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This article studies the state and disturbance simultaneous estimation problem for a class of nonlinear descriptor systems with δQC$$ \delta \mathrm{QC} $$ using a dynamic event‐triggered mechanism. δQC$$ \delta \mathrm{QC} $$ refers to incremental quadratic constraints, which can provide a unified description of many types of common nonlinear functions. To reduce the negative impact of measurement outliers on the identification estimation, a stubborn state and disturbance observer co‐design scheme is proposed for the first time by embedding dynamic saturation output estimation errors. Meanwhile, a dynamic event‐triggered mechanism is introduced to avoid the need for continuously available output information, which can reduce the pressure on communication resources. By constructing a Lyapunov function, existence conditions of the stubborn state and disturbance observer are obtained in the form of a convex optimization problem so that the error estimation maintains an acceptable estimation performance. Finally, simulation examples illustrate the universality and stubbornness of the proposed observer. [ABSTRACT FROM AUTHOR]

This study focuses on addressing the challenge of adaptive finite‐time control for nonstrict‐feedback nonlinear systems subject to input delay and saturation. Neural networks (NNs) are utilized to handle unknown nonlinear functions, and Padé approximation is employed to effectively manage input delay. To mitigate the issue of "explosion of complexity," the command filter method is applied. By leveraging command filter technology and backstepping technique, an adaptive finite‐time control scheme is developed using NN approximation. The proposed control scheme demonstrates that the closed‐loop signals achieve semi‐global practical finite‐time stable (SGPFS), ensuring that the tracking error converges within a finite time to a small region around the origin. The effectiveness of the proposed scheme is validated through two simulation examples. [ABSTRACT FROM AUTHOR]

The proportional‐integral‐derivative (PID) was developed and recognized for its reliability. A PID controller is not only simple but also relatively cheap. However, the controller causes system performance degeneration over time due to the presence of windup in a motor speed control system. The windup phenomenon is caused by the saturated control state. Various anti‐windup methods were introduced to decrease a system's long settling time and extreme overshooting. Most anti‐windup techniques require integral switching between saturated and unsaturated states, whereby both versions of steady‐state integral proportional‐integral controller do not need integral switching mechanism. They possess a certain degree of decoupling between kp$$ {k}_p $$ and ki$$ {k}_i $$ tuning parameters and tested to allow a more comprehensive range of tuning in the absence of derivative control. This research investigated the impact of derivative control component on the tuning gain decoupling through hardware simulation. By integrating the derivative component, kd$$ {k}_d $$, the control system demonstrated an improved system stability and reduced overshoot. Result shows that the decoupling feature allows SIPIC01+D and SIPIC02+D controllers to produce performance with zero overshoot and short settling time. However, SIPIC01+D has better dynamical performance with fastest rise and settling time with no overshoot as compared to other anti‐windup controllers. [ABSTRACT FROM AUTHOR]

Flower colour is an important mediator of plant–pollinator interactions. While the reflectance of light from the flower surface and background are governed by physical properties, the perceptual interpretation of such information is generated by complex multilayered visual processing. Should quantitative modelling of flower signals strive for repeatable consistency enabled by parameter simplification, or should modelling reflect the dynamic way in which bees are known to process signals? We discuss why colour is an interpretation of spectral information by the brain of an animal. Different species, or individuals within a species, may respond differently to colour signals depending on sensory apparatus and/or individual experience. Humans and bees have different spectral ranges, but colour theory is strongly rooted in human colour perception and many principles of colour vision appear to be common. We discuss bee colour perception based on physiological, neuroanatomical and behavioural evidence to provide a pathway for modelling flower colours. We examine whether flower petals and floral guides as viewed against spectrally different backgrounds should be considered as a simple colour contrast problem or require a more dynamic consideration of how bees make perceptual decisions. We discuss that plants such as deceptive orchids may present signals to exploit bee perception, whilst many plants do provide honest signalling where perceived saturation indicates the probability of collecting nutritional rewards towards the centre of a flower that then facilitates effective pollination. [ABSTRACT FROM AUTHOR]

There has been general agreement that grain refinement upon severe plastic deformation (SPD) saturates at equivalent strains of 10–20, as a dynamic equilibrium between refinement and coarsening is established. Meanwhile, few reports question such steady state, but suggest another strain hardening regime might be entered for strains >1000. So far, neither an in‐depth analysis nor a general theory for such ultra‐SPD strain hardening has been established. The present work provides clear evidence for additional strain hardening at ultra‐severe strains. Although at this stage the strain hardening rate is awfully weak (≈0.03 MPa), it manifests in noticeable grain refinement and hardness increase. Texture and the existence of subgrains still support dislocation‐based plasticity. Specimens deformed to ultra‐severe strains possess improved thermal stability. Although an unambiguous conclusion regarding the origin of the ultra‐SPD strain hardening is currently not possible, the potential mechanisms are being discussed. While continuous impurity uptake from the anvils could explain the hardening and improved thermal stability, estimation of grain boundary migration rates suggests that a slight but continuous net refinement is also plausible. Together with structural transformations of grain boundaries, this offers an alternative, intrinsic source for ultra‐SPD hardening. It is hoped that this thought‐provoking conclusion stimulates further research into this subject. [ABSTRACT FROM AUTHOR]

It has been shown using proton magnetic resonance spectroscopy (1H MRS) that, in a group of females, whole‐body insulin resistance was more closely related to accumulation of saturated intramyocellular lipid (IMCL) than to IMCL concentration alone. This has not been investigated in males. We investigated whether age‐ and body mass index‐matched healthy males differ from the previously reported females in IMCL composition (measured as CH2:CH3) and IMCL concentration (measured as CH3), and in their associations with insulin resistance. We ask whether saturated IMCL accumulation is more strongly associated with insulin resistance than other ectopic and adipose tissue lipid pools and remains a significant predictor when these other pools are taken into account. In this group of males, who had similar overall insulin sensitivity to the females, IMCL was similar between sexes. The males demonstrated similar and even stronger associations of IMCL with insulin resistance, supporting the idea that a marker reflecting the accumulation of saturated IMCL is more strongly associated with whole‐body insulin resistance than IMCL concentration alone. However, this marker ceased to be a significant predictor of whole‐body insulin resistance after consideration of other lipid pools, which implies that this measure carries no more information in practice than the other predictors we found, such as intrahepatic lipid and visceral adipose tissue. As the marker of saturated IMCL accumulation appears to be related to these two predictors and has a much smaller dynamic range, this finding does not rule out a role for it in the pathogenesis of insulin resistance. [ABSTRACT FROM AUTHOR]

Experiments on visually grounded, definite reference production often manipulate simple visual scenes in the form of grids filled with objects, for example, to test how speakers are affected by the number of objects that are visible. Regarding the latter, it was found that speech onset times increase along with domain size, at least when speakers refer to nonsalient target objects that do not pop out of the visual domain. This finding suggests that even in the case of many distractors, speakers perform object‐by‐object scans of the visual scene. The current study investigates whether this systematic processing strategy can be explained by the simplified nature of the scenes that were used, and if different strategies can be identified for photo‐realistic visual scenes. In doing so, we conducted a preregistered experiment that manipulated domain size and saturation; replicated the measures of speech onset times; and recorded eye movements to measure speakers' viewing strategies more directly. Using controlled photo‐realistic scenes, we find (1) that speech onset times increase linearly as more distractors are present; (2) that larger domains elicit relatively fewer fixation switches back and forth between the target and its distractors, mainly before speech onset; and (3) that speakers fixate the target relatively less often in larger domains, mainly after speech onset. We conclude that careful object‐by‐object scans remain the dominant strategy in our photo‐realistic scenes, to a limited extent combined with low‐level saliency mechanisms. A relevant direction for future research would be to employ less controlled photo‐realistic stimuli that do allow for interpretation based on context. [ABSTRACT FROM AUTHOR]

