Initial Energy Level Research Articles

ESTIMATION OF ND:YAG LASER ENERGY FOR VARIOUS TYPES OF POSTERIOR CAPSULE OPACITY

Abstract
 Introduction & Objectives : Types of Posterior capsule opacity (PCO) are membranous, fibrotic, or fibro-membranous. Surgical capsulotomy has been replaced by Neodymium-doped Ytrium Aluminim Garnet (Nd:YAG) as a PCO management nowdays. The initial energy use of the laser is influenced by variations in PCO density. Utilizing initial energy effectively can help to use less total laser energy. This study is to estimate energy Nd:YAG laser levels to treat various types of PCO.
 Methods : This is a observational descriptive study with cross-sectional design. This study retrieved initial and total capsulotomy Nd:YAG laser as a main variable on various types of PCO. The best corrected visual acuity (BCVA) before and after laser, size of hole capsulotomy, and complications of each type of PCO were evaluated.
 Results : A total 59 eyes of 49 patients with pseudophakia who underwent capsulotomy laser were included. The mean values of initial energy levels were 1,45±0,31 mJ for membranous PCO, 1,51±0,29 mJ for fibrous PCO, and 1,68±0,23 mJ for fibro-membran PCO. The mean summated energy levels for membranous PCO was 51,86±28,19 mJ, 78,86±44,81 mJ for fibrous PCO, 86,88±60,51 mJ for fibro- membran PCO. Complications were iritis, oculi hypertension, hyaloid rupture and IOL pitting were occurred in this study.
 Conclusion : Fibro-membran PCO required more initial and total laser energy compared to membranous and fibrous PCO

A Statistical Analysis of Wireless Body Area Network using Clustering Based Routing Protocols

Recently, research on wireless body-area sensor networks (WBASN) or wireless body area networks (WBANs) has gained great importance in medical applications, and now plays an important role in patient monitoring. Clustering is the most important task in wireless sensor networks (WSNs) by data aggregation through each cluster head (CH). The development of technology has seen comfort in the domestic and professional life of an individual. However, such survival was not able to meet medical emergencies during the pandemic COVID-19 and other health surveillance scenarios. As a result, it is important to design an energy-efficient routing system for WBAN. Existing routing algorithms focus more on energy efficiency than security. A Secure Optimal Path-Routing (SOPR) protocol is proposed to identify and discover routes in WBAN that are secure against black-hole attacks. In this paper the sensor's wireless capability has been tested with a simulator to detect and transmit signals across a wide range of frequencies and to ensure that data is transferred successfully. CARF reduces the maximum work done by relay nodes in case of overloaded nodes and thereby increases the energy distribution in the network. The proposed CARF design reduces packet loss and time delay, thereby increasing network lifetime compared to other fuzzy and heuristic methods used for routing in WSNs. The proposed algorithm maintains more than 75% of the residual energy in the network at a minimum initial energy level of 1 J to enable data syncing. A SAC-TA approach for data aggregation in WSNs is presented. False injection attacks are identified based on traffic analysis at the time of the route discovery process. One-time key generation algorithm is introduced to eliminate malicious nodes from the network. The presented paper proposes a congestion-free routing framework for data transmission from source to sink nodes in WSNs. Congestion-aware routing mechanisms modeled using fuzzy sets (CARF) include operations such as establishing non-localized nodes, by which more paths can be created for traffic distribution, and predicting an optimal congestion.

Global well-posedness of solutions for 2-D Klein–Gordon equations with exponential nonlinearity

This paper considers the global well-posedness of two-dimensional Klein–Gordon equations with exponential nonlinearity. By employing the potential well method, we conduct a comprehensive study on the global existence and finite time blowup of solutions by the requirement of the initial energy at three different initial energy levels.

Energy deficit in surgery on the examples of cholestasis and massive liver resection

