Stability Of Method Research Articles

Bound and resonance states of highly charged H‐ and He‐like ions under weakly coupled plasma environment

AbstractThe position of bound () states as well as doubly excited resonance , () states of symmetry has been determined for highly charged He‐like ions (, , , , , and Ar16+) along with their respective one‐electron thresholds (, , and ) under weakly coupled plasma environment. These particular ions and their respective charge states are selected due to their frequent occurrence in astrophysical and laboratory plasmas. Ritz variational method with multi‐exponent explicitly correlated Hylleraas type basis and pure‐exponential basis set are adopted for tackling He‐ and H‐like ions, respectively. The resonance width of a few low‐lying resonance states is determined using the stabilization method under different plasma conditions. Ionization potential depression is noted for both the bound and resonance states of the plasma‐embedded ions. It is evident that the width (or the lifetime) of the considered resonance states originating from different dominant configurations follows different patterns w.r.t. the plasma screening length.

Enhancing the Transferability of Adversarial Patch via Alternating Minimization

Adversarial patches, a type of adversarial example, pose serious security threats to deep neural networks (DNNs) by inducing erroneous outputs. Existing gradient stabilization methods aim to stabilize the optimization direction of adversarial examples through accumulating gradient momentum to enhance attack transferability on black-box models. However, they are not fully effective for adversarial patches. The accumulated momentum during optimization often misaligns with the optimization direction, reducing their efficacy in black-box scenarios. We introduce an optimization method called Alternating Minimization for Adversarial Patch (AMAP). This method decomposes the original AP into multiple sub-patches and utilizes their update direction to stabilize the optimization of the original AP. Additionally, we propose an adaptive step size optimization method that accelerates convergence and boosts the attack performance. In face recognition tasks, AMAP outperforms baseline methods by a remarkable 5.21% and exceeds the second-best method by 1.4%. Furthermore, AMAP demonstrates practical feasibility in the physical domain, highlighting its potential for robust computer security testing applications.

Nicholson’s blowflies differential equations with a small delay in the mortality term

For the Nicholson’s blowflies equation with delayed mortality N′(t)=m(t)−δN(h1(t))+PN(h2(t))e−γN(h2(t)),P>δ,positivity, persistence, and boundedness of solutions are established. Two global stability tests for the positive equilibrium are obtained based on a linearized global stability method, reducing stability of a non-linear model to a specially constructed linear equation. The first one extends the absolute stability result to the case of delayed mortality and the second test is delay-dependent.

P-glycoprotein-mediated herb-drug interaction evaluation between Tenacissoside G and paclitaxel.

P-glycoprotein (P-gp)-mediated herb-drug interactions (HDIs) may impact drug efficacy and safety. Tenacissoside G (Tsd-G), a major active component of Marsdenia tenacissima, exhibits anticancer activity. To analyze the effect of Tsd-G on the pharmacokinetics of paclitaxel (PTX), researchers selected 30 Sprague-Dawley (SD) rats, randomized into a solvent control group, a verapamil positive control group, and 20, 40, and 60 mg/kg Tsd-G groups. After seven consecutive days of intraperitoneal injection of verapamil or Tsd-G, a single dose of 6 mg/kg PTX was injected intravenously. Plasma samples were collected at different time points, and proteins were precipitated using a methanol-acetonitrile solution. An ultrahigh-performance liquid chromatography-tandem mass spectrometry method was developed, with docetaxel as an internal standard, and quantified using positive ion multiple reaction monitoring (MRM) mode. This analytical method's specificity, accuracy, precision, recovery, matrix effect, and sample stability meet the requirements for biological sample determination. After Tsd-G administration in rats, the mean residence time of PTX was significantly prolonged. And Tsd-G can stably bind to P-gp by forming hydrogen bonds and inhibiting the expression of P-gp in rat liver. Although the metabolites of PTX were not detected in this study, the above results still indicate the existence of HDIs between Tsd-G and PTX, and P-gp may be the main target to mediate HDIs.

Cross‐correlating soil aggregate stability methods to facilitate universal interpretation

Cross‐correlating soil aggregate stability methods to facilitate universal interpretation

Establishing validated RT-qPCR workflow for the analysis of oligodendrocyte gene expression in the developing murine brain.