For field development and drilling decisions, production assets and reservoir engineers require dynamic reservoir properties, such as saturation and pressure changes of a reservoir from the pre‐production virgin state. To date, geophysicists have produced time‐lapse (4D) seismic attributes (mostly on stacked seismic data) rather than dynamic parameters directly. In this paper, we present a new method to estimate saturation and pressure properties from time‐lapse seismic data to provide to reservoir engineers. This new three‐step method is demonstrated over the Edvard Grieg field in the North Sea. We can realize this method thanks to advanced seismic multi‐component acquisition via PP and PS seismic data and processing that allows accurate estimation of amplitude‐variation‐with‐offset parameters P‐ and S‐impedances. With time‐lapse P‐ and S‐impedances optimally resolved, we estimate a stable set of axes identifying water saturation increase (water replacing oil), gas saturation increase (gas injection or gas out of solution), pressure increase (at injectors) and pressure decrease (at producers). Once these axes are obtained, we convert every 4D P‐ and S‐impedance data points into 4D pseudo‐saturation and pseudo‐pressure using a transformation of coordinates. We next use the rock physics relationships of this field to show that a linear relationship can be used to map any 4D change in the field from impedances to saturations and pressures. Key locations in the field with largest saturation and pressure changes are used to find calibration values at these extreme points. Next, from the pseudo‐seismic 4D data, a linear mapping is used to calculate actual reservoir property changes (fractions for saturation and bars for pressure). This allows us to obtain fieldwide dynamic values for water and gas saturations and injection and production related pressure changes. The results are shown, and dynamic changes are interpreted on the Edvard Grieg field data. [ABSTRACT FROM AUTHOR]

Trickle bed reactors (TBR) are widely used in the chemical industries. These reactors involve gas and liquid flow through a catalyst‐packed bed. For optimal TBR performance, it is crucial to achieve a uniform distribution of gas and liquid among the catalyst particles. However, in multitubular reactors with slender tubes, flow maldistribution near the tube walls is a common issue. Therefore, a comprehensive understanding of local phase and flow distribution is essential for designing and operating reactors with slender tubes. This article employs Magnetic Resonance Imaging (MRI) to characterize the three‐dimensional distribution of the two‐phase trickle flow within a slender tube. Three quantities are characterized: gas‐liquid‐solid distribution, particle wetting efficiency, and the flow field. Structure and flow MRI images are processed to calculate these quantities. Additionally, a novel postprocessing technique is introduced to determine the liquid distribution over individual particle surfaces. This distribution is determined at several axial and radial positions. [ABSTRACT FROM AUTHOR]

This article addresses the event‐triggered adaptive consensus control of nonlinear multi‐agent systems with unknown control direction and actuator saturation. A new robust adaptive control algorithm based on an event‐triggered mechanism is designed. The smooth Lipschitz function approximates the saturated nonlinear function, while the Nussbaum function handles unknown control directions and residual terms. The event‐triggered mechanism is designed to determine the time of communication, significantly reducing the communication burden. An additional estimator is utilized to deal with unknown parameters involved in neighbor dynamics and prevent information exchange to consistency errors between connected subsystems. The results show that all the signals of the closed‐loop system are uniformly bounded, and the consensus tracking error converges to a bounded set. Meanwhile, Zeno's behavior is eliminated. Simulation results confirm the superiority of the proposed method. [ABSTRACT FROM AUTHOR]

The complex lithology, frequent interbedding and strong heterogeneity of the shale oil reservoir in Lucaogou Formation of the Middle Permian in Jimsar Sag lead to the complexity of litho‐electric parameters and the low accuracy of conventional reservoir saturation evaluation methods. Therefore, in this paper, automatic lithologic identification was firstly performed with the optimization inversion method of mineral components and K‐means clustering algorithm, and then, litho‐electric experiments were carried out to determine the litho‐electric parameters of different lithologies. Furthermore, the shale oil reservoir saturation calculation models of different lithologies were optimized and determined. Then, a composite water saturation model (Composite‐SW) based on complex lithology identification was constructed. Finally, the model was verified and analysed with the experimental results of water saturation. The coefficient of correlation between the calculation results of the Composite‐SW model and the core experiment results reached.88, indicating that the model was much better than conventional models. The model can be widely applied in logging evaluation of the continental mixed shale oil reservoir in the study area. The study provides a new idea for oil saturation evaluation of continental shale oil reservoirs and is significant for evaluating other types of shale oil reservoirs. [ABSTRACT FROM AUTHOR]

Background: Despite the high number of synthetic androgenic–anabolic steroids, testosterone is still misused for doping in amateur and professional sports. However, only few studies investigated the dose–response effects of testosterone beyond its physiological concentrations and in over 90 years of research, no saturation dosage has been experimentally described for exogenous testosterone administration. Objectives: We want to elucidate the physiological and pathophysiological effects of supra‐physiological testosterone application and close this gap in testosterone dose–response data. Materials and methods: Male orchiectomized rats were treated with different testosterone doses ranging from 0.1 to 50 mg/kg body weight for 3 weeks. Several physiological endpoints (e.g., body weight, organ and muscle weight, muscle strength, muscle fiber size) were examined during and after the termination of the treatment with an adjusted Hershberger assay, open‐field‐test, and (immuno‐)histologic. Results: The wet weights of androgen responsive organs (penis, prostate, seminal vesicle) showed a significant increase in a dose‐dependent manner. Histological evaluation of the prostate showed a significant higher percentage of KI67 positive prostate nuclei in the highest dosage group and an increasing hyperplasia with increasing testosterone administered. A significant anabolic effect was only observed in Levator ani wet weight, and to minor degree for the cardiac muscle. Regarding other skeletal muscles (Musculus soleus and Musculus gastrognemicus), no significant testosterone effects were observed. We showed a significant increasing dosage–response effect for testosterone in androgen responsive organs with saturation at the two highest concentration of 10 and 50 mg/kg body weight. Discussion and conclusion: The dose‐dependent androgenic effects of testosterone were well observable and the anabolic effects on muscle tissue were visible although to a lesser degree, without the support of aerobic exercise and a protein rich diet. Future studies should investigate a combinatorial effect of testosterone and training. Nevertheless, with the chosen range of applied testosterone, we showed a saturation of testosterone effects in prostate, seminal vesicle, penis, and Levator ani. [ABSTRACT FROM AUTHOR]

