Search

We conduct coupled thermo-hydro-mechanical modeling of a KBS-3V repository design in crystalline rocks, using data and conditions from the Forsmark in Olkiluoto repository sites in Sweden and Finland. The study focuses on repository performance related to the impact of thermal and hydraulic evolution on the potential for thermal–mechanical damage to underground repository excavations. For the designs and conditions considered at the Forsmark and Olkiluoto repository sites, the simulations show a peak temperature well under the adopted performance target of a 100°C maximum temperature, whereas there is still a high potential for thermal–mechanical damage to the KBS-3V waste deposition holes. The thermal–mechanical damage is much more likely if rock permeability is so low that it delays saturation and swelling of bentonite-clay-based backfill beyond the time for the thermal–mechanical peak, which occurs 50 to 100 years after nuclear waste deposition. We also found that sidewalls of the KBS-3V emplacement tunnels are vulnerable to tensile fracturing due to the combined effect of thermal stressing and backfill swelling. The study highlights a strong interaction between bentonite-based backfill and host rock through capillary suction along with induced rock desaturation. A careful design and selection of the bentonite-clay-based backfill materials for KBS-3V tunnels and deposition holes can facilitate a timely saturation and backfill swelling that in turn can minimize thermal–mechanical damage.

This work considers the isothermal process of incompressible viscous fluid filtration in an oil-saturated, fractured-porous reservoir. A study of the pressure and water saturation distribution process is carried out for a case in which a production well is put into operation. For this problem, i.e., a mathematical model in a two-dimensional formulation, a numerical method and a parallel algorithm are proposed. The mathematical model of two-phase filtration is written in accordance with the classical laws of continuum mechanics and Darcy's law and also includes a function of fluid exchange between low-permeability pores and high-permeability natural fractures within the framework of the Warren–Root model. The numerical solution is based on the finite-difference method and a splitting scheme of physical processes and spatial coordinates. For a split system with respect to piezoconductivity, an implicit finite-difference scheme with fixed saturations is constructed, and with respect to saturation transfer, explicit and implicit difference schemes are constructed. For parallel implementation of the developed numerical approach, a method based on geometric parallelism is selected. Testing of the developed method is performed using the example of calculating liquid mass transfer for a wide range of parameters. To verify the model, the obtained calculated pressure curves are compared with field data recorded by a deep-well measuring device. The results allow for estimation of the distribution of reservoir pressure and water saturation depending on the permeability of the fracture set and the pore part. The obtained results allow for monitoring of well operations, reducing unexpected accident risks and optimizing the development system in order to increase oil production in fractured-porous reservoirs. Computational experiments confirm the efficiency of the developed numerical algorithm and its parallel implementation. [ABSTRACT FROM AUTHOR]

In this paper we investigate the Riemannian extensibility of saturation phenomena treated first in the Euclidean framework by Brandolini et al. [Sharp estimates and saturation phenomena for a nonlocal eigenvalue problem. Adv Math (N Y). 2011;228(4):2352–2365.]. The saturation problem is formulated in terms of the first eigenvalue of the perturbation of the Laplace-Beltrami operator by the integral of the unknown function: the first eigenvalue increases with the weight affecting the integral up to a finite critical value and then remains constant, i.e. it saturates. Given a Riemannian manifold with certain curvature constraints, by using symmetrization arguments and sharp isoperimetric inequalities, we reduce the general problem to a variational one, formulated on either positively or negatively curved Riemannian model spaces; in addition, the possible scenarios for the optimal domains turn to be either geodesic balls or the union of two disjoint geodesic balls. We then explicitly compute the eigenvalues and eigenfunctions in terms of the radii, curvature and weight. A sufficient condition (incompatibility of a system of nonlinear equations involving special functions) is given that implies similar saturation phenomena to the Euclidean case. Due to its highly nonlinear character of the reduced problem (arising from the presence of curvature and special functions), we provide only partial answers to the original problem. However, both analytical computations and numerical tests suggest that the required incompatibility always persists. In addition, in the limit cases when the curvature tends to zero (for both positive an negative curvature), our results reduce to the Euclidean version. [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]

There has been a recent explosion of articles on minimum sample sizes needed for analyzing qualitative data. The purpose of this integrated review is to examine this literature for 10 types of qualitative data analysis (5 types of saturation and 5 common methods). Building on established reviews and expanding to new methods, our findings extract the following sample size guidelines: theme saturation (9 interviews; 4 focus groups), meaning saturation (24 interviews; 8 focus groups), theoretical saturation (20–30+ interviews), metatheme saturation (20–40 interviews per site), and saturation in salience (10 exhaustive free lists); two methods where power analysis determines sample size: classical content analysis (statistical power analysis) and qualitative content analysis (information power); and three methods with little or no sample size guidance: reflexive thematic analysis, schema analysis, and ethnography (current guidance indicates 50–81 data documents or 20–30 interviews may be adequate). Our review highlights areas in which the extant literature does not provide sufficient sample size guidance—not because it is epistemologically flawed, but because it is not yet comprehensive and nuanced enough. To address this, we conclude by proposing ways researchers can navigate and contribute to the complex literature on sample size estimates. [ABSTRACT FROM AUTHOR]

ABSTRACT 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]

