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This empirical study contributes to extend the literature on the nexus between energy consumption, financial development, economic growth, and urbanization in Pakistan. We use annual time series data covering the year from 1970 to 2018 and employ the Autoregressive Distributive lag (ARDL) and Granger causality test. The results of the ARDL-bound test confirm cointegration between the variables, as the null hypothesis of no cointegration is rejected. Further, the long-run results show that financial development and urbanization have positive correlation with energy demand. However, economic growth is negatively correlated with energy consumption. Similarly, in the short run, the financial market and urbanization stimulated energy demand. However, economic growth is insignificant with energy consumption. Besides that, a bidirectional relationship is noted between urbanization and energy consumption. Based on the finding, this empirical study suggests that policymakers and government should revisit their policies regarding economic growth, explore alternative sources of energy, and try to shift towards renewable energy, which is cheaper and eco-friendly.

In Wireless Sensor Network (WSN), node localization is a crucial need for precise data gathering and effective communication. However, high energy requirements, long inter-node distances and unpredictable limitations create problems for traditional localization techniques. This study proposes an innovative two-stage approach to improve localization accuracy and maximize route selection in WSNs. In the first stage, the Self-Adaptive Binary Waterwheel Plant Optimization (SA-BWP) algorithm is used to evaluate a node’s trustworthiness to achieve accurate localization. In the second stage, the Gazelle-Enhanced Binary Waterwheel Plant Optimization (G-BWP) method is employed to determine the most effective data transfer path between sensor nodes and the sink. To create effective routes, the G-BWP algorithm takes into account variables like energy consumption, shortest distance, delay and trust. The goal of the proposed approach is to optimize WSN performance through precise localization and effective routing. MATLAB is used for both implementation and evaluation of the model, which shows improved performance over current methods in terms of throughput, delivery ratio, network lifetime, energy efficiency, delay reduction and localization accuracy in terms of various number of nodes and rounds. The proposed model achieves highest delivery ratio of 0.97, less delay of 5.39, less energy of 23.3 across various nodes and rounds.

Nickel-Titanium (Ni-Ti) thin films have gained a lot of attention due to their unique features, such as the shape memory effect. Micro-actuators, micro-valve, micro-fluid pumps, bio-medical applications, and electronic applications have a lot of interest in these smart thin films. Sputter-deposited NiTi thin films have shown the potential to be very useful as a powerful actuator in micro-electro-mechanical systems (MEMS) because of their large recovery forces and high recoverable strains. Despite the advancement of improved deposition methods for the NiTi thin films, there are still certain unsolved challenges that impede accurate composition control throughout the deposition process. Many applications, spanning from the aerospace industries to a range of nanotechnologies, require knowledge of the sputtering characteristics of the materials that are subjected to bombardment, ejection, and deposition of ions. In recent decades, atomic scale modeling has been given a high emphasis in ion sputtering research, providing an adequate and precise description of collision cascades in solids using the Stopping and Range of Ions in Matter (SRIM) and Transport of Ions in Matter (TRIM). In this paper, SRIM is used to address how the heavy ions interact with the target materials. A variety of ion-solid interaction characteristics, including the sputter yield, have been determined by simulating collision cascades in the solids. On the other hand, TRIM was used to describe the range of ions that enter into the matter and cause damage to the target throughout the process. The simulation was carried out to compare the sputtering yield of Ni and Ti by varying the energy input (from 300V to 1300V). SRIM simulation was conducted by varying the thickness of the film, the angle of incidence of ions, and the energy involved in the sputtering process. The characterization of the films has been carried out using Field Emission Scanning Electron Microscopy (FESEM) to comprehend the surface and interface morphologies of the films and to validate the simulated results. With an increase in energy input (target voltage), the sputtering yield increased. The sputtering yield of the Ni target was higher than the Ti target indicating that Ni can be removed relatively easier than Ti.

The non-commuting graph of a non-abelian group $G$ with center $Z(G)$ is a simple undirected graph whose vertex set is $G\setminus Z(G)$ and two vertices $x,y$ are adjacent if $xy\ne yx$. In this paper, we compute Signless Laplacian spectrum and Signless Laplacian energy of non-commuting graphs of certain finite non-abelian groups. We obtain several conditions such that the non-commuting graph of $G$ is Q-integral and observe relations between energy, Signless Laplacian energy and Laplacian energy. In addition, we look into the hyperenergetic and hypoenergetic properties of non-commuting graphs of finite groups. We also assess whether the same graphs are Q-hyperenergetic and L-hyperenergetic.