Geometric heterogeneities in tight reservoir rocks saturated with a fluid mixture may exhibit different scale distribution characteristics. Conventional models of rock physics based on poroelasticity, which usually consider single‐scale pore structure and fluid patches, are inadequate for describing elastic wave responses. A major challenge is to establish the relationship between the wave response at different spatial scales and frequencies. To address this problem, three sets of observational data over a wide frequency range were obtained from a tight oil reservoir in the Ordos Basin, China. Ultrasonic measurements were made on eight sandstone samples at partial oil‐water saturation at 0.55 MHz. Data from six borehole measurements and seismic profiles were acquired and analyzed at about 10 kHz and 30 Hz, respectively. Analysis of the cast thin sections shows that dissolution pores and microcracks generally develop, with fractal dimensions of the pores ranging from 2.45 to 2.67 for the samples with porosities between 5.1% and 10.2%. Compressional wave velocity and attenuation were estimated from the observed data. The results show that the velocity dispersion from seismic to ultrasonic frequencies is 10.02%, mostly occurring between sonic and ultrasonic frequencies. The attenuation is stronger at higher oil saturation. The relationships between velocity, attenuation, and wavelength were established and can be used for further forward modeling and seismic interpretation studies. A partial saturation model has been derived based on effective differential medium theory and a double double‐porosity model, assuming that the medium contains fractal cracks and fluid patches. The effects of scale and saturation on wave responses are prevalent. Modeling results consistent with observed data show that the radii of cracks and fluid patches range from 0.1 μm to 2.8 mm, affecting ultrasonic, acoustic, and seismic attenuation. The multiscale data and proposed model quantify the relationship between fracture and fluid distributions and attenuation and could be useful for upscaling to the reservoir scale. The study helps improve the understanding of seismic wave propagation in partially saturated rocks, which has potential applications in seismic exploration, hydrocarbon production in reservoirs, and CO2 sequestration in aquifers. Plain Language Summary: The physical properties of the rock and fluid can be inferred from the measured elastic wave responses and energy dissipation characteristics. However, the effects of heterogeneities of different sizes and at different frequencies can hinder studies to quantify wave responses in a partially saturated porous medium, which are usually based on laboratory measurements. A major problem is the difference between observed frequencies and scales: megahertz in the laboratory, 10 of kilohertz in the borehole scale, and hertz in the seismic exploration scale. In this work, the frequency‐ and saturation‐dependent compressional velocity and attenuation are investigated using three geophysical data sets from the same tight reservoirs. A strong velocity dispersion over the measured frequency range is observed. The stronger attenuation at partial saturation may be caused by the multiscale heterogeneities of the pore structure and fluid patch distribution. A fractal poroelasticity model is developed by gradually inserting inclusions of different sizes with compliant pores and liquid patches into a homogeneous host skeleton. The wave responses are significantly affected by scale distribution and saturation. The proposed model, verified by the measured data, can be useful in interpreting the anelasticity of tight heterogeneous reservoirs in a broadband range. Key Points: We investigate how fluid saturation affects wave attenuation and dispersion over a wide frequency range in tight sandstone layersA partial saturation model describes the fractal properties of the layersThe size of the cracks and fluid patches are determined by applying the fractal model to the multiscale data [ABSTRACT FROM AUTHOR]

We investigate the dynamical behavior of deterministic and stochastic waterborne pathogen models with saturated incidence rates. In particular, the indirect transmission via person–water–person contact is half‐saturated and the direct transmission by person–person contact takes the saturated form. Possible equilibrium points of the model are investigated, and their stability criterion is discussed. Basic reproduction number R0$$ {\mathcal{R}}_0 $$ of the model is obtained through the next‐generation matrix method. It has been shown that the disease‐free equilibrium is locally stable when R0<1$$ {\mathcal{R}}_0<1 $$ and unstable for R0>1$$ {\mathcal{R}}_0>1 $$. Furthermore, a stochastic Lyapunov method is adopted to establish sufficient conditions for the existence and uniqueness of an ergodic stationary distribution of the proposed stochastic model, which reveals that the infection will persist if R0s>1$$ {\mathcal{R}}_0^s>1 $$. We also obtain an exact expression of the probability density function near the quasi‐endemic equilibrium of stochastic system. Finally, numerical simulations are carried out to support our analytical findings. Results suggest that saturation constants in both direct and indirect transmissions play a positive role in controlling disease. Our results may provide some new insights for the elimination of waterborne disease. [ABSTRACT FROM AUTHOR]

Understanding community saturation is fundamental to ecological theory. While investigations of the diversity of evolutionary stable states (ESSs) are widespread, the diversity of communities that have yet to reach an evolutionary endpoint is poorly understood. We use Lotka–Volterra dynamics and trait‐based competition to compare the diversity of randomly assembled communities to the diversity of the ESS. We show that, with a large enough founding diversity (whether assembled at once or through sequential invasions), the number of long‐time surviving species exceeds that of the ESS. However, the excessive founding diversity required to assemble a saturated community increases rapidly with the dimension of phenotype space. Additionally, traits present in communities resulting from random assembly are more clustered in phenotype space compared to random, although still markedly less ordered than the ESS. By combining theories of random assembly and ESSs we bring a new viewpoint to both the saturation and random assembly literature. [ABSTRACT FROM AUTHOR]

Invasive plants are a prominent threat to ecosystems and economies worldwide. Knowing the identity of invasive plants is critical for preventing their introduction and spread. Yet several lines of evidence, including spatial and taxonomic biases in reporting and the ongoing emergence of new invasives, suggest that we are missing basic information about the identity of invasive plants. Using a database of invasive plants reported in the peer‐reviewed literature between 1959 and 2020, we examined trends in the accumulation of new invasive plants over time and estimated the size of the current pool of invasive plants both continentally and globally. The number of new invasive plants continues to increase exponentially over time, showing no sign of saturation, even in the best studied regions. Moreover, a sample‐size based rarefaction‐extrapolation curve of reported taxa suggests that what is documented in the current literature (3008 taxa) only captures 64% of the likely number of invasive plants globally (4721 taxa ± 132 SE). These estimates varied continentally; less than half of invasive plant taxa have likely been identified in Oceania and Central and South Americas. Studies that included multiple invasive plants (e.g., floristic studies) were much more efficient at adding new taxa to our global understanding of what is invasive (identifying 4.2 times more new taxa than single‐taxon studies). With more potential invaders arriving every day, this analysis highlights a critical gap in our knowledge of the current invasive plant pool. Expanding invasion science to better encompass understudied geographic areas and increasing the numbers of floristic surveys would greatly improve our ability to accurately and efficiently identify what taxa are invasive. Preventing invasive plant introductions is incumbent upon knowing the identity of invasive plants. Thus, large knowledge gaps remain in invasion ecology that hinder efforts to proactively prevent and manage invasive plants. [ABSTRACT FROM AUTHOR]

Objectives: Ventilation using 100% oxygenation creates a risk of fire during laser microlaryngeal surgery (MLS). The purpose of this study is to describe the technique of transnasal high‐flow ventilation using laser safe (30%) oxygen conditions, measure the intraoperative real‐time laryngeal oxygen concentration, and examine patient saturation status using this technique. Methods: Prospective IRB approved study of patients undergoing tubeless laser MLS using high‐flow nasal oxygenation. Delivered oxygen concentration was reduced from 100% to 30% before lasering using an oxygen‐air blender then increased to 100% post‐laser procedure. Outcome measures included time for laryngeal oxygen concentration to equalize to laser safe levels; time to, methods of and duration of rescue ventilation; and desaturation rates and apnoeic times at both 100% and 30% oxygen deliveries. Results: Fifty patients were recruited (mean age = 47.4 years). Mean laryngeal oxygen concentration (%) at 100% and 30% deliveries was 98.46 and 31.45, respectively. Mean (SD) of laryngeal oxygen concentration equalization time to 30% (seconds) was 9.4 (3.69). At 30% oxygen delivery desaturation rate was faster and apneic time shorter compared with 100%. Eighteen patients required rescue (jet) ventilation and they had a faster apneic desaturation rate (%/minute) than patients not requiring rescue. Mean (SD) apneic time (minutes) at 30% delivery was 4.56 (2.25) and 4.41 (2.18) in rescue versus non‐rescue groups respectively. BMI was the only significant predictor of desaturation rate at 30% oxygen delivery. Conclusion: It is possible to achieve a safe time window for use of laser during MLS using transnasal humidified high‐flow ventilation by delivering 30% oxygen concentration. Level of Evidence: 4 Laryngoscope, 133:634–639, 2023 [ABSTRACT FROM AUTHOR]

The dual‐excited synchronous condenser (DESC) has two field windings whose axes are located at direct and quadrature axes respectively. The DESC has more capacity of absorbing reactive power than that of the traditional synchronous condenser (TSC). However, the q‐axis field winding distributed on the d‐axis magnetic pole surface can decrease the magnetic circuit area of the rotor core of DESC, thus it may result in the increase of the total harmonic distortion (THD) of the magnetic field and the oversaturation of the rotor magnetic circuit. In order to obtain better electromagnetic characteristics of DESC, a q‐axis field winding structure is proposed by optimising the number of slots, slot pitch and slot dimensions. The influences of the number and pitch of slot in q‐axis on the air‐gap radial flux density and THD of DESC are studied under the d‐, q‐ and dual‐axis excitation modes. The dimensions of the q‐axis slots are optimised by combining the time‐stepping finite element method and Taguchi method, and the optimal structure of q‐axis field winding is obtained. A 10‐kVar DESC is developed to verify the simulation results. This study provides theoretical basis for the design and manufacture of the DESC. [ABSTRACT FROM AUTHOR]