Under the long-term influence of overburden load and water infiltration, coal undergoes creep damage, and the disturbance caused by mining activities can lead to sudden instability, triggering geological disasters such as mine flooding. Therefore, this study prepared four types of coal samples with different saturations under creep damage conditions and conventional coal samples. A comparative study was conducted using uniaxial compression tests to examine the deterioration characteristics of physical and mechanical parameters, failure modes, and energy evolution patterns in these two types of coal samples. Additionally, a microscopic deterioration model of coal samples under the combined influence of water and creep damage was constructed to elucidate the mechanism of creep damage on the deterioration of mechanical properties in water-containing coal samples. The research findings indicate that coal samples affected by creep damage and conventional coal samples exhibit significant consistency in mechanical parameters and energy evolution patterns. Specifically, an increase in saturation is positively correlated with peak stress, elastic modulus, and dissipated energy. Conversely, peak strain, total input energy, and elastic strain energy are negatively correlated with rising saturation levels. Under the same saturation conditions, the change in mechanical parameters and energy characteristics is more pronounced in creep-damaged coal samples. Furthermore, the stress-strain curves of both coal sample types exhibit prolonged compaction stages, shortened elastic stages, and more significant yield stages. Under equivalent saturation levels, the stress-strain trends in creep-damaged coal samples show more substantial variations. Upon loading and failure, the conventional coal sample transitions from single inclined plane shear failure to tension-shear mixed failure as the saturation increases. Conversely, the creep-damaged coal sample shifts from "X"-type conjugate shear failure and tension-shear mixed failure to tension failure, signifying a tendency toward more complex failure modes. In cases where the coal sample has a water saturation of 41%, the deterioration of its mechanical parameters is primarily attributed to creep damage. However, when the water saturation reaches 41–100%, water plays a dominant role in the deterioration of the coal sample's mechanical parameters. After experiencing creep damage, the internal micro-cracks of the coal sample are extensively developed, which is also the primary factor contributing to the deterioration of the coal sample's mechanical properties and an increased proportion of dissipated energy. [ABSTRACT FROM AUTHOR]

In this paper, a data processing approach was developed to accurately extract the ring-down time and amplitude of the saturated cavity ring-down (CRD) signal; both were utilized to determine simultaneously the high reflectance and residual transmittance of highly reflective (HR) mirrors with a dual-channel CRD configuration. The influence of saturation was eliminated by deleting the beginning saturated data points of the saturated CRD signal and fitting the remaining non-saturated CRD signal to a single-exponential function. By comparing the reflectance/transmittance measurement results of HR samples obtained via data processing of saturated CRD signals and via single-exponentially fitting non-saturated CRD signals with utilization of neutral density filter(s) to eliminate saturation, it was found that the reflectances obtained with both methods were in excellent agreement, while the residual transmittance obtained with the saturated CRD signal was more accurate than that obtained with the neutral-density-filter-attenuated non-saturated CRD signal. The proposed data processing method eliminated the need to use the neutral density filters, therefore avoiding the adding of the optical density error to the uncertainty of residual transmittance measurement and improving the measurement accuracy. The proposed data processing method also extended the dynamic range of the dual-channel CRD scheme for simultaneous measurement of reflectance, transmittance and optical loss. [ABSTRACT FROM AUTHOR]

This article presents an improved data-driven adaptive control structure to address the problem of input and output saturation in unknown nonlinear systems with multiple inputs and multiple outputs. In the suggested structure, a virtual model of the controlled system is initially built utilizing a multi-layered group method of data handling neural network. The control signal is then applied to this virtual model to predict the output before being applied to the system. If the predicted output is saturated, the control signals are readjusted to prevent saturation and are then applied to the system. By using this proposed structure, the performance of model-free adaptive control against input/output saturation phenomena is improved and the occurrence of saturation is prevented. Based on Lyapunov's theory, the stability of the suggested structure is proven. The controller has been applied to an interconnected three-tank system and a subway train which results clearly illustrate the advantages of the suggested method over the traditional form of model-free adaptive control design. [ABSTRACT FROM AUTHOR]

The accurate classification of palm sugar varieties is essential for maintaining product quality and ensuring consumer satisfaction within the food industry. This study proposes a hybrid model that integrates feature Hue, Saturation, and Lightness (HSL) colour space, feature Gray-Level Co-occurrence-Matrix (GLCM) texture analysis, and Fuzzy K-Nearest Neighbors (FKNN) algorithms to classify different categories of palm-sugar, including aren texture, coconut texture, and lontar texture varieties. The hybrid approach leverages advanced image processing techniques to extract and analyze critical texture and colour features, achieving a classification accuracy of 98%. The results underscore the potential of this model to enhance operational efficiency, promote product standardization, and support fair market practices in the palm sugar industry. By providing an automated and accurate classification system, this research contributes to both the economic optimization of production processes and the transparency of product quality in the market. Future research related to palm sugar on real-time deployment of the system in industrial environments is essential, with potential integration into automated sorting and packaging systems to further streamline operations. [ABSTRACT FROM AUTHOR]

Gillnets are widely used in research and commercial fishery activities. As passive gear, gillnets can be selective and dependent on the diel migration of fish. In areas with limited littoral extent, inshore–offshore migration may cause bias in the gillnet catch. Our hypothesis was that some factors, such as gillnet saturation, fish depletion, or chemical cues, could be the cause of the bias. We used a total of 66 CEN gillnets deployed at Římov Reservoir parallel to the shore at different positions of littoral-pelagic gradient. Individual fish direction was recorded from inshore, offshore, or unknown direction (i.e., entangled fish). A total of 5791 fishes from nine different species were caught. For most fish, it was possible to determine their directivity, and most fish were captured in littoral or first pelagic gillnets. Shallower and deeper benthic gillnets differed in their bleak (Alburnus alburnus) catch. No significant differences were found between fish directions. At the species level, only asp (Leuciscus aspius) and ruffe (Gymnocephalus cernua) showed differences between the captured directions in one case. The results support the assumption that gillnet capture is a random process that to a great extent is connected to random local movements. This is good news for fish monitoring projects. Sampling catch is likely to reflect true changes in the fish community, and not the effects of the deployment of the sampling gear. The experiment also showed that fish directivity statistics can be used for investigation of fish behavior and gear performance. [ABSTRACT FROM AUTHOR]

