41 resultados para output-only
Resumo:
In this master’s thesis, wind speeds and directions were modeled with the aim of developing suitable models for hourly, daily, weekly and monthly forecasting. Artificial Neural Networks implemented in MATLAB software were used to perform the forecasts. Three main types of artificial neural network were built, namely: Feed forward neural networks, Jordan Elman neural networks and Cascade forward neural networks. Four sub models of each of these neural networks were also built, corresponding to the four forecast horizons, for both wind speeds and directions. A single neural network topology was used for each of the forecast horizons, regardless of the model type. All the models were then trained with real data of wind speeds and directions collected over a period of two years in the municipal region of Puumala in Finland. Only 70% of the data was used for training, validation and testing of the models, while the second last 15% of the data was presented to the trained models for verification. The model outputs were then compared to the last 15% of the original data, by measuring the mean square errors and sum square errors between them. Based on the results, the feed forward networks returned the lowest generalization errors for hourly, weekly and monthly forecasts of wind speeds; Jordan Elman networks returned the lowest errors when used for forecasting of daily wind speeds. Cascade forward networks gave the lowest errors when used for forecasting daily, weekly and monthly wind directions; Jordan Elman networks returned the lowest errors when used for hourly forecasting. The errors were relatively low during training of the models, but shot up upon simulation with new inputs. In addition, a combination of hyperbolic tangent transfer functions for both hidden and output layers returned better results compared to other combinations of transfer functions. In general, wind speeds were more predictable as compared to wind directions, opening up opportunities for further research into building better models for wind direction forecasting.
Resumo:
Russia inherited a large research and development (R&D) sector from the Soviet times, and has retained a substantial R&D sector today, compared with other emerging economies. However, Russia is falling behind in all indicators measuring innovative output in comparison with most developed countries. Russia’s innovation performance is disappointing, despite the available stock of human capital and overall investment in R&D. The communist legacy still influences the main actors of the innovation system. The federal state is still the most important funding source for R&D. Private companies are not investing in innovative activities, preferring to “import” innovations embedded in foreign technologies. Universities are outsiders in the innovation system, only a few universities carry out research activities. Nowadays, Russia is a resource-depended country. The economy depends on energy and metals for growth. The Russian economy faces the challenge of diversification and should embrace innovation, and shift to a knowledge economy to remain competitive in the long run. Therefore, Russia has to tackle the challenge of developing an efficient innovation system with its huge potential in science expertise and engineering know-how.
Resumo:
In today’s knowledge intense economy the human capital is a source for competitive advantage for organizations. Continuous learning and sharing the knowledge within the organization are important to enhance and utilize this human capital in order to maximize the productivity. The new generation with different views and expectations of work is coming to work life giving its own characteristics on learning and sharing. Work should offer satisfaction so that the new generation employees would commit to organizations. At the same time organizations have to be able to focus on productivity to survive in the competitive market. The objective of this thesis is to construct a theory based framework of productivity, continuous learning and job satisfaction and further examine this framework and its applications in a global organization operating in process industry. Suggestions for future actions are presented for this case organization. The research is a qualitative case study and the empiric material was gathered by personal interviews concluding 15 employee and one supervisor interview. Results showed that more face to face interaction is needed between employees for learning because much of the knowledge of the process is tacit and so difficult to share in other ways. Offering these sharing possibilities can also impact positively to job satisfaction because they will increase the sense of community among employees which was found to be lacking. New employees demand more feedback to improve their learning and confidence. According to the literature continuous learning and job satisfaction have a relative strong relationship on productivity. The employee’s job description in the case organization has moved towards knowledge work due to continuous automation and expansion of the production process. This emphasizes the importance of continuous learning and means that productivity can be seen also from quality perspective. The normal productivity output in the case organization is stable and by focusing on the quality of work by improving continuous learning and job satisfaction the upsets in production can be handled and prevented more effectively. Continuous learning increases also the free human capital input and utilization of it and this can breed output increasing innovations that can increase productivity in long term. Also job satisfaction can increase productivity output in the end because employees will work more efficiently, not doing only the minimum tasks required. Satisfied employees are also found participating more in learning activities.