On Mars, condensation is the major factor constraining the vertical distribution of water vapor. Recent measurements of water and temperature profiles showed that water can be strongly supersaturated at and above the level where clouds form during the aphelion and perihelion seasons. Since 2018, the near‐infrared spectrometer (NIR) of the Atmospheric Chemistry Suite onboard the Trace Gas Orbiter has measured H2O and temperature profiles using solar occultation in the infrared from below 10 to 100 km of altitude. Here, we provide the first long‐term monitoring of the water saturation state. The survey spans 2 Martian years from Ls = 163° of MY34 to Ls = 170° of MY36. We found that water is often supersaturated above aerosol layers. In the aphelion season, the water mixing ratio above 40 km in the mid‐to‐high latitudes was below 3 ppmv and yet is found to be supersaturated. Around the perihelion, water is also supersaturated above 60 km with a mixing ratio of 30–50 ppmv. Stronger saturation is observed during the dusty season in MY35 compared to what was observed in MY34 during the Global Dust Storm and around the perihelion. Saturation varied between the evening and morning terminators in response to temperature modulation imparted by thermal tides. Although water vapor is more abundant in the evening, colder morning temperatures induce a daily peak of saturation. This data set establishes a new paradigm for water vapor on Mars, revealing that supersaturation is nearly ubiquitous, particularly during the dust season, thereby promoting water escape on an annual average. Plain Language Summary: The rate of water loss from Mars depends on hydrogen, the main product of the H2O photodissociation escaping from the upper atmosphere. The ability of water to reach high altitudes and to be a direct source of atomic hydrogen is limited by cloud formation, which holds water vapor in the lower atmosphere. This process is regulated by temperature and pressure. Condensation starts when the temperature is cold enough and condensation nuclei (CN) (e.g., small dust particles) are available. If CN are lacking, or their sizes are too small, or the temperature drops too fast, then water vapor becomes supersaturated. Recent studies have shown that Martian water vapor is often supersaturated. Here, we present the first seasonal cycle of the saturation state from simultaneous measurements of water and temperature during two Martian years by Atmospheric Chemistry Suite on the Trace Gas Orbiter. Our results show that supersaturation is typical on Mars. It occurs above clouds both in the aphelion and perihelion seasons as well as in the lower polar atmosphere. We demonstrate supersaturation to be an important factor facilitating the escape of water. Unlike the Earth, water easily penetrates the upper atmosphere and reaches photodissociation altitudes. Key Points: Long‐term observations of H2O saturation state in the atmosphere of Mars show that supersaturation is nearly ubiquitous above aerosol layersDuring the dusty season, the supersaturation is stronger in MY35 compared to MY34More water was found in the evening terminator and stronger supersaturation in the morning terminator [ABSTRACT FROM AUTHOR]

This paper presents new convex conditions to design robust and linear parameter varying (LPV) gains for continuous time‐varying systems subject to saturating actuator and energy bounded disturbances. The input‐to‐state stability conditions are used to design controllers ensuring the minimization of the L2‐gain between the disturbance input and the controlled output. Furthermore, optimization procedures to maximize the estimate of the region of attraction, and the bound to the control signal as well, are formulated. The efficacy of the proposed methods is illustrated with numerical examples, including a reference tracking problem, where realistic simulations are performed. [ABSTRACT FROM AUTHOR]

Proportional‐integral (PI) controller is still a widely used closed‐loop controller in industrial applications due to its simplicity. PI controllers experience difficulty in having both non‐overshoot with short rise time. Such unfavorable response is due to its coupled tuning‐gains and the integral windup, which eventually leads to system instability. Various anti‐windup techniques have been proposed. However, similar to the conventional PI controllers, most of these techniques have coupled proportional and integral tuning gains that affect one another. The controllers contain adaptive switching between the conventional and its designated integral control depending on the saturation state. This paper proposes a robust non‐switching anti‐windup PI controller with semi‐decoupling tuning gain. Speed control simulation and experimental testing are conducted to investigate the impact of the various tuning gain dependency. The proposed controller shows a fast response with no overshoot as compared to the conventional and other non‐switching anti‐windup PI controllers with coupling and decoupling tuning gain at certain loading conditions. [ABSTRACT FROM AUTHOR]

Several models of classical aeolian sand transport mechanism have been developed to predict the rate of sand transport. However, the values predicted through modeling almost always display large and significant differences from the measured values. The reason for such discrepancies is not fully understood. By studying the effects of wind velocities and fetch lengths on the C values in the model proposed by Lettau and Lettau in 1978, we found that the saturation level of the measured sand flow can significantly affect the accuracy of the predicted value. To solve this problem, we introduced an index (δ) to represent the saturation level. The closer the δ value is to 1, the greater the chance that the sand flow is saturated. This new approach only requires measurement of the saturated sand flow data to verify the robustness of the aeolian sand transport model, a step that has been neglected by previous researchers. Our results suggest that the value of C = 6.7 proposed in the Lettau and Lettau model is sound and reliable if the sand flow is saturated. We proposed the conditions required for the sand flow to reach saturation and generated an equation to predict the sand transport saturation length (Lsat). Accordingly, we estimated Lsat to be approximately 92 m when u* = 0.47 m s−1 for the studied sand surface, which is also the minimum wind shear velocity at which the sand flow can potentially reach saturation. [ABSTRACT FROM AUTHOR]

In this article, the H∞ state estimation problem is investigated for a class of distributed parameter systems (DPSs). In order to estimate the state of DPSs, we give a partition of spatial interval with a finite sequence and, on each subinterval, one sensor is placed to receive the measurements from the DPS. Due to the unexpected environment changes, the measurements will probably contain some outliers. To eliminate the effects of the possibly occurring outliers, we construct a stubborn state estimator where the innovation is constrained by a saturation function. By using Lyapunov functional, Wirtinger inequality and piecewise integration, some sufficient conditions are obtained under which the resulting estimation error system is exponentially stable and the H∞ performance requirement is satisfied. According to the obtained analysis results, the desired H∞ state estimator is designed in terms of the solution to a set of matrix inequalities. Finally, a numerical simulation example is given to verify the effectiveness of the proposed state estimation scheme. [ABSTRACT FROM AUTHOR]

Summary: Switch‐mode power supplies (SMPSs) are widely exploited to interface electrical energy sources to motors and other electrical loads. Inductors are usually the biggest and heaviest components in SMPSs, limiting their overall power density. Therefore, there is an increasing interest in designing SMPSs with partially saturating inductors, because this significantly reduces their weight and size, thus increasing power density. This paper provides a review of nonlinear behavioral models (based on easy‐to‐measure quantities) of the inductance, power loss, and temperature rise of inductors working, at least partially, in magnetic saturation. This survey discusses the pros, cons, and ranges of validity of these models, with a glimpse at their application to SMPS simulation, design, monitoring, and control. [ABSTRACT FROM AUTHOR]

