1,485 research outputs found

    Ecological restoration activities for long-term preservation of the alpine and sub-alpine habitats in the Retezat National Park

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    This paper is focusing on the mountain pines (Pinus mugo), the juniper (Juniperus communis) and the rhododendron (Rhododendron kotschyi) common habitats, the establishing the methods of maintaining or protecting of non-degraded populations, and the restoration methods of degraded populations, within the alpine habitats conservative management belonging to the Retezat National Park.. Between the natural and artificial regeneration methods applicable to restore the degraded mountain pines populations, the regeneration by plantation seems to be the only reasonable method, having in view that the natural regeneration is difficult and require long period of time. This study begins with presentation of the preservation plans of the unique natural landscape, named Retezat National Park, located in Meridional Carpathians (Romanian Southern Carpathians) and continues with the description of the natural distribution of the mountain pines (Pinus mugo) populations and their associated herbaceous and woody species in the Retezat National Park. The renaturation with mountain pines seedlings, within the case study regarding an ecological restoration in Retezat National Park, methods, remarks and predictable results are presented. Also, the study offers details concerning the ecological principles of the destroyed habitat’s artificial regeneration, such as: the planted area, seedlings, seedling production and their transportation to the planting area and effective plantation

    Complaint analysis using 8D method within the companies in the filed of automotive

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    The eight disciplines (8D – Eight Disciplines of Problem Solving) model is a problem solving approach typically employed by quality engineers or other professionals and commonly used by the automotive industry. It is a meticulous process used to solve complex problems and its purpose is to identify, correct, and eliminate recurring problems, and it is useful in product and process improvement. The 8D is a method of analysis that after the detection of an irregularity, identifies and seeks the methods of solving and preventing nonconformity. It is a highly disciplined and effective scientific approach for resolving recurring problems and provides excellent guidelines to identify the root cause of the problem, implement containment actions, develop and then implement corrective actions and preventive actions that make the problem go away permanently. Therefore, the Eight Disciplines of Problem Solving (8D) is a problem-solving tool used usually in response to the removal parameters or known product specifications set by customers and incorporates all the important aspects of problem solving: problem description, root cause analysis, correcting the problem and preventing the problem. The approach establishes a permanent corrective action based on statistical analysis of the problem and focuses on the origin of the problem by determining its root causes. Although it originally comprised eight stages, or disciplines, it was later augmented by an initial planning stage. The 8D method application will result in improved products and processes is structured into eight disciplines, focusing on the synergy of the team. This is a popular method for problem solving because it is reasonably easy to teach and effective

    Short introspections regarding the sawdust briquetting as sustainable solution for the environment

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    Wood pellets have only become an important part of this boom in the past few years. Owners of large coal-fired power stations in Europe started searching for a way to fulfill the new regulations and to find a solution for the declining economic relevance of traditional coal-fired power stations due to their high carbon dioxide emissions. The answer was to give the old dirty giants a green coat of paint by “co-firing” regular coal power plants with wood pellets. Wood pellets have similar burning qualities to traditional coal and the costs of converting boilers to burn wood pellets are low. The idea of declaring wood pellets as a carbon neutral energy source was based on the assumption that the released emissions of carbon dioxide during the burning process are neutralized by the carbon that is captured and stored in newly growing trees. The idea of using wood as a renewable source was backed by environment organizations. More recent pellet investment projects as well as facilities currently under construction show that the production of wood pellets is being outsourced by the energy firms to companies specialized in wood pellet production. These firms are 100-percent focused on sourcing the raw material, operating the wood pellet production plant and handling the logistics for transporting the renewable resource

    Study on Deformation Behavior of Non–Hardenable Austenitic Stainless Steel (Grade X5CrNi18–10) by Hot Torsion Tests