The paper is dedicated to the energy processes associated with diseases in living organisms. Experiments involved 151 rats. Liver tissue was taken to determine its energy state in cholestasis (common bile duct ligation) and after resection of 60% and 80% of the parenchyma (without cholestasis). Adenine nucleotides (ATP, ADP, and AMP) and activity of gluconeogenesis enzymes were studied in cholestasis every 3 days for 15 days and after liver resection – every 6 hours for 3 days. Particular attention was paid to the energy deficit in liver tissue. A certain level of energy deficit n agent of metabolic stress. The experiments revealed that the energy deficit in the liver tissue increased by 15% by day 6 of cholestasis and by 48–50% of the initial energy level by days 12–15. The increase in energy deficit in liver tissue inversely correlated with the decrease in the activity of gluconeogenesis enzymes – by day 15 glucose-6- phosphate dehydrogenase reduced by 44% and isocitrate dehydrogenase – by 48% of the initial energy level. Decompression after 15 days from the onset of cholestasis was followed by an increase in energy deficit by 15%, as compared to the initial energy level, within 3–5 days. No development of metabolic stress was evidenced by a decrease in the activity of gluconeogenesis enzymes. After 12 hours after resection of 60% and 80% of the liver parenchyma, the liver energy deficit in both groups accounted for 50% of the initial energy level. After resection of 60% of the liver parenchyma, the energy deficit decreased rapidly: after 24 hours to 30%, after 72 hours to 11%; 2 rats out of 30 died during this period. After 12 hours after resection of 80% of the liver parenchyma, the energy deficit rose sharply: after 24 hours to 70% of the initial energy level. This led to the death of 26 animals out of 31. Both groups of animals demonstrated an inverse relationship between the decreased amount of energy used for hepatocyte function and the increased activity of key enzymes of gluconeogenesis. The obtained results suggest that in both groups of animals, metabolic stress developed after liver resection, however, after resection of 80% of the organ parenchyma, it “choked” due to the deficit of remnant hepatocytes. Most of the energy was spent for the development of regeneration. Metabolic stress and regeneration develop simultaneously. A deficit of 50% of energy in liver tissue with a further increase may indicate a critical condition, both in cholestasis and after a massive resection. The research into energy changes in cholestasis and after massive liver resections reveals new patterns of internal processes of the body.

Blow-up phenomena for a singular nonlocal viscoelastic problem with logarithmic nonlinearity

This article deals with the blow-up phenomena for a singular nonlocal viscoelastic equation with logarithmic nonlinearity subject to nonlocal boundary conditions u(α,t)=0 and ∫0αxu(x,t)dx=0. Under the three different initial energy levels, we established the finite time blow-up criterion, and then give the upper bounds for blow-up time T∗ depending on the sign and range of initial energy E(0).

On the post-impact fatigue behavior and theoretical life prediction of CF/PEEK-titanium hybrid laminates using an energy dissipation approach

This paper aims to illustrate the effect of the impact damage on fatigue behavior of CF/PEEK-titanium hybrid laminates. To achieve this end, a fatigue life model was proposed to predict the S–N curves of the laminates at various initial impact energy levels and stress ratios based on the energy dissipation approach. The energy dissipation behavior of the laminates during fatigue loading under different experimental conditions was analyzed through a large amount of post-impact fatigue tests, and the correlation between the initial impact damage and the total fatigue dissipation energy was determined. The full-field axial strain distribution of the titanium layer on the impacted side of the laminate was characterized in terms of initial impact energy level and maximum stress using digital image correlation, and then the post-impact fatigue failure mechanism of CF/PEEK-Ti hybrid laminates was summarized. Finally, the validity of the proposed model was verified by fatigue tests under other conditions of stress ratio and impact energy level. It is worth mentioning that the proposed model is also applicable to other types of FMLs, and can accurately predict the residual fatigue life of laminates after impact with only one set of S–N curve data.

Research of Islanding Operation and Fault Recovery Strategies of Distribution Network Considering Uncertainty of New Energy

With the problems of fault handling in the distribution network, few studies concern the correlation between islanding operation and fault recovery. Thus, this paper proposes an islanding operation and fault recovery strategy for the distribution network considering the uncertainty of new energy. Firstly, the objectives of the distribution network islanding division scheme and operation optimization are established. Combined with distribution network radiation constraints, islanding power supply capacity, safety constraints, and distributed generator (DG) operation constraints, a rolling optimization method is used to construct the distribution network islanding division and operation model. Secondly, in the fault recovery stage, considering the characteristics of the island operation stage, a node load weight value is designed. A distribution network fault recovery model is then constructed with the goals of ensuring greater load power supply recovery, improving electricity satisfaction, and reducing network losses and switching times. Thirdly, considering the randomness of intermittent DGs such as wind power and photovoltaics, an uncertainty model of intermittent DGs is constructed. A solution method for the distribution network islanding operation and fault recovery model considering uncertainty is proposed by combining scenario generation reduction methods and second-order cone programming theory. Finally, the proposed method’s feasibility and effectiveness are verified using the improved IEEE 33-node distribution network. The results show that in the islanding division stage, the node voltage consistently remains between 1.08 pu and 1.1 pu when new energy achieves up to 34.09% and 48.65%, and the line losses represent approximately 0.22% to 0.26% of the total load when the initial energy levels of the storage are at 50% and 80%. In the fault recovery stage, compared to the method without network reconstruction, the system shows significant power loss reductions of approximately 11.9%, 13.6%, and 14.2% in three respective cases.

