International Journal Of Nonlinear Analysis And Applications
Volume:16 Issue: 8, Aug 2025

In this paper, we introduce several regularity properties for the non-differentiable convex-like $C(T)$-valued functions which are defined on a Hilbert space.  The relationships with various regularity properties are investigated. All results are given in terms of the convex subdifferential. Non-trivial numerical examples are incorporated to demonstrate the validity of the results established in this paper. To the best of our knowledge, this paper is the first to investigate the regularity properties for the $C(T)$-valued functions, even in the differentiable case of finite-dimensional spaces.

The temperature of the exhaust gases from simple gas turbines is high, and therefore, gas turbines have low thermal efficiency. Also, high ambient air temperature reduces the output power and thermal efficiency of the cycle. This paper examines a system that uses a heat recovery boiler to recycle exhaust gases and produce steam. Steam is produced in a double-pressure boiler. Low-pressure steam is introduced into the lithium bromide single-acting absorption chiller to cool the air entering the compressor, and high-pressure steam is injected into the combustion chamber of the gas turbine. The main purpose of this paper is to study and analyse (energy, exergy and environmental) gas turbine system with steam injection with cooling of the inlet air. The gas turbine cycle of the Zahedan gas power plant was modelled based on Heat Recovery Steam Injection (HRSG). Then energy and exergy are carried out. Also, the effect of steam injection and inlet air cooling on heat efficiency, output power, fuel consumption, exergy efficiency and total system price was studied and presented. The results showed that with a 10% spray of steam inside the combustion chamber, the output power increased by 11.03% and the thermal efficiency of the cycle increased from 24.4% to 26%.

This research was conducted to present a model of information technology acceptance in internal auditing using the fuzzy Delphi approach. In this study, a sample of 15 financial managers, internal auditors from companies, and audit experts was utilized, employing a non-random and judgmental sampling method. The fuzzy Delphi method was employed for screening the factors. Accordingly, the factors were initially identified as 38 factors for the experts, and through the fuzzy Delphi approach, they were reduced to 12 factors in three stages. Subsequently, a structural interpretive model was used to determine the significance and prerequisites of the validated factors. Ultimately, a four-level model of factors influencing the acceptance of information technology in internal auditing was identified. Considering that each category of factors consisted of a set of variables that were examined, the analysis of the data determined their order. The variables for the first to fourth levels are as follows: Level 1: Specialized training, management awareness, management support and encouragement, auditor's trust in technology adoption, and audit report quality. Level 2: Specialized training, management awareness, management support and encouragement, and audit report quality. Level 3: Specialized training for auditors, management support and encouragement. Level 4: Specialized training for auditors. Finally, based on the findings of the research, recommendations were provided for management and employees, as well as suggestions for other researchers.

By anticipating financial turmoil, it is possible to take the necessary precautions before financial distress occurs by managers and investors. This study compares two algorithms for predicting bankruptcy using an Artificial Neural Network (ANN) and Neural network optimized metaheuristic Firefly Algorithm (FA). To run the test, initial values are first set for the network weights and biases. Then, during optimization, the FA algorithm generates a population of different weights and biases. The conversion function used in the output layer is linear, and a non-linear sigmoid function is selected for the middle layer. To conduct this research, the data of 79 companies listed on TSE from 2012 to 2015 were collected and analyzed statistically by backpropagation neural network and FA algorithms. The results show that FA, compared to ANN predicted the companies’ bankruptcy much better. Also, the FA Algorithm maintains a good correlation between bankrupt and non-bankrupt companies, just like real data.

This research was carried out to present the internal auditors' coping strategy model with an interpretative structural approach. From the point of view of the result of its implementation, the upcoming research is applied research, to implement exploratory research and descriptive research using a survey method. The information required for the research to provide the model was collected using semi-structured interviews from 11 experts in the subject field of the research, i.e. people in the accounting and auditing profession who had more than 15 years of work experience in the field of internal audit. In this research, a coping strategy model for internal auditors was designed using Interpretive Structural Modeling (ISM). The results of the interpretive structural analysis (ISM) by the exploratory model showed that brain software coping strategies include financial intelligence, accounting and auditing, clear recognition of roles and responsibilities and the development of internal auditors' skills with training, hardware coping strategies including continuous communication between managers and employees, reporting Physical errors and defects and continuous inspections, software coping strategies including systematic review and analysis of reports, performance evaluation processes and upgrading internal audit technologies lead to the reduction of conflicts of internal auditors including personal conflict, conflict of duties, conflict of job position and conflict of interests.

In this article‎, ‎we introduce refinements of Young-type inequalities for scalars‎. ‎We then extend these inequalities to encompass versions based on Hilbert-Schmidt and trace norms‎. ‎The results presented in this paper represent refinements of the findings originally established by Nasiri and Shakoori [6].

Uncertainty in the capital market means the difference between the expected values and the values that occur in reality. The design of different analysis and forecasting methods in the capital market is also due to the high value and the need to know prices in the future with more certainty or less uncertainty. To earn profit in the capital market, investors have always sought to find the right share for investment and the right price for buying and selling, and therefore all the forecasting models proposed have always sought to answer three basic questions; What share, in what time frame and at what price should be bought or sold. In this article, we will use the combined method based on LSTM and a neural fuzzy system to predict stock prices in the Iranian market. The results show that the proposed method has an accuracy of over 90% in stock price prediction.