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    The steel’s deformation resistance, in which high strain rates have an important influence on the mechanism of failure, might be obtained from a suitably instrumented torsion test. Determination of stainless steel deformability by hot torsion test is the only method that allows obtaining large deformations along the length of the test specimen, so it is mainly used to determine the characteristics at large plastic deformations. By this method, the hot deformability of stainless steel is determined by subjecting to hot torsion the cylindrical stainless steel specimens maintained at the deformation temperature in a tubular oven belonging to the Laboratory of Metal Rolling and Plastic Deformation, at the Faculty of Engineering – Hunedoara, University Politehnica Timişoara. For the experimental hot torsion tests, several stainless steel grades were used and included in a large series of studies destined to determining the deformation behavior of steel. Having in view the previous results obtained in the study of deformability characteristics of two stainless steels (hardenable martensitic stainless steel, grade X46Cr13 and non–hardenable ferritic stainless steel, grade X6Cr17), this paper includes the results of the hot torsion tests conducted to find the deformation behavior of the non–hardenable austenitic stainless steel (grade X5CrNi18–10). For analysis of laboratory hot torsion tests results the univariate and multivariate regression analysis was used, estimating the relationships among the hot–testing temperature, torque moment and number of torsions up to the breaking point of the specimens of austenitic stainless steel. Therefore, the optimum range of heating temperatures applied for deforming the studied steels results clearly from the deformability – temperature (plasticity – temperature and deformation resistance – temperature) diagrams. Correlations are useful because they can indicate a predictive relationship that can be exploited in the laboratory or industrial practice

    Complaint Analysis Using 8D Method within the Companies in the Field of Automotive

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    The eight disciplines (8D – Eight Disciplines of Problem Solving) model is a problem solving approach typically employed by quality engineers or other professionals and commonly used by the automotive industry. It is a meticulous process used to solve complex problems and its purpose is to identify, correct, and eliminate recurring problems, and it is useful in product and process improvement. The 8D is a method of analysis that after the detection of an irregularity, identifies and seeks the methods of solving and preventing nonconformity. It is a highly disciplined and effective scientific approach for resolving recurring problems and provides excellent guidelines to identify the root cause of the problem, implement containment actions, develop and then implement corrective actions and preventive actions that make the problem go away permanently. Therefore, the Eight Disciplines of Problem Solving (8D) is a problem-solving tool used usually in response to the removal parameters or known product specifications set by customers and incorporates all the important aspects of problem solving: problem description, root cause analysis, correcting the problem and preventing the problem. The approach establishes a permanent corrective action based on statistical analysis of the problem and focuses on the origin of the problem by determining its root causes. Although it originally comprised eight stages, or disciplines, it was later augmented by an initial planning stage. The 8D method application will result in improved products and processes is structured into eight disciplines, focusing on the synergy of the team. This is a popular method for problem solving because it is reasonably easy to teach and effective

    Short introspections regarding the sawdust briquetting as sustainable solution for the environment

    Get PDF
    Wood pellets have only become an important part of this boom in the past few years. Owners of large coal-fired power stations in Europe started searching for a way to fulfill the new regulations and to find a solution for the declining economic relevance of traditional coal-fired power stations due to their high carbon dioxide emissions. The answer was to give the old dirty giants a green coat of paint by “co-firing” regular coal power plants with wood pellets. Wood pellets have similar burning qualities to traditional coal and the costs of converting boilers to burn wood pellets are low. The idea of declaring wood pellets as a carbon neutral energy source was based on the assumption that the released emissions of carbon dioxide during the burning process are neutralized by the carbon that is captured and stored in newly growing trees. The idea of using wood as a renewable source was backed by environment organizations. More recent pellet investment projects as well as facilities currently under construction show that the production of wood pellets is being outsourced by the energy firms to companies specialized in wood pellet production. These firms are 100-percent focused on sourcing the raw material, operating the wood pellet production plant and handling the logistics for transporting the renewable resource

