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Non-cooperative intelligent control agents (ICAs) with dedicated cost functions, can lead the system to poor performance and in some cases, closed-loop instability. A robust solution to this challenge is to place the ICAs at the feedback Nash equilibrium point (FNEP) of the differential game between them. This paper introduces the designation of a robust decentralized infinite horizon LQR control system based on the FNEP for a linear time-invariant system. For this purpose, two control strategies are defined. The first one is a centralized infinite horizon LQR (CIHLQR) problem (i.e. a supervisory problem), and the second one is a decentralized control problem (i.e. an infinite horizon linear-quadratic differential game). Then, while examining the optimal solution of each of the above strategies on the performance of the other, the necessary and sufficient conditions for the equivalence of the two problems are presented. In the absence of the conditions, by using the least-squares error criterion, an approximated CIHLQR controller is presented. It is shown that the theorems could be extended from a two-agent control system to a multi-agent system. Finally, the results are evaluated using the simulation results of a Two-Area non-reheat power system.

The Artificial Bee Colony (ABC) Algorithm is a sophisticated optimization technique that is inspired by the intelligent behaviors of honey bee swarms. These behaviors, such as foraging and communication within complex social structures, serve as the foundation for the algorithm's effectiveness. In this paper, the ABC algorithm is utilized to optimize the design of reinforced cantilever concrete retaining walls, with the goal of minimizing both cost and weight. The results are compared to existing literature, demonstrating the success of the ABC algorithm in achieving the objectives. Furthermore, a comparison is conducted between the optimized design and a conventional manual design, revealing a significant reduction in cost and weight through optimization. Additionally, two types of reinforced concrete cantilever retaining walls-a T-shape wall with variable stem thickness and a standard T-shape wall-are presented and compared, considering their differing variables and constraints. These comparisons are made for two objective functions: the cost and weight of the wall. To further investigate the impact of initial parameters, such as the unit weight of soil and stem height, a sensitivity analysis is conducted. The robustness of the ABC algorithm in optimizing the cost and weight of reinforced concrete cantilever retaining walls is demonstrated by the results.

One of the obvious reasons for most disorders in network service provisioning is network path congestion. Congestion avoidance in today's networks is too costly and sometimes impossible. With the introduction of SDN, centralizing the equipment's control plane has become possible. This paper presents an enhanced method named ESV-DBRA to avoid congestion in multi-tenant SDN networks. At first, ESV-DBRA monitors the traffic load and delay of all network paths for each tenant individually. Then, by merging the parameters obtained from the monitoring, the Service Level Agreements (SLA), and a novel proposed cost function, it calculates the cost of the network paths per tenant. As a result, traffic for each tenant is routed through the path/paths at the lowest possible cost from the tenant's perspective. Next, the bandwidth quotas will be calculated and assigned to the tenants over their optimal routes. Afterward, whenever congestion is likely to occur in a path, ESV-DBRA automatically changes the route or bandwidth of the tenants' traffic related to this path to avoid congestion. Related algorithms are also proposed.Eventually, simulations show that the proposed method effectively increases bandwidth utilization by 10.76%.

Evaluating the cutting rate (CR) of stones is important in the cost estimation and the planning of the stone processing plants. This research used regression models to estimate the stones’ CR based on their physico-mechanical characteristics. Stone processing factories in Mahallat City (Markazi province, Iran) were visited, and the CR of diamond circular saws was recorded on six different travertine stones. Next, the stone block samples were collected from the quarries for laboratory tests. Stones’ porosity (n), uniaxial compressive strength (UCS), and Schmidt hammer hardness (SH) were determined in the laboratory as their physico-mechanical characteristics. Correlation relationships of CR with physico-mechanical characteristics were evaluated using simple and multiple regression analyses, and estimator models were developed. Results showed that multiple regression models are more reliable than simple regression for estimating the stones’ CR. The validity of the developed multiple regression models was verified with the published data of one researcher. The findings indicated that these models are accurate enough for estimating the CR of stones. Consequently, the multiple regression models provide practical advantages for estimating the CR and save time and cost during the planning and design of the stone processing factories.

مسائل حمل و نقلی به سه سطح استراتژیک، تاکتیکی و کارکردی دسته بندی می شود که هریک سطح نفوذ، میزان بودجه مورد نیاز، تصمیم گیران و دوره زمانی متفاوتی دارند. مسئله طراحی و توسعه شبکه حمل و نقل ریلی یکی از مسائل مهم و کلیدی از سطح استراتژیک است. به طور خلاصه، طراحی شبکه به نحوه اختصاص دادن بودجه محدود به توسعه زیرساخت شبکه ریلی می پردازد، به گونه ای که هدفهای خاصی همچون کمینه سازی کل زمان سفر در شبکه، کمینه-سازی هزینه های توسعه یا نگهداری شبکه، بیشینه سازی درآمد حاصله از انتقال بار، یا بیشینه سازی جذب تقاضای سفر به سوی شیوه ریلی لحاظ شود. شکل عمومی مساله طراحی شبکه یک مسئله دوسطحی در رده مسائل NP-Hard به شمار می رود که حل آن در مقیاس های کوچک با دشواری روبروست. در این مقاله برای حل مسئله طراحی شبکه یک الگوریتم حریصانه ارایه می شود که سعی در کاهش هرچه بیشتر هزینه های توسعه شبکه دارد. الگوریتم با این هدف طراحی شده است که اولویت توسعه شبکه را به بلاک های با کمترین هزینه توسعه می دهد و این روند تا جایی پیش می رود که کل سطح تقاضای ورودی بتواند از شبکه انتقال پیداکند. این الگوریتم با زبان جاوا پیاده سازی شد و شبکه راه آهن ایران به عنوان مطالعه موردی استفاده شد. با توجه به ماهیت دو هدفی در مسئله، تقاضای عبوری و توسعه در شبکه، جواب های "شبه پاریتو" با درصد های متفاوت از اهمیت این دو هدف مورد بحث و بررسی قرار گرفت و نتایج الگوریتم پیشنهادی تحلیل گردید.