In this paper, we perceive boredom as a potential resource for creativity in qualitative research. We present three main arguments. First, boredom is often an inevitable stage on the way to research excitement and can even serve as an important clue leading to analytic surprises. Second, there is a methodological need to reflect on boredom in order to understand the researcher’s perception of meaningfulness and meaninglessness. Particularly, we show how the ‘interview society’, characterized by the dominance of the therapeutic discourse, shapes researchers’ expectations regarding what is considered ‘interesting’ or ‘boring.’ Finally, the researcher’s experience of boredom may provide insights into the very phenomenon under investigation. We flesh out these arguments by showing how the researcher’s boredom during interviews reflects the interviewees’ emotional style, expected of (women) managers in the neoliberal culture: emotional restraint and a façade of rationality and objectivity. [ABSTRACT FROM AUTHOR]

The increase in the use of molecular methodologies in systematics has driven the necessity for a comprehensive understanding of the limitations of different genetic markers. Not every marker is optimal for all species, which has led to multiple approaches in the study of the taxonomy and phylogeny of polyclad flatworms. The present study evaluates base-substitution rates of nuclear ribosomal (18S rDNA and 28S rDNA), mitochondrial ribosomal (16S rDNA), and protein-codifying (cytb , cox1) markers for this taxonomic group, with the main objective of assessing the robustness of these different markers for phylogenetic studies. Mutation rates and Ti/Tv ratios of the other markers were assessed for the first time. We estimated substitution rates and found cytb to be the most variable, while 18S rDNA was the least variable among them. On the other hand, the transition to transversion (Ti/Tv) ratio of the different genes revealed differences between the markers, with a higher number of transitions in the nuclear gene 28S and a higher number of transversions in the mitochondrial genes. Lastly, we identified that the third codon position of the studied protein-codifying genes was highly variable and that this position was saturated in the cox1 marker but not in cytb. We conclude that it is important to assess the markers employed for different phylogenetic levels for future studies, particularly in the order Polycladida. We encourage the use of mitochondrial genes cytb and 16S for phylogenetic studies at suborder, superfamily, and family levels and species delimitation in polyclads, in addition to the well-known 28S and cox1. [ABSTRACT FROM AUTHOR]

Suppose that is some nonempty set of finite groups. A group is saturated with groups from if each finite subgroup of lies in a subgroup isomorphic to an element of . We prove that a periodic group with locally finite centralizers of involutions which is saturated with simple unitary groups of degree 4 over finite fields of fixed odd characteristic is isomorphic to a simple unitary group of degree 4 over some locally finite field of characteristic . [ABSTRACT FROM AUTHOR]

In this article, I study Guy Debord's critical discourse, particularly his landmark essay The Society of the Spectacle. He underlines here the symbolic desert produced by modern societies. I stress the uniqueness of his perspective, to the extent that such desert stems from a situation of overabundance and excess, and not from a specific void or absence. This desert constitutes a space saturated with images and signs: it asserts the rule of the superfluous and the inconsequential. Moreover, this discourse was rooted in the Glorious Thirties, which were characterized by a strong economic growth. It must therefore be placed within a historical and social context that is quite different from twenty first Century French society. Contemporary France is marred by contrast by unemployment and precariousness as well as by huge socio-economic inequalities. The endless production of media images contradicts therefore the deep shortcomings of social reality. Finally, the concept of the Spectacle, for Debord, did not include yet the overwhelming power of new technologies. These technologies have greatly expanded the influence of images within the social and cultural sphere by making them instantaneous and readily available. The same process has also increased significantly the potential alienation and isolation of man. [ABSTRACT FROM AUTHOR]

All qualitative researchers are familiar with the idea of saturation: that researchers should continue to collect and/or analyze data until nothing new is being added to their arguments or conclusions. Saturation is, however, used and understood in a variety of ways, often appearing as an unevidenced and dogmatic statement seeking to justify that a piece of research is complete. This article explores the application of the idea of saturation in qualitative research, noting its association with grounded theory and the particular interest taken in it by health researchers. It concludes that it is both a misunderstood and an overworked concept. [ABSTRACT FROM AUTHOR]

In response to the fairness issue arising from the unequal delay of vehicles in different phases at intersections and considering the actual situation of small and variable delays for vehicles in low-saturation intersection phases, this paper proposes the concept of "sacrificing efficiency for fairness". Firstly, the universality of unfair delay phenomena at intersection phases is explained, especially at low-saturation intersections where the fluctuation in phase delays is 1.87 times higher than at other intersections. Then, a fairness evaluation index is constructed using information entropy, and the feasibility of the proposed approach is demonstrated. Subsequently, a signal optimization model that balances efficiency and fairness is proposed. Finally, the proposed model is validated through case studies, showing that it not only simultaneously considers efficiency and fairness but also has minimal impact on efficiency. Moreover, the changes to timing schemes in the efficiency model are much smaller compared to the model that only considers fairness. Sensitivity analysis reveals that the model performs better under low-saturation intersection conditions. [ABSTRACT FROM AUTHOR]

We address the question of finding algebraic properties that are respectively equivalent, for a morphism between algebraic varieties over an algebraically closed field of characteristic zero, to be a homeomorphism for the Zariski topology and for a strong topology that we introduce. Our answers involve a study of seminormalization and saturation for morphisms between algebraic varieties, together with an interpretation in terms of continuous rational functions on the closed points of an algebraic variety. The continuity refers to the strong topology which is the usual Euclidean topology in the complex case and which comes from the theory of real closed fields otherwise. [ABSTRACT FROM AUTHOR]

An increasing number of brands have been redesigning their logos. While the manner of redesigning varies, some brands change only the logo color. This study examined the effect of changes in color saturation while brand logo redesigns on consumers’ brand attitudes. Saturation, which indicates the vividness of a color, gives consumers an impression of energy and dynamism. Therefore, we examined the impact of changes in brand logo color saturation on brand attitudes by enhancing perceptions of brand energy. Three studies revealed that 1) a highly saturated logo enhances consumers’ perception of brand energy; 2) increasing saturation when changing the logo color increases brand energy perception, which in turn increases attitude toward the brand; and 3) the effect of brand energy perception on attitude toward the brand is stronger for international brands than for domestic brands. This study, which clarified the relationship between the influence of saturation and brand attitude when a brand logo is redesigned, provides many suggestions for companies considering logo redesign.