The purpose of this study is to investigate the impact of oil price shocks on the exchange rate fluctuations of selected Persian Gulf countries, including Saudi Arabia, Kuwait, Iraq, and Iran, from 2000 to 2023 using the structural autoregression (SVAR) model. The findings of this research showed that the coefficients of oil supply shocks are significant only in Saudi Arabia and are no longer statistically significant in the other three countries. Coefficients of delays are statistically significant only for the country of Saudi Arabia in the first Intermission. Furthermore, regarding the coefficients of total demand shocks on exchange rate fluctuations of these countries, it does not have a significant impact on any of the countries. The results regarding the interruptions of the demand shock also indicate that statistically only the first interruption is significant for Kuwait. In addition, the impact of specific oil demand shocks on exchange rate fluctuations is significant for Kuwait. Therefore, it can be said that no strong, stable, or long-term effects of the structural shocks of oil supply and demand were found in the currencies of these countries.

The Sharpe ratio is one of the performance evaluation criteria of the stock portfolio, which shows the return per unit of risk. This ratio is particularly important for risk-averse investors. In the current research, the hidden Markov model approach introduces a new stock portfolio model called the maximum predictability portfolio of the Sharpe ratio. The hidden Markov model used for each hidden state has a mixture of normals distribution output, which is used to calculate the return and standard deviation to calculate the Sharpe ratio in the investment horizon. The research portfolio calculates the weights of the portfolio in such a way that the Sharpe ratio is maximized in the horizon of the portfolio. The optimal research portfolio was optimized using the historical data of 10 indices from the Tehran Stock Exchange between 2018 and 2018 in a four-member mode space. The evaluation of the performance of the optimal portfolio in the Sharpe ratio criterion shows that the research model has a better performance than the mean-variance model and the equal-weight model.

One of the basic problems in the “Calculus of Variations” is the minimization of the following functional:$$F(x)=\int_a^b f(t,x(t),x'(t)) dt,$$over a class of functions $x$ defined on the interval $[a,b]$. According to a regularity theorem, solutions to this fundamental problem are found in a smaller class of more regular functions. However, they were originally considered to belong to a larger class. In this context, two theorems attributed to “Hilbert-Weierstrass” and “Tonelli-Morrey” are two classical studies of the regularity of discussion for the solutions to this problem. As higher-order differential equations and higher-order optimal control problems become more prevalent in the literature, regularity issues for these problems should receive more attention. Therefore, a generalization of the above regularity theorems is presented here, namely the regularity of solutions to the following functional$$F(x)=\int_a^b f(t,x(t),x'(t),\dots,x^{(n-1)}(t)) dt$$where $n \geq 2$. It is expected that this extension will be helpful in discussing the regularity of higher-order differential equations and optimal control problems.

In this paper, we study weighted composition operators on extended analytic Lipschitz algebras ${\rm Lip}_{A}(X,K,\alpha)$ where $X$ is a compact plane set, $K$ is a closed subset of $X$ with nonempty interior and $0 < \alpha \leq 1$. We first give necessary conditions and sufficient conditions on a function $u \in \mathbb{C} ^{X}$ and self-map $\varphi$ of $X$ for which $T=uc_{\varphi}$ to be a weighted composition operator on ${\rm Lip}_{A}(X,K,\alpha)$. We next give the necessary conditions for these operators to be compact and provide some sufficient conditions for the compactness of such operators.

Improving income distribution is considered as one of the components of economic development in the Iranian economy, especially in the years after the Islamic Revolution. Due to the dependence of the government budget on oil revenues (40%) and the high share of subsidies in the annual budget (10%) of the Iranian economy, fluctuations in the global oil market, sanctions imposed in this area and the subsequent uncertainty in the realization of Oil revenues can affect government budgets and revenue distribution. In this study, to study the effect of drug price liberalization on inequality and income distribution using the Gini coefficient index, the integrated data model in the period 2010: 1 to 2019: 4 has been used. The results show that drug price liberalization has a negative and significant effect on the level of income distribution in the short run.

This study aimed to design a human resource agility model in the Tax Affairs Organization based on the government's agility policies on 376 senior and middle managers of the country's tax affairs organization. The current applied research is quantitative in terms of data collection method. The primary data collection tool is the questionnaire made by the researcher in the department. The validity of the questionnaire was confirmed using the content validity method. Cronbach's alpha coefficient was calculated to evaluate the reliability of the questionnaire. Cronbach's alpha coefficient was more than 0.7, indicating good reliability. The partial least squares technique and SmartPLS software were used to test the hypotheses. The government's agility policies positively and significantly impacted human resource management, organizational values, and job design. Organizational improvement strategy positively and significantly affected human resources management, organizational values, and job design. Human resource management had a positive and significant impact on the development of human resources. Organizational values positively and significantly affected human resources development and resilience capabilities.

The main purpose of this work is to introduce and investigate fuzzy quantum calculus. Our idea begins with a general definition of fuzzy $q$-derivative on arbitrary time scales using the generalized Hukuhara difference. It compiled some basic facts in the fields of the fuzzy $q$-derivative and the fuzzy $q$-integral and proved them in detail. Proceed with this work, specifying the particular concept of fuzzy $q$-Taylor's expansion, especially for continuous and fuzzy valued functions which are non-differentiable in the classical (usual) concept, as the best tool for approximating functions and solving the fuzzy initial value $q$-problems. Eventually, some numerical examples of fuzzy $q$-Taylor's expansion of special functions and functions with switching points, are solved for illustration.

In this paper, we introduce and investigate a subclass  $\mathcal{G}_{\Sigma}^{h,p}(\lambda,m,n, \alpha,\gamma)$ of bi-univalent functions in the open unit disk $\mathbb{U}$. Upper bounds for this class's second and third coefficients of functions are found. The results, which we have presented in this paper, would generalize and improve some recent works of several earlier authors.