Resumo:
Laser additive manufacturing (LAM), known also as 3D printing, is a powder bed fusion (PBF) type of additive manufacturing (AM) technology used to manufacture metal parts layer by layer by assist of laser beam. The development of the technology from building just prototype parts to functional parts is due to design flexibility. And also possibility to manufacture tailored and optimised components in terms of performance and strength to weight ratio of final parts. The study of energy and raw material consumption in LAM is essential as it might facilitate the adoption and usage of the technique in manufacturing industries. The objective this thesis was find the impact of LAM on environmental and economic aspects and to conduct life cycle inventory of CNC machining and LAM in terms of energy and raw material consumption at production phases. Literature overview in this thesis include sustainability issues in manufacturing industries with focus on environmental and economic aspects. Also life cycle assessment and its applicability in manufacturing industry were studied. UPLCI-CO2PE! Initiative was identified as mostly applied exiting methodology to conduct LCI analysis in discrete manufacturing process like LAM. Many of the reviewed literature had focused to PBF of polymeric material and only few had considered metallic materials. The studies that had included metallic materials had only measured input and output energy or materials of the process and compared to different AM systems without comparing to any competitive process. Neither did any include effect of process variation when building metallic parts with LAM. Experimental testing were carried out to make dissimilar samples with CNC machining and LAM in this thesis. Test samples were designed to include part complexity and weight reductions. PUMA 2500Y lathe machine was used in the CNC machining whereas a modified research machine representing EOSINT M-series was used for the LAM. The raw material used for making the test pieces were stainless steel 316L bar (CNC machined parts) and stainless steel 316L powder (LAM built parts). An analysis of power, time, and the energy consumed in each of the manufacturing processes on production phase showed that LAM utilises more energy than CNC machining. The high energy consumption was as result of duration of production. Energy consumption profiles in CNC machining showed fluctuations with high and low power ranges. LAM energy usage within specific mode (standby, heating, process, sawing) remained relatively constant through the production. CNC machining was limited in terms of manufacturing freedom as it was not possible to manufacture all the designed sample by machining. And the one which was possible was aided with large amount of material removed as waste. Planning phase in LAM was shorter than in CNC machining as the latter required many preparation steps. Specific energy consumption (SEC) were estimated in LAM based on the practical results and assumed platform utilisation. The estimated platform utilisation showed SEC could reduce when more parts were placed in one build than it was in with the empirical results in this thesis (six parts).
Resumo:
Software is a key component in many of our devices and products that we use every day. Most customers demand not only that their devices should function as expected but also that the software should be of high quality, reliable, fault tolerant, efficient, etc. In short, it is not enough that a calculator gives the correct result of a calculation, we want the result instantly, in the right form, with minimal use of battery, etc. One of the key aspects for succeeding in today's industry is delivering high quality. In most software development projects, high-quality software is achieved by rigorous testing and good quality assurance practices. However, today, customers are asking for these high quality software products at an ever-increasing pace. This leaves the companies with less time for development. Software testing is an expensive activity, because it requires much manual work. Testing, debugging, and verification are estimated to consume 50 to 75 per cent of the total development cost of complex software projects. Further, the most expensive software defects are those which have to be fixed after the product is released. One of the main challenges in software development is reducing the associated cost and time of software testing without sacrificing the quality of the developed software. It is often not enough to only demonstrate that a piece of software is functioning correctly. Usually, many other aspects of the software, such as performance, security, scalability, usability, etc., need also to be verified. Testing these aspects of the software is traditionally referred to as nonfunctional testing. One of the major challenges with non-functional testing is that it is usually carried out at the end of the software development process when most of the functionality is implemented. This is due to the fact that non-functional aspects, such as performance or security, apply to the software as a whole. In this thesis, we study the use of model-based testing. We present approaches to automatically generate tests from behavioral models for solving some of these challenges. We show that model-based testing is not only applicable to functional testing but also to non-functional testing. In its simplest form, performance testing is performed by executing multiple test sequences at once while observing the software in terms of responsiveness and stability, rather than the output. The main contribution of the thesis is a coherent model-based testing approach for testing functional and performance related issues in software systems. We show how we go from system models, expressed in the Unified Modeling Language, to test cases and back to models again. The system requirements are traced throughout the entire testing process. Requirements traceability facilitates finding faults in the design and implementation of the software. In the research field of model-based testing, many new proposed approaches suffer from poor or the lack of tool support. Therefore, the second contribution of this thesis is proper tool support for the proposed approach that is integrated with leading industry tools. We o er independent tools, tools that are integrated with other industry leading tools, and complete tool-chains when necessary. Many model-based testing approaches proposed by the research community suffer from poor empirical validation in an industrial context. In order to demonstrate the applicability of our proposed approach, we apply our research to several systems, including industrial ones.
Resumo:
The human striatum is a heterogeneous structure representing a major part of the dopamine (DA) system’s basal ganglia input and output. Positron emission tomography (PET) is a powerful tool for imaging DA neurotransmission. However, PET measurements suffer from bias caused by the low spatial resolution, especially when imaging small, D2/3 -rich structures such as the ventral striatum (VST). The brain dedicated high-resolution PET scanner, ECAT HRRT (Siemens Medical Solutions, Knoxville, TN, USA) has superior resolution capabilities than its predecessors. In the quantification of striatal D2/3 binding, the in vivo highly selective D2/3 antagonist [11C] raclopride is recognized as a well-validated tracer. The aim of this thesis was to use a traditional test-retest setting to evaluate the feasibility of utilizing the HRRT scanner for exploring not only small brain regions such as the VST but also low density D2/3 areas such as cortex. It was demonstrated that the measurement of striatal D2/3 binding was very reliable, even when studying small brain structures or prolonging the scanning interval. Furthermore, the cortical test-retest parameters displayed good to moderate reproducibility. For the first time in vivo, it was revealed that there are significant divergent rostrocaudal gradients of [11C]raclopride binding in striatal subregions. These results indicate that high-resolution [11C]raclopride PET is very reliable and its improved sensitivity means that it should be possible to detect the often very subtle changes occurring in DA transmission. Another major advantage is the possibility to measure simultaneously striatal and cortical areas. The divergent gradients of D2/3 binding may have functional significance and the average distribution binding could serve as the basis for a future database. Key words: dopamine, PET, HRRT, [11C]raclopride, striatum, VST, gradients, test-retest.
Resumo:
Partial ownership interests are a widespread phenomenon in modern corporate environment. Unless minority shareholding affords the target to exercise control over the target, they do currently not have to be notified to the European Commission under EU merger regime. However, economic research has long suggested that when linking competing or non-horizontally positioned undertakings particularly in industries with few competitors, minority shareholdings even far below the majority of shares or voting rights could lead to higher prices or lower output volumes to the detriment of consumers. The Commission has recognized this issue and proceeded to suggest an extension of the merger regime to catch also certain non-controlling minority acquisitions. Horizontal non-controlling minority shareholdings create a positive correlation between the sales revenues of the partial acquirer and target. Through the equity interest the acquirer will internalise a fraction, proportional to the financial rights attached to the shareholding, of the profit of the target. This will incentivise the acquirer to contribute to increasing the target’s business profits by increasing its own sales price (horizontal unilateral effects). When a minority stake is held in a vertically related or a conglomerate company, the minority acquirer could be allowed to hamper or eliminate the target’s rivals’ access either to inputs (input foreclosure) or customers (customer foreclosure), depending on which level of the supply chain the parties are (vertical unilateral effects). Under certain circumstances minority share acquisitions could also lessen competition because they facilitate collusion between companies active in the market (coordinated effects). Economic theory confirms that non-controlling minority shareholdings may under certain circumstances create anti-competitive effects that are unlikely to be remedies by pro-competitive effects. However, they are likely to be of less significant nature than anticompetitive effects created by full mergers. This derives fore mostly from the fact that a minority share acquirer carries all the costs associated with its unilateral action but will internalise only a fraction of the lost profits. This is likely to limit the acquirer’s incentive to raise price and the profitability of such behavior. Having in mind that the number of potentially problematic cases is expected to be next to negligible, the limited potential competitive effects of non-controlling minority share acquisitions cannot be seen to clearly merit extension of the scope of the EUMR. The system suggested by the Commission is particularly ill-fitted for such purpose given the clear lack of legal certainty and considerable administrative burden associated with it.
Resumo:
This thesis reviews the role of nuclear and conventional power plants in the future energy system. The review is done by utilizing freely accesible publications in addition to generating load duration and ramping curves for Nordic energy system. As the aim of the future energy system is to reduce GHG-emissions and avoid further global warming, the need for flexible power generation increases with the increased share of intermittent renewables. The goal of this thesis is to offer extensive understanding of possibilities and restrictions that nuclear power and conventional power plants have regarding flexible and sustainable generation. As a conclusion, nuclear power is the only technology that is able to provide large scale GHG-free power output variations with good ramping values. Most of the currently operating plants are able to take part in load following as the requirement to do so is already required to be included in the plant design. Load duration and ramping curves produced prove that nuclear power is able to cover most of the annual generation variation and ramping needs in the Nordic energy system. From the conventional power generation methods, only biomass combustion can be considered GHG-free because biomass is considered carbon neutral. CFB combusted biomass has good load follow capabilities in good ramping and turndown ratios. All the other conventional power generation technologies generate GHG-emissions and therefore the use of these technologies should be reduced.