When transporting and storing hydrocarbons, one of the main operational problems is the external and internal corrosive wear of the metal. A frequent cause of accidents in main and technological gas pipelines due to their stress corrosion cracking is the enrichment of the pipe body with hydrogen. Literature experimental data on the effect of hydrogen on the hardness of iron and low-carbon steels during their electrolytic saturation with hydrogen are analyzed. It is noted that the curves of changes in hardness in all the analyzed sources for all these materials have a similar form: at the initial stage of hydrogenation, the hardness increases, reaching its maximum, and then it declines to values close to the initial level follows. At the same time, the time to reach the maximum hardness decreases with the introduction of promoters into the electrolyte solution, which can be Na2S, As. Increasing the current density during electrolysis increases the value of the maximum hardness. The time to reduce the hardness to the initial level is approximately the same as the hydrogenation time required to achieve maximum hardness. Possible explanations of the regularities obtained by the authors are given. [ABSTRACT FROM AUTHOR]

In this paper, we introduce saturation and semisaturation functions of sequences, and we prove a number of fundamental results about these functions. Given a forbidden sequence u with r distinct letters, we say that a sequence s on a given alphabet is u -saturated if s is r -sparse, u -free, and adding any letter from the alphabet to an arbitrary position in s violates r -sparsity or induces a copy of u. We say that s is u -semisaturated if s is r -sparse and adding any letter from the alphabet to s violates r -sparsity or induces a new copy of u. Let the saturation function Sat (u , n) denote the minimum possible length of a u -saturated sequence on an alphabet of size n , and let the semisaturation function Ssat (u , n) denote the minimum possible length of a u -semisaturated sequence on an alphabet of size n. For alternating sequences, we determine both the saturation function and the semisaturation function up to a constant multiplicative factor. We show for every sequence that the semisaturation function is always either O (1) or Θ (n). For the saturation function, we show that every sequence u has either Sat (u , n) ≥ n or Sat (u , n) = O (1). For every sequence with 2 distinct letters, we show that the saturation function is always either O (1) or Θ (n). [ABSTRACT FROM AUTHOR]

Shengli Oilfield has abundant oil and gas resources， with multiple types of reservoirs， and logging evaluation plays an essential role in exploration and development. The development history and the characteristics of logging evaluation technologies for reservoirs were systematically reviewed to celebrate the institute's 60th birthday. Summarizing experience and predicting the future have positive significance for the development and application in the professional logging field. A series of mature evaluation technologies formed in three types of reservoirs， including conventional sandstone reservoirs， complex reservoirs， and unconventional shale reservoirs， were systematically summarized according to the characteristics and evaluation difficulties of reservoirs. For conventional sandstone reservoirs， a highly applicable identification technology for oil layers was systematically developed， and an innovative method for establishing electrical standards constrained by the lower limits of lithology and oil potential was developed under multi-layer joint testing conditions. In addition， a pioneering logging modeling technology was proposed based on different diagenetic zones. Various technologies were developed for complex reservoirs， including logging identification of sandstone lithology in steep slope zones， effectiveness evaluation of low-permeability sandstone reservoirs， and identification and evaluation of oil layers with low resistivity. For unconventional shale reservoirs， a logging evaluation technology of reservoir parameters was preliminarily developed to evaluate the storage properties and oil potential mainly based on two-dimensional nuclear magnetic resonance experiments. These logging evaluation technologies for different types of reservoirs reflected the combination of wellbore data and geological understanding， as well as the integration of rock physics and logging models， and they demonstrated the ability of logging to serve geology and reservoirs and achieved good application results. In the future， the remaining resources will mainly be distributed in hidden oil and gas reservoirs and deep layers. In order to meet the needs of exploration and development， it is necessary to strengthen the analysis of experimental data， gas logging， and testing production data， combine logging evaluation and geology， intensify the application of new logging technologies such as logging while drilling， imaging， and nuclear magnetic resonance， carry out comprehensive research and evaluation， and expand the evaluation and prediction of production capacity of oil layers from the perspective of evaluation objectives. Moreover， it is necessary to fully rely on expert experience to select samples and deepen the application of big data/artificial intelligence on the basis of conventional technologies， which will definitely achieve good results.

Discrete element simulation of triaxial compression test was carried out to study the effects of confining pressure and saturation on the macro and meso mechanical properties of gas hydrate bearing coal (GHBC). Firstly, the numerical models of three kinds of GHBC with different saturations were established by particle flow program PFC3D, with the cementation of hydrate simulated by parallel bonding model. Then, the meso mechanical parameters were calibrated by using the results of the physical triaxial test. The stress-strain curves of the physical tests agree with the simulated results, with the failure strength and strength parameter error rate within 10%, which verifies the reliability of the established numerical model. Furthermore, the triaxial tests of GHBC were performed under different confining pressures to analyze the macro and meso-mechanical characteristics such as the stress-strain curve, velocity field, contact force chain, coordination number and porosity. The results show that the discrete element simulation results agree well with the indoor test results, especially simulating the strain hardening characteristics of the sample. The velocity field reveals a higher dilatancy degree under low saturation and a higher contraction degree under the high confining pressure of the samples. There is no obvious difference in the main chain transfer direction at the failure strength under different saturations and confining pressures. The contact force, the number of contact force chains, as well as the coordination number increase with the increase of confining pressure and saturation, while the porosity tends to decrease, which enhances the strength of the samples. The friction is an important factor to maintain the stability of the meso mechanical system of the samples. The influence mechanism of saturation and confining pressure on the strength deformation and failure of GHBC is revealed from the microscale, which provides a theoretical reference for the discrete element simulation of GHBC triaxial test and for the prevention of coal and gas outburst by hydrate technology.

