-yielding behaviour and SC capacity during cyclic behaviour studies. In comparison to conventional SMA-based SC structures, the TSSSC exhibits markedly superior ductility, exceeding 10, whereas traditional structures typically range between 4 and 6. This enhanced ductility ensures that the TSSSC can comprehensively meet the multiple design objectives stipulated in the current performance-based seismic design. The SC and energy dissipation (ED) capacity of the TSSSC can be activated during frequent seismic events, thereby providing a safety buffer for severe earthquakes due to seismic uncertainty. Furthermore, parametric studies are conducted to identify critical design parameters, including the vertical design load, prestress in SMA bolts, and the linear stiffness ratio between the short and long bolts of the two-level SMA bolts. Design recommendations are subsequently proposed based on the findings of these parametric studies.

Dynamic study of qualitative analysis, traveling waves, solitons, bifurcation, quasiperiodic, and chaotic behavior of integrable kuralay equations

Dynamic study of qualitative analysis, traveling waves, solitons, bifurcation, quasiperiodic, and chaotic behavior of integrable kuralay equations

Evaluating Driving Factors of Environmental Behavior of Red Brick Industry Actors During the COVID-19 Pandemic

The number of COVID-19 cases in Indonesia, with a total death toll of 143 445 people as of November 1, 2021, ranked second highest in Asia, disturbing many livelihoods, including the red brick industry. This study aims to analyze the extent to which environmental behavior manifests and assess the capacity and incentive driving forces that affect the environmental behavior of actors in the red brick industry during the COVID-19 pandemic. This research was conducted through questionnaires, data processing, and analysis of descriptive and inferential data using the Statistical Package for the Social Sciences (SPSS). The results showed that the environmental behavior of actors in the red brick industry was less good (12.12%), pretty good (69.69%), and good (18.18%). This study utilized the capacity and incentive variables as driving forces. The variables that contribute to capacity can be categorized as environmental knowledge, social capital, financial capital, natural capital, and physical capital. On the other hand, the incentive variables specifically encompass market signals and government incentives. Neither of the variables have been effective in motivating environmental behavior toward a better or optimal direction. Moreover, their concurrent influence on environmental behavior was weak (8.2%). The study of human behavior focuses on the causal chain. It is, therefore, multi-dimensional, meaning that control or influence of certain factors over behavior is relatively difficult to achieve. The optimal contribution of society toward environmental protection and control has not been realized.

Detection of Gender in Crowds Using ResNet Model

The ResNet model is used in this investigation to suggest a gender detection solution for use in congested settings. Due to occlusions, varied stances, and various features, determining a person's gender in crowded surroundings may be a difficult and time-consuming job. The ResNet model, which is a deep convolutional neural network architecture, is used to solve these difficulties because of its capacity to capture detailed characteristics and its efficiency in managing deep network structures. The strategy that has been suggested entails preprocessing the input photos, sending those images through the ResNet model, and then extracting gender-related characteristics from those images. The ResNet model is made up of a number of residual blocks with skip connections, which makes it easier to learn complicated representations. After that, the learnt characteristics are input into fully linked layers, and then softmax activation is used to determine the subject's gender. The usefulness of the technique that was developed was shown by experimental findings on a large dataset, which achieved a high level of accuracy in gender determination. The use of the ResNet model helps the system to handle complicated scenarios and improves the system's ability to accurately recognize gender in situations with a large number of people. The method that has been developed has the potential to find applications in areas such as surveillance, crowd control, and the study of social behavior.

Comparative Study of Oxidation Behavior of Cr2O3 Dispersed W-Zr Alloys at 800°C, 1000°C and 1200°C Fabricated Using Powder Metallurgy

Comparative Study of Oxidation Behavior of Cr2O3 Dispersed W-Zr Alloys at 800°C, 1000°C and 1200°C Fabricated Using Powder Metallurgy

INVESTIGATION OF MORPHOLOGY, OPTICAL AND ELECTRONIC AC CONDUCTION OF THE  OLIVINE MANGANITE COMPOUND: NaMnPO4

The development of multifunctional materials is an exceptional research area, which is aimed at enhancing the versatility of materials according to their wide fields of application. Special interest was devoted here to the orthophosphate compound, in particular, the olivine NaMnPO4 material. This compound was successfully synthesized by a solid‐state method and characterized using various techniques. Preliminary room‐temperature structural analysis evidences the sample formation in the orthorhombic structure and its phase purity. The material’s morphology, analyzed by scanning electron microscopy (SEM), is identified by a spherical grain size distribution. The average grain size of the sample was estimated to be around 420 nm. Moreover, the optical investigation of UV‐visible spectroscopy has revealed that the band gap for our sample is (Eg = 2.28 eV), which shows that our compound is a potential candidate for optoelectronic applications. The electrical behavior study's main results confirm the ferroelectric character of the sample and support the aim of deepening the knowledge of the material according to its thermally stimulated conduction processes through impedance spectroscopy. Electrical studies revealed the dominant transport processes across various temperature and frequency ranges, leading to the NSPT model. The frequency dependency relates to frequency‐dispersive dielectric spectra, conduction mechanisms, and relaxation phenomena.