Aims: To assess the outcomes of an early oxygen saturation screening programme in apparently healthy newborns for the detection of cardiac and non‐cardiac disease. To describe the aetiology and incidence of infants with oxygen saturations <95% in the first 6 h of life and describe the management to discharge. In addition, we sought to identify any risk factors for failed early saturations. Methods: This is a retrospective hospital cohort assessing outcomes of an early saturation screening programme performed in apparently healthy newborns. Infants with oxygen saturations less than 95% were identified and their clinical notes were hand‐searched. Descriptive statistics were used to present demographics, proportion of infants who passed or failed screening, subsequent diagnoses and short‐term outcome. Multivariate logistic regression was used to identify independent associations of clinical factors (birthweight, gestation, elective caesarean section and gender) with failed screening. Results: Between 2014 and 2019, 14 956 healthy newborns were assessed within the first 6 h, 94 (0.63%) failed the early saturation screen. The most common causes for saturation <95% were respiratory disease or delayed transition. There were 31 (33%) infants admitted to the NICU with an additional baby requiring emergency transfer to a cardiac centre. Infants were 28 times more likely to have saturations <95% if born by elective caesarean section (odds ratio 28, conflict of interest (18.54–42.82)). Conclusion: In apparently healthy newborns, early assessment of oxygen saturation, combined with clinical assessment and subsequent intervention can identify important conditions and should be considered as standard care. [ABSTRACT FROM AUTHOR]

This article proposes a distributed model‐free adaptive consensus tracking control (DMFACTC) approach for a class of unknown heterogeneous nonlinear discrete‐time multi‐agent systems (MASs) with sensor saturation and measurement disturbance to perform consensus tracking tasks. Meanwhile, both fixed and switching topologies are considered, where only a subset of agents can acquire the desired trajectory information in each topology. A time‐varying linear data model for each agent is first established by utilizing the dynamic linearization method to formulate this algorithm. Merely, the input data and the saturated output data with measurement disturbance of each agent are applied to construct the DMFACTC algorithm without employing any dynamics model information of MASs. The convergence of the designed scheme is strictly proved. It illustrates that the output saturation and switching topologies do not affect the stability of MASs. Moreover, even if the sensor saturation, measurement disturbance, and switching topologies happen simultaneously, the DMFACTC also guarantees that the tracking errors of MASs converge to a small range around the origin. Furthermore, two numerical simulations and a realistic filling system simulation further verify the correctness and effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

In practice the states of a system are not directly available that are difficult to measure by sensors. This article proposes an observer‐based controller for fractional‐order neutral‐type delay systems with actuator saturation. A feedback algorithm is constructed by applying the Lyapunov direct method. Moreover, based on the observer, the gains of controller and observer are determined by solving a set of nonlinear matrix inequalities. Therefore, an iterative algorithm including the convex optimization is also proposed to solve the inequalities. An example is given to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

This article is concerned with the parameter estimation problem of a nonlinear output‐error system with saturation and dead‐zone nonlinearity. The saturation nonlinearities and the dead‐zone nonlinearities are widely encountered in engineering applications and the identification for the nonlinear systems with these nonlinearities is very crucial. Based on the over‐parameterization identification model and the auxiliary model identification idea, an auxiliary model least‐squares‐based iterative algorithm is presented for estimating the parameters of the nonlinear system with saturation and dead‐zone nonlinearity. In order to enhance the computational efficiency, an auxiliary model gradient‐based iterative algorithm is presented for the nonlinear system. Using the multi‐innovation identification theory, an auxiliary model multi‐innovation gradient‐based iterative algorithm is derived for tracking time‐varying parameters. An example is carried out to show the effectiveness of the proposed algorithms. The numerical simulation results show that all the proposed algorithms can generate accurate parameter estimates. [ABSTRACT FROM AUTHOR]

This study aims to investigate the influence of high‐intensity sunlight radiation on the photooxidation of tropical oils (TO). Coconut oil (CNO), palm oil (PO), and palm kernel oil (PKO) were chosen for determining the indicators of photooxidation when exposed to and in the absence of sunlight for 7 weeks. The results showed a significant (P < 0.05) increase in free fatty acid (FFA) levels and peroxide value (PV) when the TO were exposed to sunlight. The iodine value and color content decreased significantly (P < 0.05) due to the decomposition of unsaturated FFA owing to the breaking down of the π‐bonds and the degradation of color pigments during photooxidation. Fourier transform infrared spectroscopy (FTIR) analysis showed strong vibrational absorptions at 1721 and 3505 cm−3, 1720 and 3560 cm−3, and 1721 and 3554 cm−3 for the CNO, PO, and PKO samples exposed to sunlight, respectively. These bands can be attributed to the presence of secondary oxidation products, which were absent in the TO that were not exposed to sunlight. A simulation was performed to support the FTIR results, which also indicated peaks from the secondary oxidation products at 1744 and 3660 cm−3. The study also revealed that the rate of photooxidation was different for each TO. The rate of oxidation followed the order PO > PKO > CNO. In contrast, no notable changes were observed in the TO kept away from sunlight. These results suggest that exposing TO to sunlight influences their oxidation stability and quality. [ABSTRACT FROM AUTHOR]

Purpose: A new sequence combining chemical‐exchange saturation‐transfer (CEST) with traditional MRS is used to simultaneously determine metabolite content and effects of magnetization exchange. Methods: A CEST saturation block consisting of a train of RF‐pulses is placed before a metabolite‐cycled semi‐LASER single‐voxel spectroscopy sequence. The saturation parameters are adjustable to allow optimization of the saturation for a specific target. Data were collected in brain from 20 subjects in experiments with different B1‐settings (0.4‐2.0 µT) on a 3T MR scanner. CEST Z‐spectra were calculated from water intensities and fitted with a multi‐pool Lorentzian model. Interrelated metabolite spectra were fitted in fitting tool for arrays of interrelated datasets (FiTAID). Results: Evaluation of traditional Z‐spectra from water revealed exchange effects from amides, amines, and hydroxyls as well as an upfield nuclear Overhauser effect. The magnetization transfer effect was evaluated on metabolites and macromolecules for the whole spectral range and for the different B1 levels. A correction scheme for direct saturation on metabolites is proposed. Both magnetization‐transfer and direct saturation proved to differ for individual metabolites. Conclusion: Using non‐water‐suppressed spectroscopy offers time‐saving simultaneous recording of the traditional CEST Z‐spectrum from water and the metabolite spectrum under frequency‐selective saturation. In addition, exchange and magnetization‐transfer effects on metabolites and macromolecules can be detected, which might offer additional possibilities for quantification or give further insight into the composition of the traditional CEST Z‐spectrum. Apparent magnetization‐transfer effects on macromolecular signals in the 1H‐MR spectrum have been found. Detailed knowledge of magnetization‐transfer effects is also relevant for judging the influence of water‐suppression on the quantification of metabolite signals. [ABSTRACT FROM AUTHOR]

The photoluminescence (PL) saturation of CdSe/ZnS core/shell inorganic semiconductor quantum dots (QDs) and its utility as a probe for saturated excitation (SAX) microscopy are reported. Under saturating excitation power densities, the PL signal was demodulated and recorded at harmonics of the fundamental frequency. For commercially available Qdot® 655 ITK™ QDs, the power density required to achieve saturation was dependent upon the local environment of the QDs. For QDs deposited and dried on a glass substrate, the excitation power density required for PL saturation was less than 1 kW/cm2. Compared to this, saturation of PL for QDs dispersed in water required an excitation power density greater than 200 kW/cm2. This observation is manifested as a limitation in the imaging of hydrated samples, as demonstrated for HeLa cells labelled with biotinylated‐phalloidin followed by labelling with streptavidin‐coated QDs. As saturation affects the obtained spatial resolution in several imaging formats, including confocal imaging, the provided data will aid in obtaining the optimal spatial resolution when using QD probes to image biological samples. [ABSTRACT FROM AUTHOR]

