Solar Power Station Output Inverter Control Design

The photovoltaic applications spreads in these days fast, therefore they also undergo great development. Because the amount of the energy obtained from the panel depends on the surrounding conditions, as intensity of the sun exposure or the temperature of the solar array, the converter must be connected to the panel output. The Solar system equipped with inverter can supply small loads like notebooks, mobile chargers etc. in the places where the supplying network is not present. Or the system can be used as a generator and it shall deliver energy to the supply network. Each type of the application has different requirements on the converter and its control algorithm. But for all of them the one thing is common – the maximal efficiency. The paper focuses on design and simulation of the low power inverter that acts as output part of the whole converter. In the paper the design of the control algorithm of the inverter for both types of inverter application – for islanding mode and for operation on the supply grid – is discussed. Attention is also paid to the design of the output filter that should reduce negative side effects of the converter on the supply network

Mathematical Model of Induction Motor with Ferromagnetic Rotor

Results of theoretical and experimentalresearch as well as outcome of simulation by means of theestablished mathematical model of induction motor withferromagnetic rotor in static and transient states arepresented and analyzed

Induction Motor Design by Use of Genetic Optimization Algorithms

The problem of the automated calculationand optimal design of an induction motor is presented . Theproblem of optimization by use of genetic algorithms is setand solved. The analysis of the obtained results is executed

Induction Motor Optimal Design by Use of Cartesian Product

The problem of the automated calculationand optimal design of an induction motor is presented.Given and decided tasks of optimization by use of Cartesianproduct are introduced. The analysis of the obtained resultsis made

Calculating all elements of minimal index in the infinite parametric family of simplest quartic fields

summary:It is a classical problem in algebraic number theory to decide if a number field is monogeneous, that is if it admits power integral bases. It is especially interesting to consider this question in an infinite parametric family of number fields. In this paper we consider the infinite parametric family of simplest quartic fields $K$ generated by a root $\xi$ of the polynomial $P_t(x)=x^4-tx^3-6x^2+tx+1$, assuming that $t>0$, $t\neq 3$ and $t^2+16$ has no odd square factors. In addition to generators of power integral bases we also calculate the minimal index and all elements of minimal index in all fields in this family

External End Users and Firm Innovation Performance

Research about users as a source of innovation has been largely restricted to case studies exploring specific innovation projects at the firm level. This study assesses empirically the relationship between external end users' knowledge as an input factor to innovation and firms' innovation success. The results strongly support the hypotheses: (i) that external end users have the potential to essentially improve the innovative performance of firms; (ii) that the technique of interaction during the innovation process and the characteristics of involved external users matter as well. The more firms make use of emphatic design and select specific users to acquire hard-to-articulate customer needs, the stronger is the relationship between access to external end users' knowledge and firm innovation success measured in sales of innovative products

30 years of collaboration

We highlight some of the most important cornerstones of the long standing and very fruitful collaboration of the Austrian Diophantine Number Theory research group and the Number Theory and Cryptography School of Debrecen. However, we do not plan to be complete in any sense but give some interesting data and selected results that we find particularly nice. At the end we focus on two topics in more details, namely a problem that origins from a conjecture of Rényi and Erdős (on the number of terms of the square of a polynomial) and another one that origins from a question of Zelinsky (on the unit sum number problem). This paper evolved from a plenary invited talk that the authors gaveat the Joint Austrian-Hungarian Mathematical Conference 2015, August 25-27, 2015 in Győr (Hungary)

Customer Interaction and Innovation in Hybrid Offerings:Investigating Moderation and Mediation Effects for Goods and Services Innovation

Hybrid offerings are bundles of goods and services offerings provided by the same firm. Bundling value offerings affects how firms innovate, interact with customers, and customize their goods and services. However, it remains unclear how customer interaction might drive the innovation performance of various bundled components. Therefore, this study investigates the effects of customer interactions and service customization on both goods and services innovations in a hybrid offering context, using a unique data set of 146 information technology and manufacturing firms. Customer interaction appears beneficial to both goods and services innovation in a hybrid offerings context, but service customization has different direct effects on goods versus services innovation. As a potential mediator, customer knowledge mobilization resources exert different effects on the goods and services elements of hybrid offerings. Furthermore, for high-interaction customers, medium levels of technical modularity lead to most favorable innovation outcomes for services innovation. The results thus suggest that providers of hybrid offerings should foster customer interactions, to drive the innovation performance of the good and service components, while still making sure to implement service customization strategies. These findings have notable implications for service innovation research

Embracing open innovation to acquire external ideas and technologies and to transfer internal ideas and technologies outside

The objective of this dissertation is to increase understanding of how organizations can embrace open innovation in order to acquire external ideas and technologies from outside the organization, and to transfer internal ideas and technologies to outside the organization. The objective encompasses six sub-objectives, each addressed in one or more substudies. Altogether, the dissertation consists of nine substudies and a compendium summarizing the substudies. An extensive literature review was conducted on open innovation and crowdsourcing literature (substudies 1–4). In the subsequent empirical substudies, both qualitative research methods (substudies 5–7) and quantitative research methods (substudies 8–9) were applied. The four literature review substudies provided insights on the body of knowledge on open innovation and crowdsourcing. These substudies unveiled most of the influential articles, authors, and journals of open innovation and crowdsourcing disciplines. Moreover, they identified research gaps in the current literature. The empirical substudies offer several insightful findings. Substudy 5 shows how non-core ideas and technologies of a large firm can become valuable, especially for small firms. Intermediary platforms can find solutions to many pressing problems of large organizations by engaging renowned scientists from all over world (substudy 6). Intermediary platforms can also bring breakthrough innovations with novel mechanisms (substudy 7). Large firms are not only able to garner ideas by engaging their customers through crowdsourcing but they can also build long-lasting relations with their customers (substudies 8 and 9). Embracing open innovation brings challenges for firms too. Firms need to change their organizational structures in order to be able to fully benefit from open innovation. When crowdsourcing is successful, it produces a very large number of new ideas. This has the consequence that firms need to allocate a significant amount of resources in order to identify the most promising ideas. In an idea contest, customarily, only one or a few best ideas are rewarded (substudy 7). Sometimes, no reward is provided for the selected idea (substudies 8 and 9). Most of the ideas that are received are not implemented in practice