Critical Behavior Research Articles

Viscoelastic characterization of coating layers by ultrasonic interference and critical attenuation

This study proposes a characterization technique for a viscoelastic coating layer on a metal substrate immersed in water based on ultrasonic interference and critical attenuation phenomena. Theoretical analysis shows that the reflection spectrum for the normal incidence wave has local minima at the resonance frequencies of the coating layer, which provide its elastic property if the layer thickness is given a priori. Furthermore, it is revealed that the lower envelope of the reflection spectrum takes a minimum, whose frequency can be related to the critical attenuation condition. This feature implies a possibility that the viscous property of the coating material can be estimated by similarly measuring a characteristic frequency to the estimation of the elastic property. Two bonded specimens consisting of polycarbonate (PC) sheets and metal substrates were prepared to validate the proposed method. The reflection spectra measured for the normal wave incidence showed multiple local minima and critical attenuation, which are predicted to appear by theoretical predictions. The wave velocities and loss factors of PC estimated from the two specimens are in fair agreement with the properties shown in the previous paper. This result demonstrates that the ultrasonic interference and critical attenuation behavior can be applied to the characterization of the viscoelastic coating layers.

Eccentrically compressed behavior of UHPC columns considering the P-delta effect

Eccentric compression is a critical behavior observed in arches and columns, particularly in structures constructed with ultra-high performance concrete (UHPC). Compared to normal concrete structures, those made with UHPC exhibit distinct behaviors that need to be clearly investigated. This study comprehensively investigates UHPC columns under eccentric compression load through experimental study and theoretical analysis. Various experimental parameters, including slenderness ratio, eccentricity distance, fiber content, and stirrup ratio, were examined across 26 UHPC columns. Failure modes were evaluated using digital image correlation (DIC) methods. The load-displacement responses indicated that slender columns subjected to significant eccentricity exhibited load decreases during yielding stages, whereas short columns experienced load increases. This discrepancy in yielding stages was attributed to P-delta effects. In addition, theoretical models were developed to determine the ultimate bearing capacity of columns experiencing compression-controlled and tension-controlled failures, considering the P-delta effect caused by the different slenderness ratios. The moment magnifying coefficients for UHPC were calibrated based on theoretical analyses of the limit curvature of eccentric compression members. The proposed theoretical models agreed well with the experimental results, with an average ratio of 1.02. The second-order effect for the case of UHPC short column with a slenderness ratio of 5 can be ignored as per Eurocode 2, which is less than 10 % of the corresponding first-order effect.

Impact of Climate, Cynicism and Culture on Organizational Citizenship Behavior with Intervening Impact of Job Embeddedness

The standoff between management and the young doctor's organization (YDA) caused by periodic strikes has had major consequences for patients who do not receive medical attention when needed. This includes the stoppage of treatment in public hospital emergencies, which frequently results in patient deaths, reflecting a negative image of public hospitals. Analysis of the procedural imbalance and relationships between several organizational environment, culture, cynicism, citizenship behavior, and job embeddedness criteria in public-sector hospitals is the goal of this study. However, information gathered from the young doctors at Lahore's Public Sector Health Hospitals was necessary for this study to be successful. To compute the results, several statistical procedures were used, including factor analysis, regression, correlation, and reliability analysis. To examine the findings, information was gathered from 146 responders, who were young physicians. This study found that whereas JE mediates the association between organizational climate, cynicism, culture, and citizenship behavior among young doctors in Lahore's public sector hospitals, organizational climate has a considerable impact on OCB while organizational cynicism and culture have a small impact.

