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Number of results: 12
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Abstract

Some data sets contain data clusters not in all dimension, but in subspaces. Known algorithms select attributes and identify clusters in subspaces. The paper presents a novel algorithm for subspace fuzzy clustering. Each data example has fuzzy membership to the cluster. Each cluster is defined in a certainsubspace, but the the membership of the descriptors of the cluster to the subspace (called descriptor weight) is fuzzy (from interval [0,1]) – the descriptors of the cluster can have partial membership to a subspace the cluster is defined in. Thus the clusters are fuzzy defined in their subspaces. The clusters are defined by their centre, fuzziness and weights of descriptors. The clustering algorithm is based on minimizing of criterionfunction. The paper is accompanied by the experimental results of clustering. This approach can be used for partition of input domain in extraction rule base for neuro-fuzzy systems.
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Abstract

The paper presents the operation of two neuro-fuzzy systems of an adaptive type, intended for solving problems of the approximation of multi-variable functions in the domain of real numbers. Neuro-fuzzy systems being a combination of the methodology of artificial neural networks and fuzzy sets operate on the basis of a set of fuzzy rules “if-then”, generated by means of the self-organization of data grouping and the estimation of relations between fuzzy experiment results. The article includes a description of neuro-fuzzy systems by Takaga-Sugeno-Kang (TSK) and Wang-Mendel (WM), and in order to complement the problem in question, a hierarchical structural self-organizing method of teaching a fuzzy network. A multi-layer structure of the systems is a structure analogous to the structure of “classic” neural networks. In its final part the article presents selected areas of application of neuro-fuzzy systems in the field of geodesy and surveying engineering. Numerical examples showing how the systems work concerned: the approximation of functions of several variables to be used as algorithms in the Geographic Information Systems (the approximation of a terrain model), the transformation of coordinates, and the prediction of a time series. The accuracy characteristics of the results obtained have been taken into consideration.
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Abstract

This paper presents the improved version of the classification system for supporting glaucoma diagnosis in ophthalmology. In this paper we propose the new segmentation step based on the support vector clustering algorithm which enables better classification performance.
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Abstract

Clusters belong to the regional innovation system, which led to the formulation and implementation of the cluster-based policy in many countries. The positive impact of clusters on the competitiveness of regions was confirmed by empirical studies. Absence of clusters means retardation in a regional development. The implementation of cluster policy supporting coopetition into the scope of principled regional policy assumptions seems urgent. In this way effective conditions for the formation of growth poles around industries specific for a given region will be developed and, consequently, the economic specialization of individual regions will be achieved. Observation of the benefits resulting from the functioning of clusters in the region, taking into account their possible negative impact, will allow to determine the specificity of regional development policy based on clusters. These problems indicated above are the subject of this study, based on the Polish and foreign literature available on the subject employing the desk research method.
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Abstract

An analysis of the power system functioning and the behaviors of the energy market participants allows the trends taking place within years to be identified, including these associated with the evolution of the electric energy and power demand profiles. The problems of balancing the peak power demand are of both a short and long term nature, which implies the need for changes in the electricity generation sector. Apart from the existing “silo-type” generation units, the construction of distributed energy sources implemented in the civic formula in the framework of self-sufficient energy communes and energy clusters is becoming increasingly important. Support for these programs is realized both at the legislative level, as well as within dedicated competitions and ministerial activities. The financial support carried out by the National Fund for Environmental Protection and Water Management and the Regional Operational Programs is also noticeable. One of the activities aimed at spreading the idea of clustering was the competition for certified energy clusters, conducted by the Ministry of Energy. The goal of the contest was the promotion and development of the distributed energy sector, which could be used for the improvement of energy security in the local manner and constitute a basis for the knowledge necessary in planning and developing the state’s energy policy. The paper presents a synthetic analysis of the results of the competition for a certified energy cluster from the perspective of planning and operational needs related to the functioning of the power system. Further, the information about the investment plans of new generation capacities, including their breakdown with respect to type, achievable power and costs has been provided. Also, the balancing of the demand for electric energy by own generation within the energy clusters has been characterized for three time perspectives
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Abstract

The development of electromobility is a challenge for the power system in both technical and economic-market terms. As of today, there are no analyses to determine the power necessary to supply the planned infrastructure and to estimate the incentives and economic benefits resulting from the modification of the settlement method. The document determining the legal regulations and the obligation to build vehicle charging stations for specific municipalities is the Act on Electromobility and Alternative Fuels. This act estimates that the development of electromobility, due to the specifics including not only individual vehicles, will take place in certain areas. The places which in the first stage will be dedicated to the potential implementation of the concept of electromobility will be municipalities covering large agglomerations. In addition, due to the local aspect, the development of electromobility may take place in the areas of energy clusters’ initiatives, which, using the policy of increasing energy awareness, are aimed at energy production from local renewable energy resources. The planned development of electromobility assumes a systematic increase in the number of electric cars caused by the introduction of support systems. The dynamization of this sector will cause an increase in the demand for electricity. Due to power system reasons, an important factor determining the level of energy consumption depending on the time of day may be an appropriate shape of the pricing for the charging service. Appropriate price list stimulation can affect the behavior of recipients, causing the charging of cars in the off-peak of electricity demand. The aim of the article is to characterize the scale of the phenomenon of electromobility in the context of the emergence of a charging points infrastructure along with the possibility of price-setting stimulation affecting the profile of energy demand. It is also important to consider the challenges and responsibilities of municipalities and energy clusters from the perspective of introducing electromobility.
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Abstract

