Oxy-fuel combustion (OFC) belongs to one of the three commonly known clean coal technologies for power generation sector and other industry sectors responsible for CO2emissions (e.g., steel or cement production). The OFC capture technology is based on using high-purity oxygen in the combustion process instead of atmospheric air. Therefore flue gases have a high concentration of CO2- Due to the limited adiabatic temperature of combustion some part of CO2must be recycled to the boiler in order to maintain a proper flame temperature. An integrated oxy-fuel combustion power plant constitutes a system consisting of the following technological modules: boiler, steam cycle, air separation unit, cooling water and water treatment system, flue gas quality control system and CO2processing unit. Due to the interconnections between technological modules, energy, exergy and ecological analyses require a system approach. The paper present the system approach based on the 'input-output' method to the analysis of the: direct energy and material consumption, cumulative energy and exergy consumption, system (local and cumulative) exergy losses, and thermoecological cost. Other measures like cumulative degree of perfection or index of sustainable development are also proposed. The paper presents a complex example of the system analysis (from direct energy consumption to thermoecological cost) of an advanced integrated OFC power plant.
One of the main human goals is to achieve the state of happiness. Almost all people ask themselves the question of how to attain this goal. For thousands of years, philosophers and spiritual leaders and, nowadays, researchers representing various disciplines of social sciences, have been searching for the right answer to this question. One of the dilemmas intertwined in the debate about the essence of happiness relates to the tension expressed by the question “to be or to have”; the tension between the spiritual and the material world; between sacrum and profanum. Can accumulation of money and material possessions make us happy? Starting with the message passed on by a German psychoanalyst Erich Fromm in his essay “To Have or to Be” and the wisdom derived from the classic philosophical and religious works, I will attempt to define the relation between the state of happiness and the attachment to money and possessions or the attachment to social and transcendent values. This difficult, yet crucial, problem will be analyzed in the context of the current psychological knowledge related to the emotional and cognitive consequences of taking a materialistic approach to life. Erich Fromm and other thinkers who had lived hundreds of years before him, suggested that greed and pursuit of material possessions did not appease the human longing for happiness. The latest experimental research, conducted by psychologists, economists and scholars representing other disciplines of science, seem to strongly confirm these assumptions.
The article is an attempt to collate and present the existing works of Polish geographers who focused on public space in cities, taking two main theoretical and methodological approaches – objective and subjective – under consideration. The article discusses different definitions of the analysed term in an interdisciplinary context as well as indicates main aspects and research directions in geographical studies along with the scholars representing them. Moreover, the authors make an attempt to evaluate the existing state of the art and try to set future perspectives for geographical studies on public space in cities. The article finishes with the authors’ conclusions regarding the necessity to continue the research on public space and the role Polish geographers shall play in it.
Marine governance is an essential way of achieving the objectives of sustainable development. It ought to be understood as the process of planning, as well as decision-making and management at the national and regional levels taking into account the global ocean as an ecological unity. The process of decision-making is closely interrelated with the regional and transnational cross-border cooperation. The adoption of the EU Directive establishing a framework for maritime spatial planning (hereinafter: MSP Directive) plays an important role in developing of marine spatial planning in Europe by promoting MSP instruments. MSP Directive requires all coastal EU Member States to prepare cross-sectoral maritime spatial plans by 2021. The development of spatial plans for Polish marine areas was started in 2013. The MSP legal bases are included in the Marine Areas of the Republic of Poland and Maritime Administration Act of 1991 amended in 2015 and its implementing regulations.
In an effort to achieve an optimal availability time of induction motors via fault probabilities reduction and improved prediction or diagnostic tools responsiveness, a conditional probabilistic approach was used. So, a Bayesian network (BN) has been developed in this paper. The objective will be to prioritize predictive and corrective maintenance actions based on the definition of the most probable fault elements and to see how they serve as a foundation for the decision framework. We have explored the causes of faults for an induction motor. The influence of different power ranges and the criticality of the electric induction motor are also discussed. With regard to the problem of induction motor faults monitoring and diagnostics, each technique developed in the literature concerns one or two faults. The model developed, through its unique structure, is valid for all faults and all situations. Application of the proposed approach to some machines shows promising results on the practical side. The model developed uses factual information (causes and effects) that is easy to identify, since it is best known to the operator. After that comes an investigation into the causal links and the definition of the a priori probabilities. The presented application of Bayesian networks is the first of its kind to predict faults of induction motors. Following the results of the inference obtained, prioritizations of the actions can be carried out.