Investigation of the magnetocaloric effect and critical behavior of the perovskite La0.65Ca0.35−xBaxMnO3 (x=0, 0.1, 0.2, 0.3)

Polycrystalline samples of La[Formula: see text]Ca[Formula: see text]BaxMnO3 (x = 0, 0.1, 0.2, 0.3) were prepared using a conventional solid-state reaction method. The prepared samples demonstrated good single-phase quality, characterized by a space group of Pbnm. There was a significant increase in the relative cooling power (at 5[Formula: see text]T), with values as follows: RCP[Formula: see text][Formula: see text]J[Formula: see text]⋅[Formula: see text]kg[Formula: see text], RCP[Formula: see text][Formula: see text]J[Formula: see text]⋅[Formula: see text]kg[Formula: see text], RCP[Formula: see text][Formula: see text]J[Formula: see text]⋅[Formula: see text]kg[Formula: see text], and RCP[Formula: see text][Formula: see text]J[Formula: see text]⋅[Formula: see text]kg[Formula: see text]. It is noteworthy that the sample with a doping level of x = 0.2 underwent a transition from a first-order phase transition to a second-order phase transition. The critical behavior of the x = 0.2 and 0.3 samples was analyzed using modified Arrott plots and the Kouvel–Fisher method to determine critical exponents. The results obtained from both methods were in close agreement, indicating that the critical behavior of the x = 0.2 and 0.3 samples can be described by the mean field model.

Investigation of pad radius effects on multiaxial fretting fatigue behavior of al2024 alloy

Fretting fatigue, a critical phenomenon prevalent in engineering applications, occurs at the interface of contacting surfaces under cyclic loading, presenting significant challenges. The advent of Finite Element Analysis (FEA) has transformed the investigation of fretting fatigue by offering detailed insights into stress distributions and fatigue damage mechanisms. This study delves into the impact of pad radius on the fretting fatigue behavior of Al2024 alloy using FEA, with a focus on hot spot analysis and the Smith-Watson-Topper (SWT) criterion. The analysis aims to validate numerical results against analytical findings and explore the role of pad radius in determining contact behavior, fatigue life, and hot spot locations. By incorporating "fe-safe" software, computations are streamlined, facilitating efficient comparison of different fatigue initiation criteria. The results demonstrate that variations in pad radius significantly influence fretting fatigue behavior. Larger pad radii tend to distribute stresses more uniformly across the contact interface, resulting in reduced fatigue damage and longer fatigue life compared to smaller pad radii. Hot spot analysis reveals that smaller pad radii concentrate stresses at specific regions, accelerating fatigue damage initiation. The findings contribute to a deeper understanding of fretting fatigue mechanisms, shedding light on the importance of pad radius in designing more durable engineering components. Through professional scientific methodology, this study provides valuable insights into optimizing pad design to mitigate fretting fatigue and enhance the reliability of mechanical systems.

Emergent tetragonality in a fundamentally orthorhombic material.

Symmetry plays a key role in determining the physical properties of materials. By Neumann's principle, the properties of a material remain invariant under the symmetry operations of the space group to which the material belongs. Continuous phase transitions are associated with a spontaneous reduction in symmetry. Less common are examples where proximity to a continuous phase transition leads to an increase in symmetry. We find signatures of an emergent tetragonal symmetry close to a charge density wave (CDW) bicritical point in a fundamentally orthorhombic material, ErTe3, for which the two distinct CDW phase transitions are tuned via anisotropic strain. We first establish that tension along the a axis favors an abrupt rotation of the CDW wave vector from the c to a axis and infer the presence of a bicritical point where the two continuous phase transitions meet. We then observe a divergence of the nematic elastoresistivity approaching this putative bicritical point, indicating an emergent tetragonality in the critical behavior.

Saturation Equation: An Analytical Expression for Partial Saturation during Wicking Flow in Paper Microfluidic Channels.