Myelination is essential for the proper conduction of impulses across neuronal networks. Mature, myelinating glia differentiate from progenitor cells through distinct stages that correspond to oligodendrocyte-specific gene expression markers. Reverse transcription quantiatative PCR (RT-qPCR) is a common technique used to quantify gene expression across cell development; however, a lack of standardization and transparency in methodology may lead to irreproducible data. Here, we have designed and validated RT-qPCR assays for oligodendrocyte genes and reference genes in the developing C57BL6/J mouse brain that align with the MIQE guidelines, including quality controls for primer specificity, temperature dependence, and efficiency. A panel of eight commonly used reference genes was ranked using a series of reference gene stability methods that consistently identified Gapdh, Sdha, Hmbs, Hprt1, and Pgk1 as the top candidates for normalization across brain regions. In the cerebrum, myelin genes peaked in expression at postnatal day 21, which corresponds to the peak of developmental myelination. The gene expression patterns from the brain homogenate were in agreement with previously reported RNA-seq and microarray profiles from oligodendrocyte lineage cells. The validated RT-qPCR assays begin to build a framework for future investigation into the molecular mechanisms that regulate myelination in mouse models of brain development, aging, and disease.

Increasing numerical stability of mountain valley glacier simulations: implementation and testing of free-surface stabilization in Elmer/Ice

Abstract. This paper concerns a numerical stabilization method for free-surface ice flow called the free-surface stabilization algorithm (FSSA). In the current study, the FSSA is implemented into the numerical ice-flow software Elmer/Ice and tested on synthetic two-dimensional (2D) glaciers, as well as on the real-world glacier of Midtre Lovénbreen, Svalbard. For the synthetic 2D cases it is found that the FSSA method increases the largest stable time-step size at least by a factor of 5 for the case of a gently sloping ice surface (∼ 3°) and by at least a factor of 2 for cases of moderately to steeply inclined surfaces (∼ 6° to 12°) on a fine mesh. Compared with other means of stabilization, the FSSA is the only one in this study that increases largest stable time-step sizes when used alone. Furthermore, the FSSA method increases the overall accuracy for all surface slopes. The largest stable time-step size is found to be smallest for the case of a low sloping surface, despite having overall smaller velocities. For an Arctic-type glacier, Midtre Lovénbreen, the FSSA method doubles the largest stable time-step size; however, the accuracy is in this case slightly lowered in the deeper parts of the glacier, while it increases near edges. The implication is that the non-FSSA method might be more accurate at predicting glacier thinning, while the FSSA method is more suitable for predicting future glacier extent. A possible application of the larger time-step sizes allowed for by the FSSA is for spin-up simulations, where relatively fast-changing climate data can be incorporated on short timescales, while the slow-changing velocity field is updated over larger timescales.

Cinnamon Particle‐Stabilized Gas Marbles: A Novel Approach for Enhanced Stability and Versatile Applications

AbstractSuspension of solid particles at interfaces is a common phenomenon, pivotal in natural, and industrial contexts. This study focuses on gas marbles which are single soap‐like air bubbles in air environment stabilized by colloidal particles. A unique stabilization method employing edible cinnamon particles is introduced. Unlike previous studies using spherical particles, the irregularly‐shaped micrometer‐sized cinnamon particles demonstrate remarkable long‐term stability through jamming and interlocking at the air‐liquid interface. Comprehensive characterization via optical and scanning electron microscopy, and contact angle experiments, elucidates the stabilization mechanism. These gas marbles exhibit exceptional resilience against drying, heating, freezing, and mechanical stress. They can be fabricated with various edible liquids offering extensive customization possibilities. This breakthrough introduces a promising method for creating stable gas marbles with edible particles, offering versatility for various fields and applications. The application scope includes surface catalysis and shock/vibration sensors, and also molecular gastronomy.

Analysis of Caputo Sequential Fractional Differential Equations with Generalized Riemann–Liouville Boundary Conditions

This paper delves into a novel category of nonlocal boundary value problems concerning nonlinear sequential fractional differential equations, coupled with a unique form of generalized Riemann–Liouville fractional differential integral boundary conditions. For single-valued maps, we employ a transformation technique to convert the provided system into an equivalent fixed-point problem, which we then address using standard fixed-point theorems. Following this, we evaluate the stability of these solutions utilizing the Ulam–Hyres stability method. To elucidate the derived findings, we present constructed examples.

Aperiodic small signal stability method for detection and mitigation of cascading failures in smart grids

The occurrence of cascading failures poses significant risks to the stability and reliability of modern smart grids. This article presents a novel hybrid algorithm designed to assess and mitigate these failures. The technique combines advanced clustering algorithms, specifically Affinity Propagation Graph (APG) and Self-Propagating Graph (SPG), to detect critical nodes, and Unified Power Flow Controllers (UPFCs) to provide compensation to grid networks. The algorithm first uses APG to divide the network into clusters and considers the center bus as the critical node. If the center bus is not critical, SPG is applied to identify the critical node. This hybrid approach identifies the critical node in just 0.02 s (for both APG and SPG) and with improved accuracy compared to existing methods. After identifying critical nodes, UPFCs are strategically installed to regulate power flow and reduce the probability of cascading failures, with compensation taking approximately 0.14 s. Simulation results demonstrate the effectiveness of the proposed method in enhancing grid resilience and reducing the likelihood of cascading failures. By strategically deploying UPFCs at critical nodes, this approach ensures resilient grid operation in various scenarios. This research significantly contributes to the development of smart grid technologies by providing a comprehensive framework to address cascading failures in power distribution networks. The proposed method shows potential for improving the reliability and stability of power grids amid changing system dynamics and uncertainties.