In the ancient rock record, early replacement of metastable marine calcium carbonate deposits by dolomite has long been associated with evidence of arid depositional environments. Such associations led to the development of the seepage reflux dolomitization model, whereby magnesium‐rich marine waters concentrated by evaporation descend into underlying sediments, replacing primary aragonite and calcite deposits with dolomite through rock–water interaction. In the modern arid coastal systems of Qatar, where marine waters concentrate to halite saturation, both aqueous geochemical measurements and mineralogical investigations show that replacement of calcium carbonate deposits by dolomite is not occurring to any consequential degree. At best dolomite formation is minor and localized. Instead, modern and mid‐Holocene coastal deposits retain their original mineralogy, showing little evidence of carbonate precipitation reactions with the notable exception of beachrock formation. Pleistocene coastal deposits are mostly absent in comparison with both Qatar Holocene coastal deposits, and Pleistocene coastal deposits from more humid settings. The lack of onshore Pleistocene‐aged carbonate outcrops in Qatar, as well as regionally, is interpreted to reflect coastal sediment denudation during emergence due to: (i) the absence of coastal marine lithification; and (ii) the absence of meteoric cementation and root stabilization in the highly‐arid realm. In contrast, marine Palaeogene and Miocene carbonate deposits are preserved in outcrop in Qatar, having suffered marine lithification by dolomite, thus promoting retention of carbonate strata through subsequent lowstands. These older deposits formed during times of ocean acidification, which, based on natural system and laboratory investigations, is interpreted to promote metastable carbonate dissolution and dolomite formation. The highly‐arid Holocene and Pleistocene coastal systems of Qatar represent limestone factories, but these deposits are not being retained to the rock record. Based on these observations, the association between the occurrence of dolomite and arid depositional settings may be to some degree a preservation bias. [ABSTRACT FROM AUTHOR]

This article studies the H∞ fault estimation (FE) problem for linear discrete time‐variant systems with actuator and sensor saturations. To handle the saturation nonlinearities for FE problem, a pair of an auxiliary linear model and an associated performance function augmenting from the conventional H∞ performance index are constructed. Based on this pair, the original FE problem is readdressed as a two‐step optimization issue with an indefinite quadratic cost function. For a feasible optimization solution, the partial equivalence between a stationary point for a quadratic optimization problem and a projection for vectors in indefinite inner‐product space is utilized. A Krein‐space based inner product interpretation for the indefinite cost function is established and optimal linear estimation technique is employed to derive the stationary point of the aforementioned indefinite quadratic cost function. The existence condition of the fault estimator is explicitly obtained, and the fault is reconstructed analytically via a forward recursion algorithm. Two examples are given to show the effectiveness of the proposed FE scheme. [ABSTRACT FROM AUTHOR]

A multitude of models for soil organic carbon (SOC) dynamics are available to predict management impacts on SOC dynamics in its interaction with environmental factors. Most models include one SOC pool that has no or a very slow, negligible turnover. For this pool of long‐term stabilized (LTS) organic matter, we assumed a dynamic physical protection, whereby organic matter is protected in micropores and exposed to microbial access due to soil structure dynamics. Dynamics of the LTS pool is of special interest because of its very long turnover time. Therefore, it is of special importance whether the size of this pool is unlimited or if it reaches a saturation state. We investigated this topic by applying the CCB (CANDY Carbon Balance) model on a dataset from a long‐term experiment that started in 1983 in Bad Lauchstädt, Germany on a Haplic Chernozem and includes bare fallow treatments with the application of farmyard manure at different rates from 5 to 20 kg m−2 year−1. Observations of SOC development over time supported our hypothesis about the existence of a saturation effect and were used to calibrate the CCB model with the hypothetical assumption of a limited LTS pool size. The model results suggest an upper limit of the LTS pool of 1.07 M% (percent of dry soil mass) SOC for the Bad Lauchstädt site. Furthermore, model calibration of LTS turnover revealed that organic matter in this pool is released from its protected state at a very low rate of 0.003 year−1. Highlights: Long‐term bare fallow field experiment with FYM input rates up to 20 kg m−2Predicted long‐term SOC dynamics reflect observationsProof of non‐linear relationship between SOC storage and carbon input rateEvidence for limited protection capacity for SOC (saturation effect) [ABSTRACT FROM AUTHOR]

Purpose: To develop and validate a saturation‐delay‐inversion recovery preparation, slice tracking and multi‐slice based sequence for measuring whole‐heart native T1. Method: The proposed free‐breathing sequence performs T1 mapping of multiple left‐ventricular slices by slice‐interleaved acquisition to collect 10 electrocardiogram‐triggered single‐shot slice‐selective images for each slice. A saturation‐delay‐inversion recovery pulse is used for T1 preparation. Prospective slice tracking by the diaphragm navigator and retrospective registration are used to reduce through‐plane and in‐plane motion, respectively. The proposed sequence was validated in both phantom and human subjects (12 healthy subjects and 15 patients who were referred for a clinical cardiac MR exam) and compared with saturation recovery single‐shot acquisition (SASHA) and modified Look‐Locker inversion recovery (MOLLI). Results: Phantom T1 measured by the proposed sequence had excellent agreement (R2 = 0.99) with the ground‐truth T1 and was insensitive to heart rate. In both healthy subjects and patients, the proposed sequence yielded nine left‐ventricular T1 maps per volume in less than 2 minutes (healthy volunteers: 1.8 ± 0.4 minutes; patients: 1.9 ± 0.2 minutes). The average T1 of whole left ventricle for all healthy subjects and patients were 1560 ± 61 and 1535 ± 49 ms by SASHA, 1208 ± 42 and 1233 ± 56 ms by MOLLI5(3)3, and 1397 ± 34 and 1433 ± 56 ms by the proposed sequence, respectively. The corresponding coefficient of variation of T1 were 6.2 ± 1.4% and 5.8 ± 1.6%, 5.3 ± 1.1% and 5.1 ± 0.8%, and 4.9 ± 0.8% and 4.5 ± 0.8%, respectively. Conclusion: The proposed sequence enables quantification of whole heart T1 with good accuracy and precision in less than 2 minutes during free breathing. [ABSTRACT FROM AUTHOR]

We developed a thermodynamic model to explore the joint solubility of Mg, Si, and O in liquid Fe on the basis of high‐pressure metal‐silicate partitioning data in the literature, with more Mg kept in the metal when Si and O are present. With <1.7 ± 0.5 wt% Mg, the metal in the young Earth's core retains Mg as the core evolves and crystallizes SiO2. Higher Mg concentrations require either the late addition of metal that equilibrated with silicate in a super‐liquidus magma ocean or the assimilation of silicate into the core at the time of a giant impact. Above 1.7 wt% Mg, (Mg,Fe)‐silicate melts also exsolve from the core and transfer core‐hosted elements to the mantle. Fractional crystallization of the core‐derived silicate melts in the core or at the core‐mantle boundary could, additionally, yield a persistent molten silicate layer that could also contribute to ultralow velocity zone formation in the lowermost mantle. Plain Language Summary: Some think that crystallization of oxide in the liquid core, either MgO or SiO2, could have been responsible for driving core convection and geodynamo since early Earth times, at least until iron started crystallizing the inner core. However, the joint solubility of Mg, Si, and O in liquid Fe has not been explored yet. Here we developed a thermodynamic model to examine the exsolution of MgO and SiO2 from liquid Fe at core‐mantle boundary (CMB) pressure based on earlier experimental data on metal‐silicate partitioning. Our main findings are that (1) more Mg is retained in the presence of Si and O in metal; (2) with <1.7 wt% Mg, the core expels solid SiO2 but not MgO; and (3) with higher Mg, magnesium silicate melt also exolves and transfers core‐hosted elements to the mantle. The seismologically observed molten silicate layer above the CMB may have been originally derived from the core. Key Points: Mg uptake in liquid iron is controlled by the liquid's Si content; silicate Mg is reduced by Si in the metalIf the core later expelled Mg ingested while accreting as (Mg,Fe)‐silicate, it could transfer siderophile trace elements back to the mantleULVZs at the base of the mantle could be related to fractional crystallization of (Mg,Fe) silicate expelled by the core [ABSTRACT FROM AUTHOR]