In this study, we introduce a novel index called the modified inverse sum indeg (MISI) energy as an extension of the traditional inverse sum indeg (ISI) energy and neighbor degree sum energy. We devised an algorithm that employs the simplified molecular input line entry system (SMILES) formula of compounds to compute the MISI energy of polycyclic aromatic hydrocarbon (PAH). Additionally, we established the bounds of the MISI energy for certain classes of graphs with fixed number of vertices. A strong correlation between the MISI energy and the total $\pi$-electron energy of PAHs is observed through regression analysis. Remarkably, this correlation outperforms that achieved by the classical ISI energy. These findings highlight the enhanced effectiveness of the MISI energy as a descriptor for capturing significant molecular properties. Moreover, our study establishes a foundation for further theoretical extensions and practical applications in the field of chemical graph theory.

For a graph $G$ with $n$ vertices and $m$ edges, the energy (or the adjacency energy) is the sum of the absolute values of the eigenvalues (or adjacency eigenvalues) of $G$, that is, ${ℰ}(G)={\sum }_{i=1}^n|{\lambda }_i(G)|$, where ${\lambda }_i(G)$ is the $i\mathrm{\text{th}}$ adjacency eigenvalue of $G$. In this paper, we discuss the characteristic polynomial and the energy of dendrimers. We first show the formula obtained for the characteristic polynomial and the energy of tree dendrimers considered in Bokhary and Tabassum [The energy of some tree dendrimers, J. Appl. Math. Comput.68 (2022) 1033–1045] are incorrect. Using a different algorithmic procedure we will derive the correct formula for the characteristic polynomial and the energy of dendrimer $d(3,k)$. Further, we obtain the energy of $d(l,k)$ for $k=4$ and $k=5$, which partially answers a problem raised in Bokhary and Tabassum [The energy of some tree dendrimers, J. Appl. Math. Comput.68 (2022) 1033–1045].

Crude oil prices wield substantial influence over economic stability and sustainability, exerting a profound impact across various sectors and significantly moulding the economic well-being of nations. Thus, precision of predicting crude oil prices is of utmost importance for a wide array of stakeholders, including policymakers, investors, and participants in the energy market. This study offers an empirical exploration of the Seasonal Autoregressive Integrated Moving Average with Exogenous Variables (SARIMA-X) method, employing RMSE and MAPE values for forecasting crude oil prices during the most volatile periods from 2020 to 2023, including both COVID-19 pandemic and Russia Ukraine war period. The results indicate that the SARIMA-X method is effective for predicting crude oil prices during turbulent market conditions. This model can be a valuable tool for investors, traders, and other market participants, enabling them to make informed decisions when it comes to both intraday trading and long-term forecasting of crude oil prices.

The paper reviews some parts of classical potential theory with applications to two-dimensional fluid dynamics, in particular vortex motion. Energy and forces within a system of point vortices are similar to those for point charges when the vortices are kept fixed, but the dynamics is different in the case of free vortices. Starting from Euler’s and Bernoulli’s equations we derive these laws. Letting the number of vortices tend to infinity leads in the limit to considerations of equilibrium distributions, capacity, harmonic measure and many other notions in potential theory. In particular various kinds of Green functions have a central role in the paper, and we make a distinction between electrostatic and hydrodynamic Green functions. We also consider the corresponding concepts in the case of closed Riemann surfaces provided with a metric. From a canonically defined monopole Green function we rederive much of the classical theory of harmonic and analytic forms on Riemann surfaces. In the final section of the paper we return to the planar case, which then reappears in the form of a symmetric Riemann surface, the Schottky double. Bergman kernels, electrostatic and hydrodynamic, come up naturally as well as other kernels, and associated to the Green function there is a certain Robin function which is important for vortex motion, and which also relates to capacity functions in classical potential theory.

Intrinsic time-scale decomposition (ITD) is a new nonlinear method of time-frequency representation which can decipher the minute changes in the nonlinear EEG signals. In this work, we have automatically classified normal, interictal and ictal EEG signals using the features derived from the ITD representation. The energy, fractal dimension and sample entropy features computed on ITD representation coupled with decision tree classifier has yielded an average classification accuracy of 95.67%, sensitivity and specificity of 99% and 99.5%, respectively using 10-fold cross validation scheme. With application of the nonlinear ITD representation, along with conceptual advancement and improvement of the accuracy, the developed system is clinically ready for mass screening in resource constrained and emerging economy scenarios.