Contrastive-Active Transfer Learning-Based Real-Time Adaptive Assessment Method for Power System Transient Stability.

The transient stability assessment based on machine learning faces challenges such as sample data imbalance and poor generalization. To address these problems, this paper proposes an intelligent enhancement method for real-time adaptive assessment of transient stability. In the offline phase, a convolutional neural network (CNN) is used as the base classifier. A model training method based on contrastive learning is introduced, aiming to increase the spatial distance between positive and negative samples in the mapping space. This approach effectively improves the accuracy of the model in recognizing unbalanced samples. In the online phase, when real data with different distribution characteristics from the offline data are encountered, an active transfer strategy is employed to update the model. New system samples are obtained through instance transfer from the original system, and an active sampling strategy considering uncertainty is designed to continuously select high-value samples from the new system for labeling. The model parameters are then updated by fine-tuning. This approach drastically reduces the cost of updating while improving the model's adaptability. Experiments on the IEEE39-node system verify the effectiveness of the proposed method.

Post-treatment Functional Outcomes of Distal Tibiofibular Syndesmosis Injuries With Varying Duration and Method of Stabilization

The purpose of this study was to assess whether the type and duration of screw fixation affects ankle joint functional scores and patient activity levels. We evaluated 55 patients who had undergone surgical treatment for ankle fracture with concomitant distal tibiofibular syndesmosis injury. The follow-up period ranged from 2 years to 4 years and 2 months (mean 36 months). Depending on the time of screw removal, patients were divided into 2 groups (the 8–15-week group-19 patients, and the 16–22-week group-36 patients). There were 17 patients with tricortical and 38 patients with quadricortical syndesmosis fixation. The following parameters were assessed: range of motion, rates of complications, level of pain in visual analogue scale (VAS), and function. In the quadricortical fixation group the range of plantar flexion p = .04 and adduction p = .043 were significantly lower in the operated than in the nonoperated limb. In the patients who had their syndesmotic screws removed after 16–22 weeks, the range of plantar flexion in the operated limb was significantly lower than that in the nonoperated limb. We observed no differences between the evaluated groups in terms of ankle joint mobility, VAS pain levels, functional outcomes, or complication rates. All the analyzed subgroups showed poorer ranges of some types of motion in the ankle and worse functional scale and VAS pain scores after treatment in comparison with those before the injury. We suggest removing the syndesmotic screws after 8–15 weeks, due to the possibility of earlier rehabilitation, faster return to work and physical activity and less burden on the health care system. Tricortical or quadricortical syndesmosis fixation is at the surgeon's discretion.

Orbital stability of multi-peakons for a generalized Dullin–Gottwald–Holm equation

In this paper, we consider a generalized Dullin–Gottwald–Holm equation. The equation admits single peakons and multi-peakons. Using energy argument and combining the method of the orbital stability of a single peakon with monotonicity of the local energy norm, we prove that the sum of N sufficiently decoupled peakons is orbitally stable in the energy space.

A Reduced-Order Impedance Model and Analytical Loop-Correction Stabilization Method for Electric Vehicle DC Charging Station

A Reduced-Order Impedance Model and Analytical Loop-Correction Stabilization Method for Electric Vehicle DC Charging Station

Study on the stability and ultra-low frequency oscillation suppression method of pumped storage power plant with dual units sharing one pipeline

This paper aims to investigate the stability of the pumped storage power plant (PSPP) with dual units sharing one pipeline (DUSOP) and the method of suppressing the ultra-low frequency oscillation (ULFO) characteristics. Firstly, four nonlinear models of pumped storage regulation system (PSRS) with DUSOP are established under the design scenarios of no surge tank, upstream surge tank (UST), downstream surge tank, and upstream and downstream dual surge tanks. Then the stability of the PSRS under different surge tank arrangements (STAs) in the long diversion system design scenarios (LDSDS) is comparatively analyzed. Finally, based on the concept of stability margin, the influence mechanism of the operating points on the ULFO characteristics is investigated in the LDSDS with UST, and the influence of the governor parameters, hydrodynamic parameters, and mechanical parameters on the damping ratio and frequency of the system is also analyzed. The results show that among STAs, the design scheme of arranging the UST is more reasonable for PSPP with LDSDS from the comprehensive consideration of the economy of the project and the stability of the system. For PSPP with UST, on the line of equal stability margin, increasing the proportional gain, reducing the unit inertia time constant, reducing the water flow inertia time constant, and appropriately increasing the area of the surge tank can increase the frequency and reduce the amplitude, which is conducive to the suppression of ULFO. In the stability domain range, increasing the proportional gain increases the frequency and the system stability increases and then decreases. Increasing the integral gain decreases the frequency and then increases the system stability. At the same time, the frequency of the unit can be changed by adjusting the parameters of the system to avoid resonance between the frequency of the unit and the frequency of the power grid and to ensure the stability and safety of the unit operation.