In spite of technological, logistic and economic difficulties, interest in renewable energy sources in the world is consistently increasing. This trend is also observed in Poland, mainly due to the urgent need to tackle the problem of climate change, which is caused by the increasing concentration of gaseous pollutants in the atmosphere. The paper presents a short script of the issue of estimating renewable energy resources in Poland in the context of creating local low carbon economy plans at the level of municipalities/counties where RES sources should be taken into account. The author proposed an individual approach to estimate the potential of RES, taking the local conditions and the short characteristics of the small and medium companies sector in Poland into account. These companies have a great application potential to increase the share of renewable energies and to improve energy efficiency in their business. The actions, which are taken by the Ministry of Energy in the field of civil energy development, enhancing local energy security and the sustainable development of renewable energy resources support the development of energy clusters covering one district or five municipalities. In the article, the author presents data on the number of companies possessing a concession for generating electricity in RES installations in the power range from 40 kW to 200 kW. These companies can largely be the nucleus for creating a local cluster in which microgrids will be a key element.
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Abstract

Economic development is strictly dependent on access to inexpensive and reliable energy sources based on diversified primary fuels. The strategic framework for the construction of the energy mix is defined in the Energy Policy of the State, the content of which, in terms of its mandatory elements, has been specified in the Energy Law. The task of the Energy Policy of the State is to create the shape of the future power sector, including designing the most advantageous regulatory, system and technical solutions guaranteeing the appropriate level of energy security of the country, monitoring of the system’s evolution and also designing and implementing changes aimed at the optimization of the functioning mechanisms. The vision of the development of the power system at the global level should also reflect changes in the formation of dispersed civil energy structures. Unfortunately, the results of the conducted analyses reveal existing imperfections of the data acquisition and information system, which should be used in the planning process. This issue is particularly important from the perspective of the dynamically developing concept of the energy self-sufficiency of communes and the emergence of energy clusters. The present paper describes the functioning of strategic planning in the field of the electric power system with an illustration of the improperly functioning mechanisms of information transfer in the context of the advancement of dispersed civil energy structures.
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Abstract

Pollution, climate change and energy security are significant problems. Climate-disrupting fossil fuels are being replaced by clean and non-depletable sources of energy. It requires major changes to energy infrastructures and strong support for promotion of the use of energy from renewable sources. Renewable energy is emerging as a driver of inclusive economic growth and reinforcing energy security. Public entities have to promote renewable energy development by implementing cost-effective national support schemes. By acting at national-level, several barriers to public and private investments could be tackled, addressing the lack of coordination between various authorising bodies at national level and stimulatng the administrative capacity to implement energy projects. It should be effective in promoting transparency for investors and others economic operators. In Poland there is a lack of regulatory policies creating incentives for decentralised energy. Market-based support schemes are still needed for small-scale self-consumption system. Currently operating solutions have been shown in the contrast of the ones applied abroad. The development of clean energy technologies depends on many factors. The author identified few most important ones, mainly financial, regulatory issues, social, environmental and characterized them in this work. The article presents the recommendations of regulatory framework and some proposals for energy cluster based policy’s tools, the introduction of which would significantly facilitate the wider renewable energy uses in Poland.
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Abstract

The article deals with the patterns of segmental adaptation of Polish voiceless affricates in initial and fi nal CC (consonant + consonant) clusters by native speakers of English. The data have been collected in an online loanword adaptation experiment in which 30 native speakers of Southern British English reproduced Polish words containing such sequences. The major problem posed by the data is the divergent adaptation of the post-alveolar /͡tʂ/ vs. the pre-palatal /͡tɕ/, with the former substituted mainly with the coronal plosive [t] and the latter realised as the palato-alveolar affricate [͡tʃ]. It is argued that these patterns of nativisation are due to the highlyranked IDENT-IO[dist] constraint, which militates against the modifi cation in the value of the feature [distributed]. Furthermore, it is demonstrated that the experimental results provide evidence in favour of the fundamental assumptions underlying the phonological approach to loan assimilation, namely the phonological input view as well as the faithful perception view.
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Abstract

The same speech sounds (phones) produced by different speakers can sometimes exhibit significant differences. Therefore, it is essential to use algorithms compensating these differences in ASR systems. Speaker clustering is an attractive solution to the compensation problem, as it does not require long utterances or high computational effort at the recognition stage. The report proposes a clustering method based solely on adaptation of UBM model weights. This solution has turned out to be effective even when using a very short utterance. The obtained improvement of frame recognition quality measured by means of frame error rate is over 5%. It is noteworthy that this improvement concerns all vowels, even though the clustering discussed in this report was based only on the phoneme a. This indicates a strong correlation between the articulation of different vowels, which is probably related to the size of the vocal tract.
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Abstract

The article concerns safety of power supply for the final consumers, especially its two comprising elements, which are generation adequacy and distribution system reliability. Generation adequacy has been defined with Loss of Load Probability (LOLP), Loss of Load Expectation (LOLE) and Energy Not Supplied (ENS) indices. Conclusions from generation adequacy forecast prepared by ENSTO-E for Poland compared with other European countries for the years 2020 and 2025 have been discussed along with the resulting threats. Interruptions in energy supply have been characterised by power discontinuity indicator SAIDI. Finally, a reliability and adequacy analysis have been performed for different scenarios of the Polish power system operation in order to assess possibilities of using distributed generation as a backup power source. Based on a simulation model created using the DIgSILENT Power Factory software, the reliability and adequacy calculations have been performed with the probabilistic non-sequential Monte Carlo method and they are followed by a discussion of the obtained results.
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