The design and fabrication of paper-based microfluidic devices is critically dependent on modeling fluid flow through porous paper membranes. A commonly observed phenomenon is partial saturation, i.e., regions of the paper membrane not being filled completely due to pores of different sizes. The most comprehensive model to date of partial saturation during wicking flow in paper is the Richards equation. However, the solution to the Richards equation requires numerical solvers like COMSOL, which makes it largely inaccessible to the paper microfluidics and lateral flow assay community. There is therefore a need for a simple and appropriate model of partial saturation in paper membranes, easily usable by the wider research community. In the current work, we present an approach to model paper membranes as a bundle of parallel capillaries whose radii follow a two-parameter log-normal distribution. Application of the Washburn equation to the bundle provides a distribution of fluid fronts, which can be used to calculate saturation. Using this approach, we developed the "saturation equation"─an explicit analytical expression to calculate saturation as a function of space and time in 1D wicking flow. Experimentally obtained data for spatiotemporal saturation for four different paper materials were fit to this analytical model to obtain parameters for each material. Results obtained from this analytical model match well with both experimental data and numerical results obtained from the Richards equation. The availability of an explicit analytical expression for partial saturation will enable incorporation of the critical phenomenon of partial saturation in the design of paper microfluidic devices.

The Measured Flow at the Inlet of a Francis Turbine Runner Operating in Speed No-Load Condition

Abstract For Francis turbines, speed-no-load (SNL) represents one of the most detrimental operating conditions, marked by significant pressure and strain fluctuations on the runner. Mitigating these fluctuations necessitates a comprehensive understanding and characterization of the flow phenomena responsible for their generation. This paper presents an experimental investigation of the flow at the inlet of a Francis turbine runner model operating in speed-no-load condition using high-speed stereoscopic and endoscopic particle image velocimetry (PIV). The measurements are made in a radial-azimuthal plane that covers the vaneless space and a large region in the interblade channel. This study marks the first-time measurement of critical flow phenomena at this operating point, performed in the runner. Instantaneous and average velocity fields are analyzed, along with other statistical data. The results not only confirm the stochastic nature of the flow at speed-no-load but also highlight the general structure of the flow observed in other studies. The high velocity fluctuations on the suction side are associated with a backflow extending into the vaneless space and a circulation zone occasionally generated by this backflow. Both phenomena are frequently present, but fluctuate stochastically. Additionally, two other circulation zones intermittently form on the pressure side of the blades. The presence of vortices, smaller than the circulation zones, near the blade's leading edge correlates with the backflow intensity.

Amyloid Mimicking Assemblies Formed by Glutamine, Glutamic Acid, and Aspartic Acid.

The aggregation of amino acids into amyloid-like structures is a critical phenomenon for understanding the pathophysiology of various diseases, including inborn errors of metabolism (IEMs) associated with amino acid imbalances. Previous studies have primarily focused on self-assembly of aromatic amino acids, leading to a limited understanding of nonaromatic, polar amino acids in this context. To bridge this gap, our study investigates the self-assembly and aggregation behavior of specific nonaromatic charged and uncharged polar amino acids l-glutamine (Gln), l-aspartic acid (Asp), and l-glutamic acid (Glu), which have not been reported widely in the context of amyloid aggregation. Upon aging these amino acids under controlled conditions, we observed the formation of uniform, distinct aggregates, with Gln forming fibrillar gel-like structures and Glu exhibiting fibrous globular morphologies. Computational simulations validated these findings, identifying Gln as the most potent in forming stable aggregates, followed by Glu and Asp. These simulations elucidated the driving forces behind the distinct morphologies and stabilities of the aggregates. Thioflavin T assays were employed to confirm the amyloid-like nature of these aggregates, suggesting their potential cytotoxic impact. To assess toxicity, we performed in vitro studies on neural cell lines and in vivo experiments in Caenorhabditis elegans (C. elegans), which demonstrated measurable cytotoxic effects, corroborated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and heat shock survival assays. Importantly, this study fills a critical gap in our understanding on the role of nonaromatic amino acids in amyloidogenesis and its implications for IEMs. Our findings provide a foundation for future investigations into the mechanisms of diseases associated with amino acid accumulation and offer potential avenues for the development of targeted therapeutic strategies.