    Verification of bernoulli law using the software autodesk simulation cfd

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    Using Fluid Dynamics Analysis (CFD) provides the opportunity to achieve a faster and more thorough study of fluid flow processes and is an important step to obtain information that cannot be obtained otherwise. The finite element method is generally more accurate than the finite volume method, but finite volume method can achieve more accurate mass balances using the balance sheet continuity per volume control. Finite volume method is more appropriate when fluid transport, while the finite element method is used more in the calculations of tension or conduction, which satisfies local continuity condition, is of less importance. Fluid Dynamics Analysis (CFD) is used in numerical analyzes, based on a set of mathematical expressions on linear complex equations defining fundamental fluid flow and heat transfer. This paper presents the simulation of air flow through a tube of special construction in interpreting the law of Bernoulli energy. Laboratory systems are shown, respectively simulating the actual fluid flow

    Biomass from Wood Processing Industries as an Economically Viable and Environmentally Friendly Solution

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    Biomass is seen as an economically viable and environmentally friendly solution to energy generation. Biomass is a financially viable investment as well as being environmentally friendly. The development and implementation of biomass technologies could bring many environmental, energetically and economic benefits, solving important problems such as waste disposal and renewable energy supply. The different countries clearly have chosen very different approaches in developing and deploying various bio–energy options. Partly this is caused by the natural conditions (type of resources and crops, climate) and the structure of the energy system, and also by the specific political priorities linked to the agricultural and forestry sectors in those countries. Romania has a significant potential in organic waste, including waste generated in forestry sector, agro–food industry or municipal biodegradable wastes. Biomass is an emerging renewable fuel that can help to heat homes and buildings at lower impact to the environment and lower costs than fossil fuels. The fuel (usually in the form of biomass pellets) is made from sustainable materials, such as wood, which is easily replaced and in abundance, at a relatively cheap price. As people are becoming more and more conscious about their individual impact on the environment and looking into greener, more efficient alternatives, biomass is slowly becoming one of the nation’s favorite renewable heat technologies. Actually, sawdust as by–product from wood sawing process, doesn’t have much application because of its low burning efficient. However, by pressing the saw dust into pellets, it becomes a kind of high quality biofuel product – sawdust pellets or wood pellets

    Smart Materials Technology-Based Products Applications in the Automotive Industry

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    The developments of new and innovative materials are contributing significantly to the large scale such as automotive industry. Century by century uncountable inventions and developments were dedicated to synchronized technological advancement. Smart materials are highly efficient materials and their performance comes at high costs associated with the high level of R&D involved. Therefore, invention of these materials conceptualized to produce effective sensors and actuators according to the purpose. Some everyday items are already incorporating such smart materials, and the number of applications for them is growing steadily. Invention of functional and intelligent materials introduced new concept of intelligent infrastructure systems, autonomous systems, smart structures and robotics in the bygone years. Smart materials include the piezoelectric materials (PZT)

    Laboratory assembly for analysis of fuel injection systems in the modern internal combustion engines

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    The complexity of the processes taking place in a system of fuel injection management for an internal combustion engine requires extra effort for a proper understanding of the operating principles. This paper is intended to be an intuitive practical application able to simulate the complex electronic control of injection, through a PC and specialized software. The application provides an intuitive and friendly analysis of the processes occurring during the operation of an injection computer. Moreover, the system allows the determination of the gasoline amount injected by the various types of fuel injectors, in a certain period of time and at different pressures of the fuel, depending on the load, speed and thermal regime of the engine. The laboratory assembly for a fuel injection system is intended as an experimental stand with exclusive didactical applicability. We want to observe the main characteristics of a fuel feeding and injection system, as the identification of components for the control system, data acquisition system and fuel injection system, the analysis of the different types of signals that can be used to actuate the injectors, the establishing the principles of injector operation in accordance with the control electronics, the visualization of the injection cadence and amount injected, depending on the engine speed and load, the programming of injection computers etc
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