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speeds and autonomously control both active and reactive power, outperforming traditional generators. However, challenges arise when integrating such wind farms with the grid, manifesting as voltage stability issues and grid disturbances. These stem from DFIG's inadequate terminal voltage and frequency regulation, primarily due to insufficient excitation and resulting reactive power shortages. Therefore, enhancing terminal voltage and frequency generation is imperative. In this study, we aim to boost DFIG's performance by augmenting its reactive power through STATCOM, addressing supply voltage and frequency reductions caused by varying loads. Additionally, a neuro-fuzzy logic controller is employed to regulate generated voltage and frequency within the dynamic DFIG-STATCOM-load model, simulated using MATLAB/SIMULINK.
presented. In particular, the difficulty of meeting the repair criterion |D-D'| was pointed out using the current measurement method. The article also illustrates the original measurement method proposed by author, which is a reference measurement for currently used methods, along with its limitations.
concept. Then, the information was gathered to present the lodzkie region in the area of R&D and economy. The last (empirical) part was the study in the form of workshops being organized to obtain information on factors influencing the implementation of RRI concept. Findings: Implementing RRI approach encounters barriers, in particular, the idea needs wider popularization, especially in terms of the benefits of its application. There is also insufficient social trust in science. This emphasizes a need to promote reliable scientific knowledge and to strengthen social awareness of its role in the development of the world. The role of internal and external stakeholders is important here. Communication between participants in innovation processes can improve the efficiency of activity in the sphere of RRI, including mechanisms of inclusive decision-making. The channels and models of communication have to take into consideration the heterogeneity of the recipients. This requires human resources with relevant competencies to execute efficient communication patterns. Research limitations/implications: The workshop was conducted on a relatively small sample and the attendants were already involved in socially/economically/environmentally responsible activity. Although it was possible to capture the main ideas on how to foster RRI concept, it is important to execute wider research on a sample representative for a whole quadruple helix population, including scientists not yet interested in “responsible science”. Practical implications: Findings are important for entities interested in promoting responsible research, e.g. public (e.g. regional) bodies. Social implications: A better understanding of the factors influencing RRI concept implementation can result in fostering the process which in turn would be beneficial for the society as RRI concept promotes research oriented on public interest. Originality/value: The paper presents publicly important findings that (with awareness of their limitations) can entail a commitment to achieving sustainable, ethically acceptable, and socially desirable results of research conducted within universities.
of a master's thesis awarded by IPMA Poland. This is also a continuation of another article published in this journal1 . In general, the whole research was based on a mixed-methods approach, combining quantitative and qualitative methods. A sequential explanatory strategy was employed, allowing for the collection of quantitative data, followed by enrichment with qualitative data for a more in-depth interpretation. This article is about the description of qualitative research, recommendations are written on the basis of full mixed research. Findings: For constructing teams in R&D projects, recommendations were made: 1) Strive for gender balance in the team, 2) Create teams with a small number of members, 3) Pay attention to the subject matter expertise and experience of the potential leader when forming the team, 4) Introduce a selection process for team members in which the project leader, the project initiator and the group of project initiators have a stake, 5) Value the work of team members and their contributions, regardless of their role in the project, 6) Focus on motivating team members through career development, research curiosity, and the opportunity to collaborate with other scientists, 7) Provide clear rules for project collaboration and accountability, 8) Ensure integration and adequate communication of the team, 9) Support effective management of R&D projects, 10) Monitor and resolve problems within the team. Avoid the occurrence of negative roles and create an environment where team members feel supported and valued. