991 resultados para Automatic layout generation
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Centrifugal pumps are a notable end-consumer of electrical energy. Typical application of a centrifugal pump is the filling or emptying of a reservoir tank, where the pump is often operated at a constant speed until the process is completed. Installing a frequency converter to control the motor substitutes the traditional fixed-speed pumping system, allows the optimization of rotational speed profile for the pumping tasks and enables the estimation of rotational speed and shaft torque of an induction motor without any additional measurements from the motor shaft. Utilization of variable-speed operation provides the possibility to decrease the overall energy consumption of the pumping task. The static head of the pumping process may change during the pumping task. In such systems, the minimum rotational speed changes during reservoir filling or emptying, and the minimum energy consumption can’t be achieved with a fixed rotational speed. This thesis presents embedded algorithms to automatically identify, optimize and monitor pumping processes between supply and destination reservoirs, and evaluates the changing static head –based optimization method.
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The general trend towards increasing e ciency and energy density drives the industry to high-speed technologies. Active Magnetic Bearings (AMBs) are one of the technologies that allow contactless support of a rotating body. Theoretically, there are no limitations on the rotational speed. The absence of friction, low maintenance cost, micrometer precision, and programmable sti ness have made AMBs a viable choice for highdemanding applications. Along with the advances in power electronics, such as signi cantly improved reliability and cost, AMB systems have gained a wide adoption in the industry. The AMB system is a complex, open-loop unstable system with multiple inputs and outputs. For normal operation, such a system requires a feedback control. To meet the high demands for performance and robustness, model-based control techniques should be applied. These techniques require an accurate plant model description and uncertainty estimations. The advanced control methods require more e ort at the commissioning stage. In this work, a methodology is developed for an automatic commissioning of a subcritical, rigid gas blower machine. The commissioning process includes open-loop tuning of separate parts such as sensors and actuators. The next step is to apply a system identi cation procedure to obtain a model for the controller synthesis. Finally, a robust model-based controller is synthesized and experimentally evaluated in the full operating range of the system. The commissioning procedure is developed by applying only the system components available and a priori knowledge without any additional hardware. Thus, the work provides an intelligent system with a self-diagnostics feature and an automatic commissioning.
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Ride comfort of elevators is one of the quality criteria valued by customers. The objective of this master’s thesis was to develop a process to measure the ride comfort of automatic elevator doors. The door’s operational noise was chosen as a focus area and other kinds of noise for example caused by pressure differences in the elevator shaft were excluded. The thesis includes a theory part and an empirical part. In the first part theories of quality management, measuring of quality and acoustics are presented. In the empirical part the developed ride comfort measuring process is presented, different operational noise sources are analyzed and an example is presented of how this measuring process can be used to guide product development. To measure ride comfort a process was developed where a two-room silent room was used as a measuring environment and EVA-625 device was used in the actual measuring of door noise. A-weighted decibels were used to scale noise pressure levels and the door movement was monitored with an accelerometer. This enabled the connection between the noise and noise sources which in turn helped to find potential ride comfort improvement ideas. The noise isolation class was also measured with the Ivie-measuring system. Measuring of door ride comfort gives feedback to product development and to managing current product portfolio. Measuring enables the continuous improvement of elevator door ride comfort. The measuring results can also be used to back up marketing arguments for doors.
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Today the limitedness of fossil fuel resources is clearly realized. For this reason there is a strong focus throughout the world on shifting from fossil fuel based energy system to biofuel based energy system. In this respect Finland with its proven excellent forestry capabilities has a great potential to accomplish this goal. It is regarded that one of the most efficient ways of wood biomass utilization is to use it as a feedstock for fast pyrolysis process. By means of this process solid biomass is converted into liquid fuel called bio-oil which can be burnt at power plants, used for hydrogen generation through a catalytic steam reforming process and as a source of valuable chemical compounds. Nowadays different configurations of this process have found their applications in several pilot plants worldwide. However the circulating fluidized bed configuration is regarded as the one with the highest potential to be commercialized. In the current Master’s Thesis a feasibility study of circulating fluidized bed fast pyrolysis process utilizing Scots pine logs as a raw material was conducted. The production capacity of the process is 100 000 tonne/year of bio-oil. The feasibility study is divided into two phases: a process design phase and economic feasibility analysis phase. The process design phase consists of mass and heat balance calculations, equipment sizing, estimation of pressure drops in the pipelines and development of plant layout. This phase resulted in creation of process flow diagrams, equipment list and Microsoft Excel spreadsheet that calculates the process mass and heat balances depending on the bio-oil production capacity which can be set by a user. These documents are presented in the current report as appendices. In the economic feasibility analysis phase there were at first calculated investment and operating costs of the process. Then using these costs there was calculated the price of bio-oil which is required to reach the values of internal rate of return of 5%, 10%, 20%, 30%, 40%, and 50%.