Innovations in Treatment of Femoral Fractures Throughout History

Treatment for femoral shaft fractures throughout history was a particularly challenging problem with poor outcomes until recent times. Injury to the femur bone prior to reliable methods of stabilization and fixation meant nearly certain death or profound disability for the rest of the patient’s days. Physicians and surgeons over time devised various mechanisms for splinting, stabilizing and providing traction for nonoperative treatment. Eventually, surgical treatment became a safe and reliable method for addressing these injuries. Advancements in treatment for femur fractures was tackled by some of the great physicians throughout history, including Hippocrates and Galen. The purpose of this manuscript is to provide an overview of the major milestones in care for femur fractures throughout the course of human history.

Investigation of Concentration Stabilization Methods for Hydrogen-Blended Natural Gas Grid Based on Gas Supply Routes

Investigation of Concentration Stabilization Methods for Hydrogen-Blended Natural Gas Grid Based on Gas Supply Routes

Pharmacological properties and stability of natural–colored foods: a literature review

Purpose Natural food colors used in food are generally perceived as additives. Therefore, many studies have been conducted to prove the health benefits and risks of using natural food colors, which play an important role in the food industry, and to identify realistic stabilization methods. This paper aims to examine the health effects of natural food colors from a pharmacological approach. Design/methodology/approach The paper searches for relevant literature using keywords such as “natural food coloring”, “stabilization” and “antioxidant effects”. For the case study area, this paper added “food science and technology” to identify methods for stabilizing natural food coloring. From this review, the authors ultimately selected 79 articles that appeared to meet the research objectives. Findings When using natural food coloring in food, there are concerns about stabilization. However, with the development of food science and technology, the authors have found that there are multi-layer emulsification methods that can be applied before, during and after food manufacturing, and storage standards are also important. Natural food coloring is playing a diverse role in food science. Originality/value Natural food coloring has been reported in various types of literature to have antioxidant, anti-inflammatory and antitumor effects. The most common pigments are carotenoids. Considering the positive effects of natural food coloring on human health, the authors suggest future directions for the development of food science and technology and provide a perspective for changing consumer perceptions.

Operationally stable perovskite solar modules enabled by vapor-phase fluoride treatment.

The ever-increasing power conversion efficiency of perovskite solar cells has illuminated the future of the photovoltaic industry, but the development of commercial devices is hampered by their poor stability. In this study, we report a scalable stabilization method using vapor-phase fluoride treatment, which achieves 18.1%-efficient solar modules (228 square centimeters) with accelerated aging-projected T80 lifetimes (time to 80% of efficiency remaining) of 43,000 ± 9000 hours under 1-sun illumination at 30°C. The high stability results from vapor-enabled homogeneous fluorine passivation over large-area perovskite surfaces, suppressing defect formation energy and ion diffusion. The extracted degradation activation energy of 0.61 electron volts for solar modules is comparable to that of most reported stable cells, which indicates that modules are not inherently less stable than cells and closes the cell-to-module stability gap.

Implementation of a slope stability method in the CRITERIA-1D agro-hydrological modeling scheme

AbstractThis paper presents the implementation of a slope stability method for rainfall-induced shallow landslides in CRITERIA-1D, which is an agro-hydrological model based on Richards’ equation for transient infiltration and redistribution processes. CRITERIA-1D can simulate the presence and development of roots and canopies over space and time, the regulation of transpiration activity based on real meteorological data, and the evaporation reduction caused by canopies. The slope can be considered composed of a multi-layered soil, leading to the possibility of simulating the bedrock and of setting an initial water table level. CRITERIA-1D can consider different soil horizons characterized by different hydraulic conductivities and soil water retention curves, thus allowing the simulation of capillarity barriers. The validation of the proposed physically based slope stability model was conducted through the simulation of the collected water content and water potential data of an experimental slope. The monitored slope is located close to Montuè, in the north-eastern sector of Oltrepò Pavese (northern Apennines—Italy). Just close to the monitoring station, a shallow landslide occurred in 2014 at a depth of around 100 cm. The results show the utility of agro-hydrological modeling schemes in modeling the antecedent soil moisture condition and in reducing the overestimation of landslides events detection, which is an issue for early warning systems and slope management related to rainfall-induced shallow landslides. The presented model can be used also to test different bioengineering solutions for slope stabilization, especially when data about rooting systems and plant physiology are known.