Brighten strontium aluminate long-persistence materials via optimizing defect energy level distribution

Afterglow brightness of inorganic persistent luminescent (PersL) materials upon ceasing light excitation represents an important parameter for various glow-in-the-dark applications. Although the emission wavelength of PersL materials is developed to cover over the whole spectral range from ultraviolet to near infrared light, and light emission is sufficiently long-lasting with a fractional number of rare-earth doped PersL materials commercially available, PersL materials with high initial afterglow brightness at room-temperature condition remain rarely reported. Employing trap-controlled temperature dependency of persistent luminescence mechanism, defect energy level distribution, and microwave-assisted solid-state reaction, here a highly bright green-emitting strontium aluminate phosphor is reported. Higher initial afterglow brightness (a photometric luminance of 99.8 cd/m2, enhanced 1.7 times than that of the commercial one) is achieved due to the massive aggregation of charge carriers at shallow-trap energy levels. The relation between initial afterglow brightness and trap energy level distribution is investigated. The glowing-in-the-dark composite panel composed of Sr4Al14O25:Eu2+, Dy3+ and Polydimethylsiloxane can light up the safety sign and the map of fire evacuation route. These findings may provide a major step forward to developing high-brightness PersL materials and are expected to further benefit a wide range of PersL material systems for practical glow-in-the-dark applications.

Semiclassical Multistate Dynamics for Six Coupled 5A' States of O + O2.

Dynamics simulations of high-energy O2-O collisions play an important role in simulating thermal energy content and heat flux in flows around hypersonic vehicles. To carry out such dynamics simulations efficiently requires accurate global potential energy surfaces and (in most algorithms) state couplings for many energetically accessible electronic states. The ability to treat collisions involving many coupled electronic states has been a challenge for decades. Very recently, a new diabatization method, the parametrically managed diabatization by deep neural network (PM-DDNN), has been developed. The PM-DDNN method uses a deep neural network architecture with an activation function parametrically dependent on input data to discover and fit the diabatic potential energy matrix (DPEM) as a function of geometry, and the adiabatic potential energy surfaces are obtained by diagonalization of a small matrix with analytic matrix elements. Here, we applied the PM-DDNN method to the six lowest-energy potential energy surfaces in the 5A' manifold of O3 to perform simultaneous diabatization and fitting; the data are obtained by extended multistate complete-active-space second-order perturbation theory. We then used the adiabatic surfaces for dynamics calculations with three methods: coherent switching with decay of mixing (CSDM), curvature-driven CSDM (κCSDM), and electronically curvature-driven CSDM (eκCSDM). The κCSDM calculations require only adiabatic potential energies and gradients. The three dynamical methods are in good agreement. We then calculated electronically nonadiabatic, electronically inelastic, and dissociative cross sections for seven initial collision energies, five initial vibrational levels, and four initial rotational levels. Trends in the electronically inelastic cross sections as functions of the initial collision energy and vibrational level were rationalized in terms of the coordinate ranges where the gaps between the second and third potential energy surfaces are small.

Improved growth estimate of infinite time blowup solution for a semilinear hyperbolic equation with logarithmic nonlinearity

In this short paper, we give an improved estimate of the infinite time blowup solution for the semilinear wave equation with logarithmic nonlinearity. Comparing the previous work, this improved growth estimate not only provides the information about the relationship between the power of the nonlinearity and the growth, but also gives a faster growth estimate. The proof of the main conclusions is carried out at the negative initial energy level, the sub-critical initial energy level, the critical initial energy level and the arbitrary positive initial energy level.