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At present stage the analytical design of wave tolerance for floating structures and vessels is still imperfect due to the mutually complex and nonlinear phenomena between structures and waves. Wave tolerance design is usually carried out through iterative evaluations of results from model tests in a wave basin, and this is done in order to reach a final structural design. The wave generation has then become an important technology in the field of the coastal and ocean engineering. This paper summarizes the facilities of a test basin and a wave maker in Japan and also surveys the methodology of the generation of ocean waves in a test basin.
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This paper discusses the effect of tool wear on surface finish in single-point diamond turning of single crystal silicon. The morphology and topography of the machined surface clearly show the type of cutting edge wear reproduced onto the cutting grooves. Scanning electron microscopy is used in order to correlate the cutting edge damage and microtopography features observed through atomic force microscopy. The possible wear mechanisms affecting tool performance and surface generation during cutting are also discussed. The zero degree rake angle single point diamond tool presented small nicks on the cutting edge. The negative rake angle tools presented more a type of crater wear on the rake face. No wear was detected on flank face of the diamond tools.
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Presentation at the Nordic Perspectives on Open Access and Open Science seminar, Helsinki, October 15, 2013
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Kristiina Hormia-Poutasen esitys CBUC-konferenssissa Barcelonassa 12.4.2013.
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Kristiina Hormia-Poutasen esitys CBUC-konferenssissa Barcelonassa 12.4.2013.
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Kristiina Hormia-Poutasen esitys CBUC-konferenssissa Barcelonassa 12.4.2013.
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Kristiina Hormia-Poutasen esitys CBUC-konferenssissa 12.4.2013 Barcelonassa.
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New challenges have been created in the modern work environment as the diversity of the workforce is greater than ever in terms of generations. There will become a large demand of generation Y employees as the baby boomer generation employees retire at an accelerated rate. The purpose of this study is to investigate Y generation specific characteristics and to identify motivational systems to enhance performance. The research questions are: 1. What are Y generation characteristics? 2. What motivational systems organizations can form to motivate Y generation employees and in turn, create better performance? The Y generation specific characteristics identified from the literature include; achievement oriented; confident; educated; multitasking; having a need for feedback; needing management support; sociable and tech savvy. The proposed motivational systems can be found in four areas of the organization; HRM, training and development, communication and decision making policies. Three focus groups were held to investigate what would motivate generation Y employees to achieve better performance. Two of these focus groups were Finnish natives and the third consisted of international students. The HRM systems included flexibility and a culture of fun. It was concluded that flexibility within the workplace and role was a great source of motivation. Culture of fun was not responded to as favorably although most focus group participants rated enjoyableness as one of their top motivating factors. Training and development systems include training programs and mentoring as sources of potential motivation. Training programs were viewed as a mode to gain a better position and were not necessarily seen as motivational systems. Mentoring programs were not concluded to have a significant effect on motivation. Communication systems included keeping up with technology, clarity and goals as well as feedback. Keeping up with technology was seen as an ineffective tool to motivate. Clarity and goal setting was seen as very important to be able to perform but not necessarily motivating. Feedback had a highly motivating effect on these focus groups. Decision making policies included collaboration and teamwork as well as ownership. Teams were familiar and meet the social needs of Y generation employees and are motivating. Ownership was equated with trust and responsibility and was highly valued as well as motivating to these focus group participants.
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Innovations diffuse at different speed among the members of a social system through various communication channels. The group of early adopters can be seen as the most influential reference group for majority of people to base their innovation adoption decisions on. Thus, the early adopters can often accelerate the diffusion of innovations. The purpose of this research is to discover means of diffusion for an innovative product in Finnish market through the influential early adopters in respect to the characteristics of the case product. The purpose of the research can be achieved through the following sub objectives: Who are the potential early adopters for the case product and why? How the potential early adopters of the case product should be communicated with? What would be the expectations, preferences, and experiences of the early adopters of the case product? The case product examined in this research is a new board game called Rock Science which is considered to be incremental innovation bringing board gaming and hard rock music together in a new way. The research was conducted in two different parts using both qualitative and quantitative research methods. This mixed method research began with expert interviews of six music industry experts. The information gathered from the interviews enabled researcher to compose the questionnaire for the quantitative part of the study. Internet survey that was sent out resulted with a sample of 97 responses from the targeted population. The key findings of the study suggest that (1) the potential early adopters for the case product are more likely to be young adults from the capital city area with great interest in rock music, (2) the early adopters can be reached effectively through credible online sources of information, and (3) the respondents overall product feedback is highly positive, except in the case of quality-price ratio of the product. This research indicates that more effective diffusion of Rock Science board game in Finland can be reached through (1) strategic alliances with music industry and media partnerships, (2) pricing adjustments, (3) use of supporting game formats, and (4) innovative use of various social media channels.
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Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014