It is controversial whether communities are saturated with species, or have vacant niches. The prevalence of vacant niches and the processes likely to promote their existence are poorly known.We used a process‐based forest gap‐model to simulate plant community dynamics in 11 sites along a climatic gradient across central Europe. We then used hypervolume analyses to study the existence of vacant niches (seen as empty volumes in the trait space of local species pools and communities), and we tested for the effect of abiotic (environmental filtering) and biotic (competition) processes on the functional hypervolumes along the climatic gradient. Last, we performed invasion simulations to assess the invasibility of detected vacant niches.Our results suggest that empty volumes in trait space are common, can arise from both abiotic and biotic processes and are more likely in cold climates. We also showed that most vacant niches are invasible.Synthesis. Our work supports the view that niche space is unsaturated, and that many viable ecological strategies are absent from these forest communities. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

The detailed examination of low contrast image is a challenging issue. Thus, it makes difficult for the viewer to bring out the detailed features of the image. Histogram equalization (HE) is an efficient way to intensify the contrast of images. However, classical HE techniques result in immoderate intensification. Hence, an efficient contrast enhancement algorithm called quadrant dynamic clipped HE with gamma correction is proposed. This transformation addresses both over‐enhancement and fine detail preservation, which ensures no false contouring. In the proposed method, histogram of the input image is partitioned into four sections using its mean value. Histogram clipping and gamma correction is used to control the color enhancement rate. Then, clipped subhistogram is equalized independently and then they combined together to form an enhanced image. The performance assessment of the proposed and other existing methods is evaluated in terms of entropy, contrast, colorfulness, and saturation. Test results demonstrates that the proposed method outperforms the other existing HE methods in terms of preserving entropy, colorfulness, saturation, and obtaining uniform degree enhancement. [ABSTRACT FROM AUTHOR]

In this paper, we study the following problem proposed by Barrus, Ferrara, Vandenbussche, and Wenger. Given a graph H and an integer t, what is satt(n, R(H)), the minimum number of edges in a t-edge-colored graph G on n vertices such that G does not contain a rainbow copy of H, but adding to G a new edge in any color from t {1, 2, ..., } creates a rainbow copy of H? Here, we completely characterize the growth rates of satt(n, R(H)) as a function of n, for any graph H belonging to a large class of connected graphs and for any t ≥ e (H). This classification includes all connected graphs of minimum degree 2. In particular, we prove that satt (n, R(Kr)) = Θ( n log n), for any r ≥ 3 and t ≥ (r2), thus resolving a conjecture of Barrus, Ferrara, Vandenbussche, and Wenger. We also pose several new problems and conjectures. [ABSTRACT FROM AUTHOR]

The thermal conductivity of soils is an important parameter in environment, earth science and engineering applications. A new thermal conductivity model based on the Fredlund and Xing model was proposed to mimic the thermal conductivity of fine‐textured soils from dryness to full saturation. However, the use of a measured thermal conductivity value at a certain saturation to calculate the parameter of the thermal conductivity model reduces the ease of use. Therefore, the objective of this study was to use multiple linear regression (MLR) and artificial neural networks (ANN) to improve the thermal conductivity model. The performances of the MLR‐based model and ANN‐based model were evaluated and compared with measured data and three existing empirical models at different saturation ranges. The results showed that the MLR‐based model and ANN‐based model performed best at low saturations, the ANN‐based model performed best at saturations between 0.01 and 0.6, and the Johansen model showed the best fit to the measured data at saturations of above 0.6. In general, among the models, the ANN‐based model performed best from dryness to full saturation (root mean square error (RMSE) = 0.098 Wm−1 K−1 and average absolute deviation (AAD) = 0.071 Wm−1 K−1), followed by the MLR‐based model (RMSE = 0.110 Wm−1 K−1 and AAD = 0.081 Wm−1 K−1). The MLR‐based model and ANN‐based model are promising for the accurate calculation of the thermal conductivity of fine‐textured soils from dryness to full saturation and can be incorporated into the numerical modelling of heat and mass transfers. Highlights: The ANN‐based model performed best among five models from dryness to full saturation, followed by the MLR‐based model.The MLR‐based model and ANN‐based model showed the best fit to the measured data at low saturations.The ANN‐based model showed the best fit to the measured data at saturations between 0.01 and 0.6.The Johansen (1975) model showed the best fit to the measured data at saturations of above 0.6. [ABSTRACT FROM AUTHOR]

Since the beginning of the 21st century, there has been a surge in interest in color research (and in sensory marketing in general). In addition to discussing emerging color research contained in this special issue, this article also provides a discussion of theoretical frameworks for understanding color and provides technical guidelines for creating color stimuli. These guidelines include a discussion of the three dimensions of color (hue, saturation, and value) and provide researchers with guidance for controlling these dimensions when creating color stimuli. Additionally, this article discusses additive (red, green, blue) versus subtractive (cyan, magenta, yellow, and key) color models, gamut, and other considerations, such as screening participants for colorblindness, that future researchers may find useful for conducting rigorous color research. [ABSTRACT FROM AUTHOR]

Summary: In this article, the adaptive tracking control problem is considered for a class of uncertain nonlinear systems with input delay and saturation. To compensate for the effect of the input delay and saturation, a compensation system is designed. Radial basis function neural networks are directly utilized to approximate the unknown nonlinear functions. With the aid of the backstepping method, novel adaptive neural network tracking controllers are developed, which can guarantee all the signals in the closed‐loop system are semiglobally uniformly ultimately bounded, and the system output can track the desired signal with a small tracking error. In the end, a simulation example is given to illustrate the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

Aim: Regional diversity can increase owing to either the packing of species within regional niche space or the expansion of regional niche space. Yet, the primary factors dictating these dynamics remain poorly understood. Here, we assess the relative influence of current environmental conditions (net primary productivity, NPP) versus historic environmental stability over the Last Glacial Maximum on niche filling patterns of vertebrates (mammals, birds, amphibians and reptiles) in the Australian Wet Tropics (AWTs). Location: Australian Wet Tropics. Taxon: Vertebrates (mammals, birds, amphibians and reptiles). Methods: We measured patterns of niche filling (niche packing vs. niche expansion) as the standardized departure of observed functional diversity (FD) from its null expectation. We fitted spatial models for vertebrates, and for each constituent class (mammals, birds, amphibians and reptiles) separately, to evaluate the relative effects of NPP and environmental stability on species richness and niche filling patterns. Results: Historical environmental stability had a greater effect than NPP on species richness and niche filling patterns. However, the directionality of this effect depended on phylogenetic scale, with vertebrates exhibiting niche packing while each constituent class (except reptiles) exhibited niche expansion with increasing environmental stability. Main Conclusion: Intra‐class competition presumably leads to niche differentiation and expansion, whereas the overlap of functional traits among species from different classes leads to niche packing. That environmental stability over millennia is associated with an expanding niche space across multiple vertebrate classes suggests that the accumulation of FD within communities requires long recovery times. [ABSTRACT FROM AUTHOR]

Many scientists and philosophers of science have argued that metaphysical naturalism and methodological naturalism represent distinct and separable philosophical commitments. This claim is true in the sense that metaphysics and epistemology reflect different philosophical projects. The major question of interest to psychologists, however, is whether at the pragmatic level of research designed to discover the psychological sphere in which we live our lives, the metaphysical and the methodological realms are so tightly interwoven that some important aspects of our humanity cannot be faithfully revealed without distortion, or even missed altogether. This paper argues that, in light of its intellectual origins, methodological naturalism is informed by metaphysical naturalism at the level of its formulation, and, thereby, is by its nature more apt to reveal phenomena of certain ontological types and less apt to faithfully reveal phenomena of other ontological types. In this sense, metaphysical naturalism cannot help but subtly shape psychological investigation and thus insert itself to some degree into our understanding of many important psychological phenomena. The work of the French phenomenologist Jean‐Luc Marion, particularly his concept of "saturated phenomena," is briefly discussed by way of a call for greater methodological openness in psychological research – an openness that will permit psychological scientists to better "save the phenomena" in their accounts of human experience. [ABSTRACT FROM AUTHOR]