Global dynamical behavior of solutions for finite degenerate fourth-order parabolic equations with mean curvature nonlinearity

<abstract><p>In this work, the initial-boundary value problem for the global dynamical properties of solutions to a class of finite degenerate fourth-order parabolic equations with mean curvature nonlinearity is studied. With the help of the Nehari flow and Levine's concavity method, we establish some sharp-like threshold classifications of the initial data under sub-critical, critical and supercritical initial energy levels, that is, we describe the size of an initial data set. It requires the presumption that the initial data starting from one region of phase space have uniform global dynamical behavior, which means that the solution exists globally and decays via energy estimates that ultimately result in the solution tending to zero in the forward time. For the case in which the initial data corresponds to another region, we prove that the solutions related to these initial data are subject to blow-up phenomena in a finite time. In addition, we estimate the corresponding upper bound of the lifespan of the blow-up solution.</p></abstract>

Blowup phenomena for a fourth order wave equation at high initial energy level

Blowup phenomena for a fourth order wave equation at high initial energy level

Discharge Characteristics and System Performance of the Ablative Pulsed Plasma Thruster with Different Structural Parameters

Under the given initial discharge energy level, altering the electrode structural parameters of the Ablative Pulse Plasma Thruster (APPT) is an effective way to improve the performance of the thruster. The purpose of this study is to reveal the underlying mechanism of the effect of changing the electrode structure parameters on the performance of the APPT system and to offer targeted support for researchers to optimize the design of APPT structure. With rectangular and tongue-shaped electrode configurations at various electrode flare angles, electrode lengths, and electrode spacings, the discharge characteristics, propellant ablation characteristics, and thruster performance of the APPT are systematically investigated. The underlying mechanism of how changing the electrode’s configuration parameter affects the performance of the thruster is identified by fitting and predicting the parameters of the APPT discharge circuit and system performance under various operating conditions. The results show that using tongue-shaped electrodes is more effective than using rectangular electrodes in terms of enhancing the inductive gradient of the electrodes, transferring more energy to the discharge channel, and increasing the squared integral value of the discharge current. As a result, the tongue-shaped electrode APPT performs better than the APPT with rectangular electrodes, as a consequence. The thruster’s performance can be enhanced for the same electrode configuration by increasing the electrode flare angle within a certain angle range; however, the improvement is extremely limited. Additionally, in the case of small electrode spacing, increasing the electrode flare angle can enhance the thruster’s performance more effectively.

Modulated relay based stable election protocol for large‐scale wireless sensor networks

SummaryInternet of things (IoT) applications based on wireless sensor networks (WSNs) have recently gained vast momentum. These applications vary from health care, smart cities, and military applications to environmental monitoring and disaster prevention. As a result, energy consumption and network lifetime have become the most critical research area of WSNs. Through energy‐efficient routing protocols, it is possible to reduce energy consumption and extend the network lifetime for WSNs. Using hybrid routing protocols that incorporate multiple transmission methods is an effective way to improve network performance. This paper proposes modulated R‐SEP (MR‐SEP) for large‐scale WSN‐based IoT applications. MR‐SEP is based on the well‐known stable election protocol (SEP). MR‐SEP defines three initial energy levels for the nodes to improve the network energy distribution and establishes multi‐hop communication between the cluster heads (CHs) and the base station (BS) through relay nodes (RNs) to reduce the energy consumption of the nodes to reach the BS. In addition, MR‐SEP reduces the replacement frequency of CHs, which helps increase network lifetime and decrease power consumption. Simulation results show that MR‐SEP outperforms SEP, LEACH, and DEEC protocols by 70.2%, 71.58%, and 74.3%, respectively, in terms of lifetime and by 86.53%, 86.68%, and 86.93% in terms of throughput.

Global well-posedness analysis for the nonlinear extensible beam equations in a class of modified Woinowsky-Krieger models

Abstract For studying the evolution of the transverse deflection of an extensible beam derived from the connection mechanics, we investigate the initial boundary value problem of nonlinear extensible beam equation with linear strong damping term, nonlinear weak damping term, and nonlinear source term. The key idea of our analysis is to describe the invariant manifold via Nehari manifold. To establish the results of global well-posedness of solution, we consider the problem at three different initial energy levels, i.e., subcritical initial energy level, critical initial energy level, and arbitrarily high initial energy level. We first obtain the local existence of the solution by using the contraction mapping principle. Then, in the framework of potential well, we obtain global existence, nonexistence, and asymptotic behavior of solution for both subcritical initial energy level and critical initial energy level. In the end, we establish the global nonexistence of solution for the problem with linear weak damping and strong damping at the arbitrarily high initial energy level.

