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The most general purpose of the current paper is to trace and discuss the history and state of the art of studies on vehicle motion (dynamics) in a transition curve above the critical velocity, with the aim of potentially increasing the circle of researchers involved in studying this issue and strengthening the will of the authors to continue their studies. This general goal is achieved in two ways: first, through a profiled literature analysis, showing the historical progress and current state of the research; and second, through reference to the history of stability studies as an example of selected studies' development. In addition, this work has two more specific goals. Together, they consist of collecting the literature in a related field in one place and analyzing it on site to accomplish the review. Both specific goals are attained by dividing the literature into two corresponding parts. In the first part, the current issues of rail vehicle stability are analyzed and divided into four problems. The second part includes works that deal with the subject of the motion and dynamics of a rail vehicle on a transition curve section. Here, the works are divided into five groups and discussed. They are put in order from the closest to the furthest from this paper's main subject; however, the last group includes the most recent references. In addition, information on the authors' approach to the problem is provided, including the methods and models used, as well as example results. Based on the analysis of the literature and the state of the art, a summary of the analysis is presented at this paper's end. It highlights the small number of works on the subject of interest, and based on the review of stability studies, it seeks to encourage present and potential authors to study this field and share their results with society. [ABSTRACT FROM AUTHOR]

The shielding calculation of neutron streaming problems with ducts is characterized by the strong anisotropy of angular flux, which poses a challenge for the analysis of nuclear installations. The discrete ordinate method is one of the most commonly deterministic techniques to solve the neutron transport equation, in which the accuracy and efficiency neutron are crucial to ensure the reliability of the streaming shielding simulation. We implemented the goal-oriented multi-collision source algorithm in the 3D transport code ARES. This algorithm can determine the importance factor based on the adjoint transport calculation, obtain the response function to enable problem-dependent, goal-oriented spatial decomposition, and provide the error estimation as a driving force behind the dynamic quadrature to optimize the source iteration. This study focuses on verifying the goal-oriented multi-collision source algorithm under the neutron streaming problems, and the capabilities of the algorithm have been tested on IRI-TUB benchmark of SINBAD database. The numerical results show that the algorithm can effectively control the angular discretization error for the neutron streaming problems, which is more economical than the traditional discrete ordinate calculation. [ABSTRACT FROM AUTHOR]

With stricter IMO regulations on CO2 taking effect in 2023 and ambitious goals to reduce carbon intensity by 2030, the maritime industry is scrambling to clean up its act. Conventional methods and equipment are now being reevaluated, upgraded or completely replaced. The difference between a short-term fix and a long-term sustainable option is how flexible vessels will be to use new energy sources or technology as they become viable. The review discusses the recent literature on renewable energy sources, technical and operational strategies for new and existing ships, technology maturity, and alternative fuels. It is found that the IMO's targets can be met by combining two or three technologies, or via a radical technology shift which can provide innovative, high-efficiency solutions from an environmental and economic standpoint. It has also been noted that policies and enforcement are essential management instruments for mitigating the unfavourable environmental effects of marine transportation and directing the maritime industry toward sustainability on a regional, national, and international scale. [ABSTRACT FROM AUTHOR]

Many industries apply traditional controllers to automate manual control. In recent years, artificial intelligence controllers applied with deep-learning techniques have been suggested as advanced controllers that can achieve goals from many industrial domains, such as humans. Deep reinforcement learning (DRL) is a powerful method for these controllers to learn how to achieve their specific operational goals. As DRL controllers learn through sampling from a target system, they can overcome the limitations of traditional controllers, such as proportional-integral-derivative (PID) controllers. In nuclear power plants (NPPs), automatic systems can manage components during full-power operation. In contrast, startup and shutdown operations are less automated and are typically performed by operators. This study suggests DRL-based and PID-based controllers for cold shutdown operations, which are a part of startup operations. By comparing the suggested controllers, this study aims to verify that learning-based controllers can overcome the limitations of traditional controllers and achieve operational goals with minimal manipulation. First, to identify the required components, operational goals, and inputs/outputs of operations, this study analyzed the general operating procedures for cold shutdown operations. Then, PID- and DRL-based controllers are designed. The PID-based controller consists of PID controllers that are well-tuned using the Ziegler–Nichols rule. The DRL-based controller with long short-term memory (LSTM) is trained with a soft actor-critic algorithm that can reduce the training time by using distributed prioritized experience replay and distributed learning. The LSTM can process a plant time-series data to generate control signals. Subsequently, the suggested controllers were validated using an NPP simulator during the cold shutdown operation. Finally, this study discusses the operational performance by comparing PID- and DRL-based controllers. [ABSTRACT FROM AUTHOR]