Mean-field study of magnetic properties and hysteresis behavior in a bilayer graphene Ising system

Using the mean-field approximation based on the Gibbs-Bogoliubov inequality for the free energy, we conducted an investigation into the magnetic properties and hysteresis behavior of a graphene Ising bilayer, where the top and bottom layers are occupied by spins σ = 3/2 and S = 5/2, respectively. The effects of exchange interactions, crystal fields, external magnetic field and temperature on the total magnetization, partial magnetizations of each layer, total magnetic susceptibility, blocking temperature and hysteresis loops of the system were thoroughly analyzed. The variations of the blocking temperature as a function of various parameters in the system’s Hamiltonian were presented. Furthermore, we demonstrated the existence of multiple hysteresis loop behaviors under specific physical conditions.

In-situ neutron diffraction study of serration-involved ultra-cryogenic deformation behavior at 15 K

This work focused on the mechanical properties and serration-involved deformation behavior of advanced alloys at 15 K. Evolution of stacking faults and ε-martensite improved the mechanical performance of CoCrNi alloys, and significant strain-induced martensite transformation of DED-SS316L led to superior strength and strain hardening. A magnitude in stress drop was governed by dislocation density, phase type, and lattice defects, irrespective of processing method. FCC {200} notably was influenced recovery behavior after stress drop, and the contribution of strain energy density by serration on tensile toughness was the greatest for HR-CoCrNi.

First-principles study of behaviors of point defects in Mo-14 Re alloy

Molybdenum alloys with rhenium additions of 14 % (Mo-14 Re) are regarded as structural materials for advanced nuclear reactors. The performance of Mo-14 Re alloy under irradiation is crucial for its application. Irradiation performance is related to the behaviors of point defects produced by irradiation. The behaviors of point defects in Mo-14 Re alloy were investigated using first-principles methods in this work. Compared with the results in pure Mo alloy, the formation energy and the migration energy of vacancy in Mo-14 Re were both reduced, and the migration energy of interstitial dumbbell increased while the formation energy decreased in Mo-14 Re. In Mo-14 Re, vacancy preferred to form and diffuse faster in Re-enriched environment. Knowing the number of Re atoms in the 1NN (first nearest neighbor) shell of the vacancy and saddle point, the vacancy formation energy and migration energy can be estimated. Since the interstitial atom has a certain orientation, the distribution of the atoms around it is anisotropic. To estimate the interstitial formation energy, it was necessary to count the number of Re atoms at the tensile and compressive sites at the 1NN shell around the interstitial. The interstitial motion was three-dimensional (3D) in Mo-14 Re. At 1200 K, the diffusion coefficient of Re atom was a little higher than that of Mo atom, which could lead to the segregation of Re atoms at defect sinks and the formation of Re-enriched phase. It is possible to investigate the longer-term evolution of microstructure using cluster dynamics (CD) or kinetic monte carlo (KMC) techniques based on these results.

Mode Shape-Based Damage Detection of Twin Skewed Bridges Based on OMA and FE Model Updating

A comparative study of the dynamic behavior of twin single-span bridges was carried out based on operational modal analysis and a linear finite element model updating with the aim of finding a potential damage indicator. The bridges are skewed, 30 m long and with prestressed concrete girders as the main support structure, but one of them were collided and suffered damage in two of its I-shape girders. Ambient vibration tests were conducted by deploying 14 uniaxial accelerometers along the sidewalks, experimental modal parameters were identified using the COVariance-driven Stochastic Subspace Identification method (SSI-COV). Six vertical modes were clearly identified for each structure. Additionally, some extra modes with non-proportional damping were identified. It was found that the modal frequencies are sensitive to the support conditions and the overall stiffness of the bridge but not to the localized girder damage, which, on the contrary, is reflected in the discrepancy in the fundamental bending mode shape amplitude between the lateral sides of the bridge, and a so-called Continuous Symmetry Measure adopted as a symmetry index seems to be a good damage indicator for this type of straight-alignment simply supported bridges, given the symmetric nature of the bending mode shapes and the asymmetric nature of the damage.