The temperature dependences of the thermoelectromotive force of chromium mono and disilicides in the temperature range 200℃÷+600℃ have been studied. For chromium disilicide, the dependence of the thermopower coefficient (α) on temperature (T) has three sections. Chromium monosilicide is characterized by a smooth increase in thermopower with increasing temperatures up to 200℃, and then its constancy. It was revealed that silicides rich in chromium atoms have lower thermopower values than silicides rich in silicon. The maximum thermo-EMF values of 110 μV/K and 190 μV/K were observed for chromium mono- and disilicides, respectively. It was revealed that for chromium silicides the dependence of the dimensionless parameter Q = Z∙T on temperature is linear. The possibility of predicting the technology of synthesis of semiconductor material with optimal thermoelectric properties using the dependence of thermopower on conductivity and the parameter Q on temperature is shown.

Parametric resonance is a complicated phenomenon that manifests itself in many areas. When subjected to parametric resonance, the amplitude of the flexible manipulator will increase abruptly, resulting in the rapid deterioration of working performance. Most conventional control methods are ineffective when approaching resonance. Because of this, a new method for suppressing the parametric resonance of the flexible manipulator is proposed. A novel parametric resonance absorber, characterized by controllable vibration parameters and adjustable nonlinear coupling parameters, is designed to strengthen quadratic modal coupling with the flexible manipulator and to construct a transfer tunnel for exchanging and dissipating parametric resonance energy. Dynamics equations of the controlled flexible arm mode and the parametric resonance absorber mode are derived, and the corresponding steady-state solutions of parametric resonance are solved. The saturation principle is revealed and implemented based on the stability analysis of the steady-state response of parametric resonance. With the help of the saturation principle, the parametric resonance response of the flexible manipulator can be effectively suppressed to a small amplitude by the proposed parametric resonance absorber. A series of numerical simulations and experiments have verified the proposed method’s effectiveness in suppressing the flexible manipulator’s parametric resonance. [ABSTRACT FROM AUTHOR]

This study reports the room temperature testing of an InGaAs/InP photodetector, biased under linear sweep and/or parametric bias voltage for both modulated, and unmodulated 1550 nm wavelength illuminations. Charge transport of the photo-generated carriers is probed under absorber's electric field manipulations via parametric control of applied bias, readout element, and light intensity. The device exhibits three different illumination intensity dependent current signatures. Speed of the employed device is enhanced under relatively stronger electric fields ensuring higher drift, and reduced transit times. A three order reduction in the gain setting of the readout element results in ∼ 235 times large peak-current under 20 times smaller pulsed illumination of 0.2 μ W . This electric field enhancement decreases rise, and fall times under pulsed illumination from 225 ns to 115 ns , and 1.553 μ s to 1.143 μ s , respectively. But, the large photodetection plausibility, and reduced transit times ensuring relatively fast speed comes at the expense of ~ 5 order high noise activity in the device. It is also inferred that, overall noise spectrum of the device is not decided by simple generational processes in the absorber, but through the actual proportion of photo-generated carriers taking part in the real charge transport. [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]

The robust control problem of permanent magnet synchronous motor (PMSM) is discussed in this paper. Both iron loss and voltage saturation are considered in the analysis process in order to close to the actual projects. A controller design method, which is called the Hamiltonian-based method, is proposed for the PMSM control system. The responses of each current component and speed are analyzed when load torque disturbance exists. The proposed controller enables the closed-loop system to have robust performance criteria without violating saturation. It is worth noting that a more general truncation-inequality technique is used to deal with saturation, which reduces the conservatism of parameter selection. In addition, the corresponding results are given for two special cases. When there is no saturation and no load torque disturbance, the system is asymptotically stable at the equilibrium point. Simulation results and experimental study show that the proposed method has good load disturbance suppression ability and can ensure the robust performance of the PMSM in EV driving systems. [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]

Soil physical properties derived from phase relationships such as void ratio, degree of saturation, water content, and unit weight conventionally are formulated and calculated under the implicit assumption that the volumes of the three soil phases (i.e., solid, water, and air) are independent and unaffected by interactions among phases. However, significant variations do occur, including variation in the unit weight of soil water resulting from adsorptive soil–water interactions and variation in void volume resulting from bulk swelling or shrinking with changes in moisture. The importance of accounting for soil–water interactions in calculating soil physical properties was examined by introducing a new variable-volume soil phase diagram, and was illustrated using experimental data from consolidation and shrinkage tests for silts, nonswelling clays, and swelling clays. Errors in calculating void ratio and soil unit weight in saturated consolidation tests using conventional phase relationships can be significant—as high as 48% relative error in void ratio and as high as 16% relative error in soil unit weight. Errors in calculating moisture ratio and saturation in shrinkage tests can be as high as 53% relative error in moisture ratio and 42% in saturation. The occurrence of maximum error is highly correlated with soil water content corresponding to the maximum amount of adsorbed water. Liquid limit (LL) and specific surface area (SSA) were identified as index properties that can be used to account for volume variations in phase calculations. Examples are provided to illustrate the implementation of the proposed variable-volume soil phase formulation using LL or SSA in practical problems. Analysis showed that for fine-grained soils, it is practically necessary to use general variable-volume phase relationships to define basic soil properties in lieu of the conventional phase relationships. [ABSTRACT FROM AUTHOR]