With every passing second, we witness the effect of the global environmental impact of fossil fuels and carbon emissions, to which nations across the globe respond by coming up with ambitious goals to become carbon-free and energy-efficient. At the same time, electric vehicles (EVs) are developed as a possible solution to reach this ambitious goal of making a cleaner environment and facilitating smarter transportation modes. This excellent idea of shifting towards an entirely EV-based mobility industry and economy results in a range of issues that need to be addressed. The issues range from ramping up the electricity generation for the projected increase in consumption to developing an infrastructure that is large enough to support the higher demand for electricity that arises due to the market penetration of EVs. Vehicle to grid (V2G) is a concept that is largely in a testing phase in the current scenario. However, it appears to offer a solution to the issues created by a mobility sector that the constantly growing EV fleet will dominate. Furthermore, the integration of EVs with the grid seems to offer various cost-wise and environment-wise benefits while assisting the grid by tapping into the idle energy of parked EVs during peak hours. This review aims to present some of the possible ancillary service potentials of such a system while also discussing the potential challenges, impacts, and future market penetration capabilities of V2G technology. [ABSTRACT FROM AUTHOR]

The EU's energy policy is geared towards introducing changes in order to stop or avoid negative climate change. The determinants of the energy policies of Poland and Germany are presented along with the priorities until 2050. The possibilities of reducing the impact of energy on the environment were interpreted, emphasizing its common goal. Activities supporting the EU and maintaining the level of energy security are indicated. Possible negative effects in the social and health sphere are presented as a response to the failure to implement these demands. The literature was analyzed and proprietary questionnaires were carried out, and the results realized in the EU by the independent FBI Economic Department were implemented. On the basis of earlier pilot studies, variants of a successful transformation were implemented, assuming different roles performed by a citizen (entrepreneur). Opportunities to tackle climate change and global challenges have been identified based on innovation and motivation. The opinion on the way of thinking in Poland and Germany was compared, and a descriptive model was prepared to increase the achievement of the assumed goals, together with a model based on innovation. Citizens should be active in efforts to promote renewable energy. The EU has a strong base to work to avoid climate change. What is needed is innovative thinking and a motivation to introduce changes with the involvement of every citizen through solidarity, efficiency, and justice. The existing foundations of legal solutions create adaptation possibilities and the ability to achieve goals through self-discipline, comparing with the assumption of EU civic awareness, significantly affecting the successful implementation of RES. Analyzing the attitudes of Poland and Germany, it seems that the distant social consequences are not sufficient. It is necessary not only to perform selected management functions (planning, organizing), but also partly to motivate. There is a strong need to increase motivation and implement the control process required under the threat of negative consequences in the current period as a key strategic preventive action. The analysis of the opinions of Poland and Germany against the background of the European Union allowed for no significant differences, subject to Germany's readiness to take greater risk. Most of Poland is less inclined to take risks. The lack of an unambiguous opinion may indicate incomplete awareness of both the negative effects of climate change. Both countries are concerned about the unplanned costs of transformation. Germany, unlike Poland, has dedicated employees to handle the climate, and conducts an energy audit and is of interest to investors, thanks to investment plans. [ABSTRACT FROM AUTHOR]