The source-network, the dynamic trophic level and the energy are incorporated into a "unified" model that describes both micro- and macroevolutions within a single theoretical framework. This model describes the microevolution in details by accounting for the birth, ageing, and natural death of individual organisms as prey-predator interactions on a hierarchical dynamic food web. It also provides a natural description of random mutations and speciation of species as well as their extinctions. The distribution of lifetimes of species follows an approximate power law only over a limited regime, and the distribution of trophic level follows an exponential attenuation.

The rise of empires can be elucidated by treating them as living organisms, and the celebrated Verhulst or Lotka–Volterra dynamics can be used to understand the growth mechanisms of empires. The fast growth can be expressed by an exponential function as in the case of Macedonian empire of the Alexander the Great whereas a sigmoidal growth can be expressed by power-law equation as in the case of Roman and Ottoman empires. The superpowers Russia and the USA follow somehow different mechanisms, Russia displays two different exponential growth behaviors whereas the USA follows two different power-law behaviors. They did not disturb and mobilize their social capacity much during the course of their rise. The decline and the collapse of an empire occur through a kind of fragmentation process, and the consequently formed small states become rather free in their behavior. The lands of the new states formed exhibit a hierarchical pattern, and the number of the states having an area smaller than the largest one can be given either by an exponential or power-law function. The exponential distribution pattern occurs when the states are quite free in their pursuits, but the power-law behavior occurs when they are under the pressure of an empire or a strong state in the region. The geological and geographical conditions also affect whether there occurs exponential or power-law behavior. The new unions formed such as the European Union and the Shanghai Cooperation increase the power-law exponent implying that they increase the stress in the international affairs. The viscoelastic behavior of the empires can be found from the scattering diagrams, and the storage $(G^{\prime })$and loss modulus $(G^{\prime \prime })$, and the associated work-like and heat-like terms can be determined in the sense of thermodynamics. The $G^{\prime }$ of Ottomans was larger than that of Romans implying that they confronted severe resistance during their expansion. The $G^{\prime }$ of Russia is also larger than that of the USA; in fact the USA did not face severe resistance as they had an overwhelming superiority over native Americans. The $G^{\prime }>G^{\prime \prime }$ indicates solidity in the social structure and Romans, Ottomans, and Russians all have $G^{\prime }$ larger than $G^{\prime \prime }$. The $G^{\prime }$ is slightly larger than $G^{\prime \prime }$ for the USA indicating that they have had a very flexible social structure. By the same token the ratio of the work-like term to the internal energy is larger for Ottomans than that of Romans, and larger for the USA than that of Russia. That means the fraction of the total energy allocated to improve the social capacity is larger for Romans than that of Ottomans, and is larger for Russians than that of the USA.

A solid–solid contact model of a rough surface with a single peak was established to explore the thermal effect of interfacial friction. From the perspective of friction force, temperature and energy, the law of the thermal effect was revealed. The results showed that the temperature of the asperities gradually increased during the shearing process, and a stress concentration formed in the shearing zone. After contact, the asperities had undergone unrecoverable plastic deformation. At each indentation depth, as the rotation angle of the crystal increased, the friction force, average temperature, and the sum of the changes in thermal kinetic and thermal potential energy first increased and then decreased; the trends of the three parameters changing with the rotation angle of the crystal were consistent. The average decreases in the friction force, average temperature, and the sum of the changes in thermal kinetic and thermal potential energy were 52.47%, 30.91% and 56.75%, respectively, for a crystal structure with a rotation angle of 45^∘ compared to a crystal structure with a rotation angle of 0^∘. The methods used in this study provide a reference for the design of frictional pairs and the reduction of the thermal effect of interfacial friction.

We aim at mapping streaming applications that can be modeled by a series-parallel graph onto a 2-dimensional tiled chip multiprocessor (CMP) architecture. The objective of the mapping is to minimize the energy consumption, using dynamic voltage and frequency scaling (DVFS) techniques, while maintaining a given level of performance, reflected by the rate of processing the data streams. This mapping problem turns out to be NP-hard, and several heuristics are proposed. We assess their performance through comprehensive simulations using the StreamIt workflow suite and randomly generated series-parallel graphs, and various CMP grid sizes.