The accurate diagnosis of medical conditions from low-light images, particularly black-and-white x-rays, is impeded by challenges such as noise, constrained visibility, and a lack of detail. Existing enhancement methods often exacerbate these issues by introducing detail loss, color oversaturation, or higher noise levels. This paper proposes a novel U-Net-based Convolutional Neural Network (CNN) specifically developed to address these challenges in low-light black-and-white medical images. Our designed architecture employs skip connections within the U-Net framework to effectively balance noise reduction with detail information preservation. This makes it possible for the network to learn hierarchical image representations while retaining important features for diagnosis. The trained network accomplishes real-time image enhancement, enabling immediate visual improvement during diagnosis and perhaps assisting radiologists in making faster and more accurate findings. Our approach illustrates a significant improvement in image quality and outperforms traditional methods in terms of noise reduction and detail preservation. This study holds significant potential to improve medical image analysis and diagnosis, potentially leading to enhanced patient care and earlier interventions. [ABSTRACT FROM AUTHOR]

Objective of the study: to investigate the possibility of predicting the early neonatal adaptation of newborns based on clinical and instrumental data that assesses the status of pregnant woman with COVID-19 infection and the fetus. Materials and methods. The participants of the study were 58 pregnant women with a diagnosis of COVID-19 (group A) and 40 women with a physiological course of pregnancy (group B), as well as their newborns. In addition to the analysis of standard examinations results, perinatal consequences for the mother and the fetus/newborn, the association between the saturation level (SрO2 ) in the pregnant woman, the short-term heart rate variability (STV) according to cardiotocography data of the fetus and the assessment of the newborn according to the Apgar scale was studied. Results. The SрO2 level was 95% or more in 87.9% of infected pregnant women, in 12.06% it was 90–94% (critical for pregnant women). 10.3% of pregnant women needed intensive therapy and respiratory support, 69% of women had inflammatory changes in the chest organs (pneumonia, etc.). Cardiotocography showed a significant difference in the type of basal heart rate between the groups (χ2 = 14.9055, p = 0,00058) and STV (7.78 ± 2.56 vs 8.39 ± 2.03 ms) in groups A and B, respectively (U = 687, p = 0.00022). The Apgar scale index in groups A and B was 6.48 ± 2.39 and 8.05 ± 0.54 points, respectively (χ2 = 21.933, df = 4). 20% of newborns in group B had 7 points in the first minute, 80% had 8 points or more. 51.85% of newborns in group A had scored 7 points or less (F = 0.00246, p < 0.05, odds ratio 4.308, 95% CI 1.681 – 11.037). 10.34% of newborns required intensive care, 5.17% – administration of surfactant, 1.72% – artificial lung ventilation. Regression analysis showed that the Apgar scale indicator at the first minute of life in newborns in group A depends on the SрO2 level of the pregnant woman (Y = 0.89X1 – 79.19), as well as on the STV (Y = 0.89X1 + 0.028X2 – 79.53), where Y is the score on the Apgar scale, X1 is the SрO2 in a pregnant woman, X2 is the STV. Conclusions. Assessment of the hypoxemia degree in pregnant women with COVID-19 infection and the cardiotocographic assessment of the fetus state require special attention: there is a direct association between these indicators and the assessment of the newborn according to the Apgar scale, which allows predicting the course of the period of early neonatal adaptation. It is recommended that these newborns be classified as a risk group with a violation of the adaptation period and possible long-term consequences. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Large-scale storage of 'green' hydrogen is essential in our quest to transition to renewable energy sources and achieve the net-zero emission targets. As such, Underground Hydrogen Storage (UHS) in geological porous media, such as in depleted oil and gas fields or saline aquifers, provides a cost-effective solution to store such large volumes of hydrogen (H 2) to buffer seasonal fluctuations in renewable energy supply and demand. Due to the novelty of the topic, many research gaps persist, but we focus on H 2 transport characteristics in the subsurface, hydrogen recoverability during cyclic operations, chemical interactions, and acoustic velocity as an indicator of H 2 saturation. In this study, we investigate UHS using a triaxial core-flooding experiment to address the above-mentioned research gaps by replicating field operations in the laboratory setup at representative subsurface conditions. Unstable displacement due to immiscible two-phase flow led to early H 2 breakthrough at 18% of H 2 saturation, ultimate H 2 saturation of 36% and withdrawal efficiency of 78% during the first cycle. However, cyclic charging and discharging led to an eventual H 2 withdrawal efficiency as high as 95%. Observed chemical interactions during our 3-day experiments were negligible, but our results also indicated a strong potential for evaporation-induced salt precipitation after injection of dry H 2 gas, leading to decreased reservoir porosity and permeability over time. Our ultrasonic measurements confirmed the sensitivity of P-wave velocity to H 2 saturation, which decreased by 3.5% when the H 2 saturation increased to 36%. This indicates that H 2 plume and leaks in UHS should be possible to monitor using 4D seismic surveys. Our results help to better understand H 2 flow, storage, and transport during cyclic UHS. The results indicate that H 2 withdrawal efficiency increases as the UHS reservoir matures and provides evidence of a dry near-well zone and evaporation induced salt precipitation in a UHS reservoir. [Display omitted] • Early breakthrough of H 2 at 18% H 2 saturation led to ultimate H 2 saturation of 36% after injecting 1.2 pore volumes of H 2. • H 2 withdrawal efficiency increased from 78% in the first cycle to 95% in the fourth cycle. • H 2 was produced at 90% purity with water vapor contamination indicating evaporation of liquid water into gaseous H 2. • 3.5% reduction in P-wave velocity when the H 2 saturation inside the specimen increased to 36%. • Evidence obtained for a dry near-well zone and evaporation induced salt precipitation during cyclic operations. [ABSTRACT FROM AUTHOR]