Resumo:
Tämän kandidaatintyön aiheena on D-luokan audiovahvistimen särö ja kohina. Tarkoituksena on selvittää vahvistinluokan merkittävin särö- ja kohinamekanismi, sekä arvioida, voidaanko häiriöitä vähentää lähdön suodattimella. Tutkimusmenetelminä on kirjallisuus ja simulointi. Aineistona on käytetty IEEE:ssä julkaistuja tieteelisiä artikkeleita, eri valmistajien laatimia ohjeita, sekä aihetta käsitteleviä kirjoja. Keskeisimmät tulokset olivat, että merkittävin särömekanismi on transistoreiden suoja-ajan aiheuttama vääristymä, sekä että merkittävin kohina syntyy modulaatiossa käytetystä kantoaallosta. Kantoaallon näkyvyyteen kuormassa voidaan vaikuttaa ulostulon alipäästösuodattimella. Suoja-ajan aiheuttama harmoninen kokonaissärö asettuu musiikin kaistanleveydelle, joten sitä ei voida poistaa suodattamalla.
Resumo:
This study discusses the importance of learning through the process of exporting, and more specifically how such a process can enhance the product innovativeness of a company. The purpose of this study is to investigate the appropriate sources of learning and to suggest an interactive framework for how new knowledge from exporting markets can materialize itself into product innovation. The theoretical background of the study was constructed from academic literature, which is related to concepts of learning by exporting, along with sources for learning in the market and new product development. The empirical research in the form of a qualitative case study was based on four semi-structured interviews and secondary data from the case company official site. The interview data was collected between March and April 2015 from case company employees who directly work in the department of exporting and product development. The method of thematic analysis was used to categorize and interpret the collected data. What was conclusively discovered, was that the knowledge from an exporting market can be an incentive for product innovation, especially an incremental one. Foreign customers and competitors as important sources for new knowledge contribute to the innovative process. Foreign market competitors’ influence on product improvements was high only when the competitor was a market leader or held a colossal market share, while the customers’ influence is always high. Therefore, involving a foreign customer in the development of a new product is vital to a company that is interested in benefiting from what is learned through exporting. The interactive framework, which is based on the theoretical background and findings of the study, suggests that exporting companies can raise their product innovativeness by utilizing newly gained knowledge from exporting markets. Except for input, in the form of sources of learning, and product innovation as an output, the framework contains a process of knowledge transfer, the absorptive capacity of a firm and a new product development process. In addition, the framework and the findings enhance the understanding of the disputed relationship between an exporting experience and product innovation. However, future research is needed in order to fully understand all the elements of the framework, such as the absorptive capacity of a firm as well as more case companies to be processed in order to increase the generalization of the framework
Resumo:
The successful performance of company in the market relates to the quality management of human capital aiming to improve the company's internal performance and external implementation of the core business strategy. Companies with matrix structure focusing on realization and development of innovation and technologies for the uncertain market need to select thoroughly the approach to HR management system. Human resource management has a significant impact on the organization and use a variety of instruments such as corporate information systems to fulfill their functions and objectives. There are three approaches to strategic control management depending on major impact on the major interference in employee decision-making, development of skills and his integration into the business strategy. The mainstream research has focus only on the framework of strategic planning of HR and general productivity of firm, but not on features of organizational structure and corporate software capabilities for human capital. This study tackles the before mentioned challenges, typical for matrix organization, by using the HR control management tools and corporate information system. The detailed analysis of industry producing and selling electromotor and heating equipment in this master thesis provides the opportunity to improve system for HR control and displays its application in the ERP software. The results emphasize the sustainable role of matrix HR input control for creating of independent project teams for matrix structure who are able to respond to various uncertainties of the market and use their skills for improving performance. Corporate information systems can be integrated into input control system by means of output monitoring to regulate and evaluate the processes of teams, using key performance indicators and reporting systems.