We consider the problem of scheduling an application on a parallel computational platform. The application is a particular task graph, either a linear chain of tasks, or a set of independent tasks. The platform is made of identical processors, whose speed can be dynamically modified. It is also subject to failures: if a processor is slowed down to decrease the energy consumption, it has a higher chance to fail. Therefore, the scheduling problem requires us to re-execute or replicate tasks (i.e., execute twice the same task, either on the same processor, or on two distinct processors), in order to increase the reliability. It is a tri-criteria problem: the goal is to minimize the energy consumption, while enforcing a bound on the total execution time (the makespan), and a constraint on the reliability of each task. Our main contribution is to propose approximation algorithms for linear chains of tasks and independent tasks. For linear chains, we design a fully polynomial-time approximation scheme. However, we show that there exists no constant factor approximation algorithm for independent tasks, unless P=NP, and we propose in this case an approximation algorithm with a relaxation on the makespan constraint.

The aim of this study was to examine the effects of Qi therapy (QT) on the symptoms of chronic fatigue syndrome (CFS), including fatigue and complications. QT affected the experience of mental and emotional relaxation in the subjects of these case studies, who also gained strength to overcome their pain and fatigue. Although the results of these two case studies may not constitute conclusive evidence, they provide a foundation for the exploration of QT as a complementary therapy in the reduction of negative symptoms of chronic fatigue syndrome.

Low-intensity qigong exercise has been suggested as an alternative to more vigorous exercise when striving for health benefits. The purpose of this study was to investigate whether self-determined motivation and perceived stress are related to concentration during exercise, and to the amount of exercise carried out. Leisure-time qigong exercisers (n = 279) were assessed by using the Sport Motivation Scale, Stress and Energy Scale, and by self-rated Concentration. Exercise sessions per week, Session time, and ability to Set a time for exercise, and perceived Disturbance during exercise were also recorded. Participants who were in a Calm energy mood (low-stress, high-energy, able to set a time for exercise), displayed an increased Concentration on qi-flow (R² = 0.13) during exercise. An elevated stress-level correlated negatively with Health, Energy, Concentration, Sessions per week, Session time, Sessions performed during the previous week, ability to Set a time for exercise, and feeling Undisturbed during exercise (all p < 0.01). Intrinsic motivation was positively correlated with Concentration (0.24, p < 0.01) and negatively correlated with Stress (-0.19, p < 0.05). Individuals who adhere to a regular qigong exercise regimen are more intrinsically motivated, less stressed, and more concentrated while exercising than those who do not adhere to a regular regime. This suggests that health-professionals need to be aware of these factors when prescribing qigong exercise for health benefits.

Assessment of energy and environmental issues has received a special focus due to global warming and climate vulnerabilities. Energy, environment and economic development simultaneously yielded a combined effect, which is favorable from the economic point of view while unfavorable for environmental aspects. It is necessary to measure the energy, economic and environmental performance with appropriate methods. Therefore, this study measures the energy security and environmental efficiency. Data used in this study were collected from the official website of International Energy Agency (IEA), British Petroleum (BP) and World Bank. We employ a non-radial DEA technology for assessing energy and environmental efficiency for OECD countries. Results reveal that the values of energy intensity range from 0.93 to 0.30, while GHG emission per capita values range from 24.61 to 5.28. As far as energy efficiency is concerned, Iceland and Greece have the highest value (0.99) of energy efficiency, whereas Ireland has the lowest value (0.34) of energy efficiency. Further analysis shows that Austria, Australia, Portugal and Spain have values between 0.70 and 0.80 for energy intensity, whereas UK, Sweden, Germany and the USA have values of energy intensity, between 0.40 and 0.50. The study proposes some valuable policy implications for policy and decision-makers to make the environment more sustainable.

We obtain the energy of a conformal scalar dyon black hole (CSD) by using the energy–momentum complexes of Tolman and Möller. The total gravitational energy is given by the CSD charge in both prescriptions.

We consider an anti de Sitter universe filled by quantum CFT with classical phantom matter and perfect fluid. The model represents the combination of a trace-anomaly annihilated and a phantom driven anti de Sitter universes. The influence exerted by the quantum effects and phantom matter on the AdS space is discussed. Different energy conditions in this type of universe are investigated and compared with those for the corresponding model in a de Sitter universe.

We give three different spherically symmetric spacetimes for the coupled gravitational and electromagnetic fields with charged source in the tetrad theory of gravitation. One of these contains an arbitrary function and generates the others. These spacetimes give the Reissner–Nordström metric black hole. We then calculated the energy associated with these spacetimes using the superpotential method. We find that unless the time-space components of the tetrad field go to zero faster than at infinity, one gets different results for the energy.