Forest biomass estimation is undoubtedly one of the most pressing research subjects at present. Combining multi-source remote sensing information can give full play to the advantages of different remote sensing technologies, providing more comprehensive and rich information for aboveground biomass (AGB) estimation research. Based on Landsat 8, Sentinel-2A, and ALOS2 PALSAR data, this paper takes the artificial coniferous forests in the Saihanba Forest of Hebei Province as the object of study, fully explores and establishes remote sensing factors and information related to forest structure, gives full play to the advantages of spectral signals in detecting the horizontal structure and multi-dimensional synthetic aperture radar (SAR) data in detecting the vertical structure, and combines environmental factors to carry out multivariate synergistic methods of estimating the AGB. This paper uses three variable selection methods (Pearson correlation coefficient, random forest significance, and the least absolute shrinkage and selection operator (LASSO)) to establish the variable sets, combining them with three typical non-parametric models to estimate AGB, namely, random forest (RF), support vector regression (SVR), and artificial neural network (ANN), to analyze the effect of forest structure on biomass estimation, explore the suitable AGB of artificial coniferous forests estimation of machine learning models, and develop the method of quantifying saturation value of the combined variables. The results show that the horizontal structure is more capable of explaining the AGB compared to the vertical structure information, and that combining the multi-structure information can improve the model results and the saturation value to a great extent. In this study, different sets of variables can produce relatively superior results in different models. The variable set selected using LASSO gives the best results in the SVR model, with an R 2 values of 0.9998 and 0.8792 for the training and the test set, respectively, and the highest saturation value obtained is 185.73 t/ha, which is beyond the range of the measured data. The problem of saturation in biomass estimation in boreal medium- and high-density forests was overcome to a certain extent, and the AGB of the Saihanba area was better estimated. [ABSTRACT FROM AUTHOR]

Vegetation classification has always been the focus of remote sensing applications, especially for tropical regions with fragmented terrain, cloudy and rainy climates, and dense vegetation. How to effectively classify vegetation in tropical regions by using multi-spectral remote sensing with high resolution and red-edge spectrum needs to be further verified. Based on the experiment in Wenchang, Hainan, China, which is located in the tropical monsoon region, and combined with the ZY-1 02D 2.5 m fused images in January, March, July, and August, this paper discusses whether NDVI and four red-edge vegetation indices (VIs), CIre, NDVIre, MCARI, and TCARI, can promote vegetation classification and reduce the saturation. The results show that the schemes with the highest classification accuracies in all phases are those in which the red-edge VIs are involved, which suggests that the red-edge VIs can effectively contribute to the classification of vegetation. The maximum accuracy of the single phase is 86%, and the combined accuracy of the four phases can be improved to 92%. It has also been found that CIre and NDVIre do not reach saturation as easily as NDVI and MCARI in July and August, and their ability to enhance the separability between different vegetation types is superior to that of TCARI. In general, red-edge VIs can effectively promote vegetation classification in tropical monsoon regions, and red-edge VIs, such as CIre and NDVIre, have an anti-saturation performance, which can slow down the confusion between different vegetation types due to saturation. [ABSTRACT FROM AUTHOR]

This paper experimentally investigates the influence of saturation on dynamic behaviors of concrete under both tension and compression stress states. Two grades of concrete were saturated to 0%, 50%, and 100% by oven drying and water soaking procedures. Split Hopkinson pressure bar (SHPB) tests, reaching the highest strain rate of about 170 s−1 , were carried out for dynamic compression. Dynamic splitting tensile tests were carried out by an Instron high-speed test machine, achieving the highest strain rate of about 40 s−1. The test results show that concrete specimens with different saturation ratios are all strain rate-sensitive. Under tensile loading, the effect of free on viscosity is only found to affect concrete's behavior when the strain rate is not very high. The strain rate sensitivity increases with water content when the strain rate is lower than about 3 s−1. However, when the strain rate is greater than 3 s−1 , strain rate sensitivity of concretes with different saturations become similar. Under compressive loading, free water in pores reduces the rate effect because it increases the hydrostatic pressure inside the specimen and leads to hydraulic fracturing. The microcracks caused by the hydraulic fracturing effect in the specimen result in macroscopic strength degeneration. [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]

Using the concept of methodological congruence—where the different elements of a study 'fit' together—we explore both problematic and good practice in (reflexive) thematic analysis (TA) as reported in Health Promotion International (HPI). Aligning with the importance we place on 'owning your perspectives' we situate this exploration in relation to our understanding of the variation in approaches to TA and qualitative research more broadly. This contextualization is necessary for highlighting why we judge practices to be in/congruent, and to facilitate more knowing congruence in future research. We critically reviewed a 'sample' of 31 papers published in HPI between 2010 and 2023 citing Braun and Clarke as reference for TA. We overview a range of problematic and good features of the use of TA in HPI , before focusing on two domains that seemed to present key challenges: theory and themes. Methodological incongruence can occur when postpositivist values and practices unwittingly creep into ostensibly non-positivist TA; we encourage thoughtfully and what we term 'knowing' consideration of theory, and quality practices and criteria. Methodological incongruence can also occur through mismatched conceptualizations of themes—notably, the use of 'topic summaries' as themes for reflexive TA (and fragmented thematic structures with 'thin' themes). We provide examples from the reviewed papers to demonstrate good practice in researcher reflexivity, articulation of theoretical and methodological frameworks and congruent themes. However, mindful of power dynamics, we only discuss problematic practice in general terms, to protect author anonymity. To facilitate thoughtful, quality TA—of all kinds—we provide eight pointers for researchers (and reviewers) to guide quality practice, and facilitate the use of concepts, procedures and criteria that promote knowing methodological congruence. [ABSTRACT FROM AUTHOR]