Do multi-channel use and online engagement matter for critical literacy and information verification behaviors? Comprehensive comparisons of six generations from before 1954 (war generation) to generation Z (after 1997)

The prevalence of multi-channel information consumption, which involves the simultaneous engagement with multiple information sources across various platforms, underscores the urgent need for research on its effects as it profoundly influences how individuals seek, evaluate, and interact with information, ultimately shaping their information-related choices and behaviors. Using an innovative empirical method to extract a set of latent groups based on individuals' multi-channel practices, the study examined the role of channel plurality relative to how people evaluate and consume information online. Importantly, this research examined how conditions of the critical literacy and practices can be configured to benefit six distinct generational groups, ranging from the youngest generation group (1990s) to the oldest generation (1950s). Based on results of a nationally representative survey (N = 10,032), the current research demonstrated how individuals’ channel plurality contributes to their critical literacy and information verification behaviors. Finally, this study identified differences in information practices manifested in six generational groups. In the end, this study bridged two streams of research, new media literacy and the digital divide, and discussed how different educational and regulatory approaches can be made to encourage critical information consumption in an increasingly digitized network environment.

Fatigue prediction through quantification of critical defects and crack growth behaviour in additively manufactured Ti-6Al-4V alloy

The study presents a methodology for predicting the fatigue life and identifying critical defects in additively manufactured (AM) Ti-6Al-4V alloy processed via laser powder bed fusion (L-PBF). Predictions were made on L-PBF Ti-6Al-4V alloy in two conditions: as-built and heat-treated by using X-ray μ-Computed Tomography (μ-CT) for the quantification of the defects and fatigue crack growth (FCG) data. For validation, fatigue life predictions were made on the same specimens on which μ-CT was conducted prior to fatigue testing. FCG and fatigue tests (S-N) highlighted differences in the performance between the as-built and heat-treated conditions: the as-built condition had a lower threshold stress intensity factor range (ΔKth) of 2.16 MPa m1/2 than that of the heat-treated condition, 4.96 MPa m1/2. Differences in fatigue limit were attributed to differences in ΔKth in as-built and heat-treated specimens. To gain mechanistic understanding of these differences near ΔKth cracks were examined using Electron Backscatter Diffraction - Kernel Average Misorientation (EBSD-KAM). It was found that upon heat treatment, the dislocation density increased around near threshold fatigue cracks. Increases in ΔKth are attributed to the increases in β-phase content and α-lath thickness caused by heat treatment.

Critical Behaviors of van Der Waals Itinerant Ferromagnet Fe3.8GaTe2.

The critical behavior of the van der Waals ferromagnet Fe3.8GaTe2was systematically studied through measurements of isothermal magnetization, with the magnetic field applied along thec-axis. Fe3.8GaTe2undergoes a non-continuous paramagnetic to ferromagnetic phase transition at the Curie temperatureTc∼355K. A comprehensive analysis of isotherms aroundTcutilizing the modified Arrott diagram, the Kouvel-Fisher method, the Widom scaling law, and the critical isotherm analysis yielded the critical exponent ofβ=0.411,γ=1.246, andδ=3.99. These critical exponents are found to be self-consistent and align well with the scaling equation at high magnetic fields, underscoring the reliability and intrinsic nature of these parameters. However, the low-field data deviates from the scaling relation, exhibiting a vertical trend whenT<Tc. This discrepancy suggests the occurrence of a first-order phase transition in the crystal under a low magnetic field whenT<Tc. Mössbauer spectra were employed to provide insights into the critical behaviors of magnetic moments at different sites, including (Fe1)A, (Fe1)B, and Fe2. The results are consistent with the isothermal magnetization analysis. Additionally, the renormalization group theory analysis reveals that the spin coupling within the Fe3.8GaTe2crystal follows the three-dimensional Heisenberg ({d:n}={3:3}) type with long-range magnetic and exchange interaction decays with a distance asJ(r) ≈r-4.80.

Critical Exponents and Universality for Fractal Time Processes above the Upper Critical Dimensionality

We study the critical behaviors of systems undergoing fractal time processes above the upper critical dimension. We derive a set of novel critical exponents, irrespective of the order of the fractional time derivative or the particular form of interaction in the Hamiltonian. For fractal time processes, we not only discover new universality classes with a dimensional constant but also decompose the dangerous irrelevant variables to obtain corrections for critical dynamic behavior and static critical properties. This contrasts with the traditional theory of critical phenomena, which posits that static critical exponents are unrelated to the dynamical processes. Simulations of the Landau–Ginzburg model for fractal time processes and the Ising model with temporal long-range interactions both show good agreement with our set of critical exponents, verifying its universality. The discovery of this new universality class provides a method for examining whether a system is undergoing a fractal time process near the critical point.

