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In this article, we study the asymptotic behavior of even-order neutral delay differential equation (a⋅(u+ρ⋅u∘τ)(n−1))′(ℓ)+h(ℓ)u(g(ℓ))=0,ℓ≥ℓ0,{(a\cdot {(u+\rho \cdot u\circ \tau )}^{(n-1)})}^{^{\prime} }(\ell )+h(\ell )u(g(\ell ))=0,\hspace{1.0em}\ell \ge {\ell }_{0}, where n≥4n\ge 4, and in noncanonical case, that is, ∫∞a−1(s)ds

This study is concerned with investigating the oscillatory properties of a general class of neutral differential equations. Neutral equations are characterized by being rich in both practical and theoretical aspects. We obtain criteria that guarantee the oscillation of solutions to a fourth-order neutral differential equation with multiple delays. Considering the canonical case, we obtain some new relations and inequalities that help in obtaining improved criteria. We use the reduction method to relate the oscillation of the studied equation to a first-order equation. We apply the results to a special case. Through this application, we evaluated the efficiency of the new results in the oscillation test compared to previous results in the literature. [ABSTRACT FROM AUTHOR]

In this study, we aim to contribute to the increasing interest in functional differential equations by obtaining new theorems for the oscillation of second-order neutral differential equations of mixed type in a non-canonical form. The results obtained here improve and extend those reported in the literature. The applicability of the results is illustrated by several examples. [ABSTRACT FROM AUTHOR]

This paper aims to study the asymptotic properties of nonoscillatory solutions (eventually positive or negative) of a class of third-order canonical neutral differential equations. We use Riccati substitution to reduce the order of the considered equation, and then we use the Philos function class to obtain new criteria of the Kamenev type, which guarantees that all nonoscillatory solutions converge to zero. This approach is characterized by the possibility of applying its conditions to a wider area of equations. This is not the only aspect that distinguishes our results; we also use improved relationships between the solution and the corresponding function, which in turn is reflected in a direct improvement of the criteria. The findings in this article extend and generalize previous findings in the literature and also improve some of these findings. [ABSTRACT FROM AUTHOR]

This paper aims to study a class of neutral differential equations of higher-order in canonical form. By using the comparison technique, we obtain sufficient conditions to ensure that the studied differential equations are oscillatory. The criteria that we obtained are to improve and extend some of the results in previous literature. In addition, an example is given that shows the applicability of the results we obtained. [ABSTRACT FROM AUTHOR]

The aim of the paper is to study the oscillation behavior for third-order differential equations with several delays and with p-Laplacian operator. Our technique bases essentially on the presentation of sharper estimates of positive solutions of the equation studied using an iterative method. What is more, the iterative nature of the new criteria allows us to check for oscillation of all solutions, even if the known findings relevant to this fail to apply. [ABSTRACT FROM AUTHOR]

In this paper, exergy analysis of a 210 MW SPP (Steam Power Plant) is performed. Firstly, the plant is modeled and validated, followed by a parametric study to show the effects of various operating parameters on the performance parameters. The net power output, energy efficiency, and exergy efficiency are taken as the performance parameters, while the condenser pressure, main steam pressure, bled steam pressures, main steam temperature, and reheat steam temperature isnominated as the operating parameters. Moreover, multiple polynomial regression models are developed to correlate each performance parameter with the operating parameters. The performance is then optimizedby using Direct-searchmethod. According to the results, the net power output, energy efficiency, and exergy efficiency are calculated as 186.5 MW, 31.37 and 30.41%, respectively under normal operating conditions as a base case. The condenser is a major contributor towards the energy loss, followed by the boiler, whereas the highest irreversibilities occur in the boiler and turbine. According to the parametric study, variation in the operating parameters greatly influences the performance parameters. The regression models have appeared to be a good estimator of the performance parameters. The optimum net power output, energy efficiency and exergy efficiency are obtained as 227.6 MW, 37.4 and 36.4, respectively, which have been calculated along with optimal values of selected operating parameters.

In this paper, thermodynamic analysis of 210 MW dual-fire, subcritical, reheat steam power plant, situated near Jamshoro, Pakistan has been performed. Firstly, the plant is modeled by EES (Engineering Equation Solver) software. Moreover; a parametric study is performed to assess the impacts of various operating parameters on the performance. The net power output, energy efficiency and exergy efficiency are considered as performance parameters of the plant whereas, condenser pressure, main steam pressure and main steam temperature are nominated as operating parameters. According to the results, the net power output, energy efficiency and exergy efficiency are determined as 186.5 MW, 31.37% and 30.41% respectively, under design operating conditions. The condenser contributed a major share in the total energy loss i.e. 280 MW (68.7%) followed by boiler with 89 MW (21.8%). The major exergy destructing area is found in the boiler with 350 MW (82.11%) of the total exergy destruction followed by turbine with 43.1 MW (10.12%) and condenser 12 MW (5.74 %). According to the parametric study, variation in operating parameters had great influence on the plant performance

In this work, we present a new technique for the oscillatory properties of solutions of higher-order differential equations. We set new sufficient criteria for oscillation via comparison with higher-order differential inequalities. Moreover, we use the comparison with first-order differential equations. Finally, we provide an example to illustrate the importance of the results. [ABSTRACT FROM AUTHOR]