This paper studies the control problem for a continuous-time networked system with non-linearity in the state equation as well as in the input, as saturation. The system is considered under denial-of-service (DoS), attacks which cause the blockage of input and/or output components in the overall closed-loop model. An event-triggering scheme that is resilient in nature, along with an observer-based control, has been considered under DoS attacks. The resultant scheme ensures efficient network resources and excludes Zeno behavior naturally due to the presence of a minimum positive interevent delay. Then, an event-based switched non-linear model is presented to address both the event-triggering scheme and the presence of DoS blocking attacks. A piece-wise Lyapunov–Krasovskii functional method on the described non-linear model, resulting in the switched system, is considered for achieving an exponentially stable response by driving the required feasibility conditions. In the presence of a non-linear system with saturation in the actuator, the presented design establishes quantitative relationships among the exponential decay rate, active/sleeping intervals of attacks, parameters of the event-triggering condition, and sampling period of the system. After that, linear matrix inequalities are presented for designing an event-triggered controller with an observer, while the design also includes the region of convergence for dealing with the input non-linearity. Finally, comparative results for an offshore structure model with non-linearity in states as well as in actuator, are demonstrated to verify the results of the control scheme that is developed. It has been verified that our design is less conservative than the previous designs, and can handle the non-linearities in the dynamics of plant and actuator saturation more efficiently, while DoS attacks are also present. By applying our proposed method, the overshoot and undershoot are less than ±2.5 percent, while system states converge to the origin within 55 s. • An ϵ T-Lipschitz condition is used with a scaling factor ϵ and a variable matrix T • Non-linear control designed for system with input saturation and state non-linearity • Stability of the system is ensured in presence of DoS attacks with event triggering • Output feedback is utilized with switching non-linear observer having multiple gains • The joint design of all the required matrices using LK functions is utilized [ABSTRACT FROM AUTHOR]

The well called X (for confidential reasons) put into production in 2003 presents excessive water inflows a few years after it was put into production. The aim of this paper is to reduce this water flow through the chemical injection method. The available PVT, reservoir, and completion data are analyzed by using the nodal and sensitivity analysis methods. The results obtained show that initially the well X produced 509.1 STB/d of liquid, i.e. 71.3 STB/d of oil and 437.9 STB/d of water for a water cut of 86%. After flooding the tank with 80,000 ppm of polymers and 2,000 ppm of gels, the variation in viscosity followed by the decrease in oil saturation and the increase in water saturation will lead to a decrease in water cut (percentage of water production) up to 0%. This reduction in water cut is lighten the hydrostatic column so the liquid production rate is 2,572.5 STB/d of liquids, i.e. 2,058 STB/d of oil and 514.5 STB/d of water for a water cut of 20%. The economic report shows a minimum profit of $55,923,628 with a return on investment over a period of 1 month after the project is put into operation. [ABSTRACT FROM AUTHOR]

Natural gas hydrate is prospected as a new and promising, highly clean energy resource that mainly occurs in permafrost or at continental margins. Its formation is subject to many soil conditions, such as grain size, matrix materials, pore morphology, and permeability. In this study, we propose that grain size is the most decisive parameter that affects the saturation of gas hydrate in sediments based on data from Ocean Drilling Program Leg 164 and Mallik 5L-38, which represent marine sediments and terrestrial sediments, respectively. Our study reveals that high gas hydrate saturation generally occurs in coarse-grained sand, regardless of whether sediment formation is homogeneous or inhomogeneous, and the sorting of sediments may affect the hydrate saturation to a certain degree. Using grain size and sorting of sediments may be the most intuitive proxy method for a rough estimation of hydrate saturation. Further study is necessary to fully understand the relationship between hydrate morphology and sediment grain size, even though massive hydrates are typically found in fine clayey-rich sediments. [ABSTRACT FROM AUTHOR]

The paper considers a mathematical model of the filtration of two immiscible incompressible fluids in deformable porous media. This model is a generalization of the Musket–Leverett model, in which porosity is a function of the space coordinates. The model under study is based on the equations of conservation of mass of liquids and porous skeleton, Darcy's law for liquids, accounting for the motion of the porous skeleton, Laplace's formula for capillary pressure, and a Maxwell-type rheological equation for porosity and the equilibrium condition of the "system as a whole." In the thin layer approximation, the original problem is reduced to the successive determination of the porosity of the solid skeleton and its speed, and then the elliptic-parabolic system for the "reduced" pressure and saturation of the fluid phase is derived. In view of the degeneracy of equations on the solution, the solution is understood in a weak sense. The proofs of the results are carried out in four stages: regularization of the problem, proof of the maximum principle, construction of Galerkin approximations, and passage to the limit in terms of the regularization parameters based on the compensated compactness principle. [ABSTRACT FROM AUTHOR]

This study investigated the effects of color presence and saturation on the affective judgment of real-life images, as functions of the image's affective valence. In the first two experiments, participants observed and rated original color photos and their grayscale versions, presented in an interleaved order across two separate experimental sessions. Color photos were rated as more pleasant than grayscale photos when image valence was positive, and more unpleasant when image valence was negative. The third experiment consisted of the same original images and their versions with saturation reduced by 50%. Original photos were rated as more pleasant than saturation-reduced photos when image valence was positive, yet less unpleasant when image valence was negative, implying potentially separable mechanisms for processing color presence and saturation. Significant interactions were found between color or saturation mode and valence on affective judgment in all three experiments. The effects persisted after controlling for colorfulness and luminance between the color and grayscale (or de-saturated) conditions.