EXPONENTIAL GROWTH OF SOLUTIONS FOR A VARIABLE-EXPONENT FOURTH-ORDER VISCOELASTIC EQUATION WITH NONLINEAR BOUNDARY FEEDBACK

In this paper we study a variable-exponent fourth-order viscoelastic equation of the form$$|u_{t}|^{\rho(x)}u_{tt}+\Delta[(a+b|\Delta u|^{m(x)-2})\Delta u]-\int_{0}^{t}g(t-s)\Delta^{2}u(s)ds=|u|^{p(x)-2}u,$$in a bounded domain of $R^{n}$. Under suitable conditions on variable exponents and initial data, we prove that the solutions will grow up as an exponential function with positive initial energy level. Our result improves and extends many earlier results in the literature such as the on by Mahdi and Hakem (Ser. Math. Inform. 2020, https://doi.org/10.22190/FUMI2003647M).

Global well-posedness of fourth-order Petrovsky equation with weak and strong damping terms

In this paper, a semilinear fourth-order Petrovsky equation with nonlinear weak damping term and linear strong damping term is considered in the frame of the potential well. We prove the existence and uniqueness of the global strong solution with sub-critical initial energy. In addition, we obtain the global existence, asymptotic behaviour and finite time blowup for the weak (non-steady state) solution with a critical initial energy level.

Effects of fuel conversion ratio on cooling and drag reduction performance for supersonic film using gaseous hydrocarbon fuel

Film cooling especially combined with regenerative cooling is an effective solution to meet the heat protection and the drag reduction demands for hydrocarbon-fueled scramjet engines. Typically, fuel is the only available coolant to organize the active cooling for hypersonic vehicles, and the coolant used in the film cooling is extracted from the regenerative cooling channels; however, the fuel pre-cracking in the regenerative cooling process must be considered as it can change the initial composition and energy level of the coolant in the film cooling. Numerical simulations based on the RANS method are conducted to evaluate the effects of film pre-cracking on its cooling and drag reduction performance, by changing the fuel conversion ratio from 0 to 40 %. Results show that the influence of film inlet cracking on its drag reduction performance is limited, and the relative change of the wall friction under different conversion ratios is less than 5 %. However, the film inlet cracking has a notable negative influence on its thermal protection performance. Specifically, for every 10 % increase in the film conversion ratio, the average adiabatic wall temperature will rise by about 20 K. Further analysis reveals that although the total amount of the fuel chemical heat sink is comparable to its physical heat sink, only around 25 % of the film chemical heat sink can be effectively used to enhance the fuel film cooling performance. The loss of the effective chemical heat sink during the pre-cracking process is the main reason for the decrease of film cooling performance as the film inlet conversion ratio increases.

EECH/CF: An Energy-efficient Cluster Head Election and Cluster Formation Algorithms for WSNs

Background and Objective: Wireless sensor networks (WSN) consist of sensor nodes with a limited battery life and limited communication distance. The minimal energy expended by the sensor nodes and network can be achieved either by reducing the number of communications or by controlling the topology. Thus, energy consumption can be optimized by employing several techniques, such as clustering. Clustering allows the network to be divided into a set of clusters, each of which is managed by a cluster head. In a hierarchical cluster-based WSN, the cluster head receives the data from its sensor members, aggregates it and sends the result to the base station, which leads to an extra overload. So, the selection of appropriate cluster head plays a very important role in conserving the energy of the sensor nodes and extend the lifetime of the network. This paper introduces an energyefficient cluster head election and cluster formation algorithm for WSNs, called EECH/CF. To select cluster heads, our proposal election algorithm uses the initial and residual energy level of the sensor nodes, and efficiently creates the different clusters using an appropriate mechanism. Performance evaluation has shown a significant improvement in energy conservation and the network lifetime for EECH/CF in comparison to some existing clustering algorithms. Methods: Our proposal election algorithm uses the initial and residual energy level of the sensor nodes, and efficiently creates the different clusters using an appropriate mechanism. Results and Discussion: Performance evaluation has shown a significant improvement in energy conservation and the network lifetime for EECH/CF in comparison to some existing clustering algorithms. Conclusion: Results show that our clustering algorithms improve the lifetime of the network as we expected. Indeed, the delay before the death of the first node can be up to seven times longer with EECH/CF.

New blow‐up criteria for a semilinear pseudo‐parabolic equation with general nonlinearity

This paper is concerned with the blow‐up phenomena for a semilinear pseudo‐parabolic equation with general nonlinearity under the null Dirichlet boundary condition. When the nonlinearity satisfies a new structural condition, we obtain some new blow‐up criteria with different initial energy levels and derive the growth estimations and life span of blow‐up solutions.