Sustainable future of construction: the potential of concrete with basalt mini-bars as reinforcement

The paper concerns the influence of basalt minibars on the subcritical and critical behaviour of test specimens made of concrete with low-emission cement. Low-emission cement produces lower emissions of greenhouse gases and other pollutants than traditional cement. Analyses were conducted on changes in fracture mechanics parameters depending on the content of microfibers in the concrete mix (0, 2, 4, 8 kg/m³), the type of cement used, and the water-to-cement ratio (w/c). It was demonstrated that concrete reinforced with basalt microfibers exhibits increased resistance to crack initiation and propagation. An increase in the stress intensity factor was observed for CEMI 42.5R concretes at w/c=0.5 by 27%, at w/c =0.4 by 62%, and for CEM II 42.5R/A-V concretes at w/c=0.5 by 29%, and at w/c=0.4 by as much as 30%. It was shown that the addition of microfibers to concrete made with low-emission cement significantly increases the mechanical parameters of this material.

An in-depth examination of management interaction through employee voice dynamics in human resource management

Voice is a critical employee behavior that promotes ideas, concerns and ideas throughout the company. It is a frequent technique that learning the obstacles of leadership and issues that can affect the functioning of the corporation. In this paper, our primary goal of the research on employee voices, determine fields and the research findings on employee voice can be utilized as well as modified to be applied in other categories that illustrate the result in a more broad conception of employee voice. This review includes the fields of employee voice and Organizational Behavior (OB) coupled with Human Resource Management/Employment Relations (HRM/ER). It maintains by indicating the field's conceptions and assessments of employee voices that are distinct from one another. The impact of direct opinions from superiors, direct voice involvement and the mediating function that trust assumes are in those interactions. Based on significance, technique, process and voice management, it identifies their similarities and variations.

Ultracold atomic spin mixtures in ultrastable magnetic field environments

Abstract Ultracold atomic spin mixtures develop rich and intriguing magnetic properties when external radiation coherently couples different spin states. In particular, the coupled mixture may acquire a critical behavior when the spin interactions equal the coupling energy. &amp;#xD;However, atomic mixtures generally feature a relatively high sensitivity to magnetic fields that can set a limitation to the observable phenomena.&amp;#xD;In this article, we present an overview of experimental studies of magnetism based on superfluid multicomponent gases in an ultrastable magnetic field environment, which recently became available.

Chaos near to the critical point: butterfly effect and pole-skipping

We study the butterfly effect and pole-skipping phenomenon for the 1RCBH model which enjoys a critical point in its phase diagram. Using the holographic idea, we compute the butterfly velocity and interestingly find that this velocity can probe the critical behavior of this model. We calculate the dynamical exponent of this quantity near the critical point and find a perfect agreement with the value of the other quantity’s dynamical exponent near this critical point. We also find that at special points, namely the (ω⋆=iλL,k⋆=iλL/vB),\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$(\\omega _\\star = i \\lambda _L, \\, k_\\star = i\\lambda _L/v_B),$$\\end{document} where λL\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\lambda _L$$\\end{document} and vB\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$v_B$$\\end{document} are Lyapunov exponent and butterfly velocity respectively, the phenomenon of pole-skipping appears which is a sign of a multivalued retarded Green’s function. Furthermore, we observe that vB2≥cs2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$v_B^2 \\ge c_s^2$$\\end{document} at each point of parameter space of the 1RCBH model where cs\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$c_s$$\\end{document} is the speed of sound wave propagation.