The effects of common anaesthetics on the hue, saturation and brightness measurements of the poeciliid fish Girardinus metallicus were investigated in two experiments. For both experiments the coloration of four body regions was measured from digital images of the same males obtained under three conditions: (1) control (in a water‐filled chamber); (2) anaesthetised with MS‐222; and (3) anaesthetised with eugenol (clove oil). In experiment 1 anaesthetised fish were photographed out of water. In experiment 2 all photographs were taken in a water‐filled chamber. Anaesthetics altered coloration in both experiments. In the more methodologically consistent experiment 2 we found significantly different hue, increased saturation and decreased brightness in anaesthetic v. control conditions, consistent with darkening caused by the anaesthetics. The body regions differed in coloration consistent with countershading but did not differentially change in response to anaesthesia. These findings suggest that photographing fish in a water‐filled chamber without anaesthetic is preferable for obtaining digital images for colour analysis and that multiple body regions of fish should be measured when assessing coloration patterns meaningful in behavioural contexts, to account for the gradients caused by countershading. We are encouraged that some researchers employ such methods already and caution against using anaesthetics except when absolutely necessary for immobilisation. [ABSTRACT FROM AUTHOR]

This paper investigated the effects of luminance, contrast and saturation of HDR video presented on QLED display on visual system. Results showed that mainly, contrast and saturation influenced visual neural systems controlling eye movements, as well as subjective evaluation of display quality and viewing preference, while luminance generally had no significant influence. [ABSTRACT FROM AUTHOR]

Two parameters that play the most important role in the appraisal of environmental risk performance at carbon dioxide (CO2) storage sites are the prospective impact of the pore pressure increase and CO2 saturation. In this context, this study investigates the spatiotemporal evolution of pressure buildup and CO2 saturation as a function of flow region's size, average porosity and permeability, and heterogeneity, as well as the injection rate and total volume of injected fluid. The practical importance of this study is to investigate the factors that affect the extent of pressure buildup and areal extent of CO2 plume both during and after injection, which will impact risk assessment as well as influence effective monitoring operations. This study pursues the above objective using two risk metrics that are based on numerical simulations and illustrated using representative models of three realistic storage sites with varying volumetric storage potential and geological settings, all with open geologic systems. The two metrics (the spatiotemporal extent of pressure buildup and CO2 saturation plume, respectively) used in this study are able to capture the geologic (structural and petrophysical) and operational complexities that cannot be incorporated into analytical or semianalytical solutions. The results of this study suggest that in addition to the average permeability, the areal extent of the pressure buildup during the injection period is strongly related to the injection rate, whereas the postinjection period may be more strongly influenced by the reservoir heterogeneity. The areal extent of the saturation plume during active injection is highly correlated to the mass of injected fluid, and the postinjection behavior is impacted by the shape of the reservoir–seal interface. These findings are consistent with other recent studies by the National Risk Assessment Partnership (NRAP) on characteristic reservoir behavior. The results have been used to generate pressure and saturation plume profiles (over time) that can be used to support risk‐based decision making. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Natural gas hydrates were discovered in the Muli area of the Qinghai–Tibetan Plateau permafrost, which is an area of alpine permafrost in the midlatitudes. Resistivity models were employed to understand the distribution and accumulation mechanism of gas hydrates in the Muli area, as these models are suitable for use in detecting the presence and amount of pore‐ and fracture‐filling gas hydrates in consolidated rocks, and geophysical logs were used to constrain gas hydrate saturation. The results show that resistivity logs are sensitive to gas hydrate saturation in consolidated rocks in the Muli area. Geophysical log analysis enabled the discovery of eleven pore‐filling gas hydrate reservoirs (total thickness: 21.95 m) and nine fracture‐filling gas hydrate reservoirs (total thickness: 90.55 m). It is hypothesized that gas accumulation is more likely to occur in fractures within mudstones due to good permeability and sealing properties and that fracture‐filling gas hydrates are more likely to occur than pore‐filling gas hydrates. Poor preservation conditions may thus be the key factor in the absence of gas hydrates in the eastern part of the study area. Evidence from geophysical logs shows that the upper boundary of the gas hydrate stability zone in the Muli area is at a depth of 133.25 m and that the lower boundary is deeper than 400 m. The results of this study are useful for further gas hydrate exploration in alpine permafrost at the midlatitudes. Key Points: Resistivity logs are more sensitive to gas hydrate saturation than compressional‐wave velocity logs in consolidated rocks of the Muli areaResistivity models of pore‐ and fracture‐filling gas hydrate reservoirs are used to detect gas hydrates in consolidated rocksGas hydrate accumulation in the Muli area is affected by faults, lithology, and the gas hydrate stability zone [ABSTRACT FROM AUTHOR]

Temperature effects on the fatty acid (FA) profiles of phytoplankton, major primary producers in the ocean, have been widely studied due to their importance as industrial feedstocks and to their indispensable role as global producers of long‐chain, polyunsaturated FA (PUFA), including omega‐3 (ω3) FA required by organisms at higher trophic levels. The latter is of global ecological concern for marine food webs, as some evidence suggests an ongoing decline in global marine‐derived ω3 FA due to both a global decline in phytoplankton abundance and to a physiological reduction in ω3 production by phytoplankton as temperatures rise. Here, we examined both short‐term (physiological) and long‐term (evolutionary) responses of FA profiles to temperature by comparing FA thermal reaction norms of the marine diatom Thalassiosira pseudonana after ~500 generations (ca. 2.5 years) of experimental evolution at low (16°C) and high (31°C) temperatures. We showed that thermal reaction norms for some key FA classes evolved rapidly in response to temperature selection, often in ways contrary to our predictions based on prior research. Notably, 31°C‐selected populations showed higher PUFA percentages (including ω3 FA) than 16°C‐selected populations at the highest assay temperature (31°C, above T. pseudonana's optimum temperature for population growth), suggesting that high‐temperature selection led to an evolved ability to sustain high PUFA production at high temperatures. Rapid evolution may therefore mitigate some of the decline in global phytoplankton‐derived ω3 FA production predicted by recent studies. Beyond its implications for marine food webs, knowledge of the effects of temperature on fatty acid profiles is of fundamental importance to our understanding of the mechanistic causes and consequences of thermal adaptation. [ABSTRACT FROM AUTHOR]

High dynamic range imaging (HDRI) by bracketing of low dynamic range (LDR) images is demanding, as the sensor is deliberately operated at saturation. This exacerbates any crosstalk, interpixel capacitance, blooming and smear, all causing interpixel correlations (IC) and a deteriorated modulation transfer function (MTF). Established HDRI algorithms exclude saturated pixels, but generally overlook IC. This work presents a calibration method to estimate the affected region from saturated pixels for a color filter array (CFA) sensor, using the native CFA as a matched filter. The method minimizes color crosstalk given a set of candidates for proximity regions, and requires no special setup. Results are shown for a 21‐bit HDR output image with improved color fidelity and reduced noise. The calibration reduces IC in the LDR images and is performed only once for a given sensor. The improvement is applicable to any HDRI algorithm based on CFA image bracketing, irrespective of sensor technology. Generalizations to subsaturated and supersaturated pixels are described, facilitating a suggested irradiance‐exposure dependent point spread function charge repatriation strategy. [ABSTRACT FROM AUTHOR]