Observation of Hydrostatic‐Pressure‐Modulated Giant Caloric Effect and Electronic Topological Transition

AbstractPhase transition is a fundamental phenomenon in condensed matter physics, in which states of matter transform to each other with various critical behaviors under different conditions. The magnetic martensitic transformation features significant multi‐caloric effects that benefit the solid‐state cooling or heat pumping. Meanwhile, the electronic topological transition (ETT) driven by pressure has been rarely reported in martensitic systems. Here, the modulation effects of hydrostatic pressure on phase transitions in a magnetic martensitic alloy are reported. Owing to the huge volume expansion during the transition, the martensitic transition temperature is driven from 339 to 273 K by pressure within 1 GPa, resulting in highly tunable giant baro‐ and magneto‐caloric effects (BCE and MCE) in a wide working temperature range. Interestingly, an ETT is further induced by pressure in the martensite phase, with a sudden drop of the measured saturation magnetization around 0.6 GPa. First‐principles calculations reveal a sharp change in the density of states (DOS) due to the orbit shift around the Fermi level at the same pressure and reproduce the experimental observation of magnetization. Besides, the ETT is accompanied by remarkable changes in the lattice parameters and the unit‐cell orthorhombicity. The study provides insight into pressure‐modulated exotic phase‐transition phenomena in magnetic martensitic systems.

A New Concept for Interpretation of the Viscoelastic Behavior of Aqueous Sodium Carboxymethyl Cellulose Systems.

Viscoelastic behaviors of aqueous systems of commercially available sodium carboxymethyl cellulose (NaCMC) samples with the degrees of substitution (DS) of approximately 0.68 and 1.3, and the weight-average molar masses (Mw) higher than 200 kg mol-1 dissolved in pure water and aqueous sodium chloride solutions were investigated over a wide concentration (c) range of NaCMC samples. The dependencies of the specific viscosity (ηsp), the average relaxation time (τw), and the reciprocal of the steady-state compliance (Je-1) on c were discussed. The relationships ηsp ∝ c3, τw ∝ c2, and Je-1 ∝ c, characteristic of the rod particle suspensions, were clearly observed in a range lower than the c where the critical gel behavior was observed. Thus, a new concept based on the rheology of rod particle suspensions was employed to interpret the viscoelastic behaviors obtained in the c range. In this context, NaCMC polymer molecules are assumed to behave as extended rod particles with length (L) and diameter (d), including effective electrostatic repulsive distances, due to the dissociation of Na+ in aqueous systems. Thus, the number density of polymer molecules is given to be ν = c/Mw, and viscoelastic parameters such as ηsp, τw, and Je-1 are calculated using the theoretical model for rod particle suspensions proposed by Doi and Edwards. This concept reasonably described not only the viscoelastic data obtained in this study but also those from other groups using NaCMC samples with different DS and Mw values.

Phase Transition Heat Transfer Enhancement of a Graphene-Coated Microporous Copper Surface Using Two-Step Electrodeposition Method

Abstract Owing to their exceptionally high thermal conductivity, there is a growing demand for graphene nanoparticles in phase transition heat transfer applications. This research delves into the exploration of various critical phenomena within the realm of surface science, specifically focusing on interactions at solid-liquid and liquid-liquid interfaces. In this work, graphene nanoparticles at varying concentrations are subject to electrochemical deposition on a microporous copper substrate to form graphene coated over microporous copper (GCOMC). The study encompasses a comprehensive analysis of surface characteristics, such as porosity, roughness, and wettability. Furthermore, the study involves the calculation of two key heat transfer metrics, the critical heat flux (CHF) and the boiling heat transfer coefficient (BHTC), through the execution of pool boiling experiments. The findings of this research underscore the remarkable superiority of GCOMC surfaces over their uncoated copper counterparts in terms of boiling performance. Particularly, the GCOMC surface showcases an impressive 87.5% enhancement in CHF and a 233% increase in BHTC compared to the bare copper surface. Furthermore, this investigation delves into a detailed quantitative analysis of bubble behavior, encompassing parameters such as bubble departure diameter, bubble departure frequency, and nucleation site density, employing high-speed camera techniques to comprehensively understand the underlying processes.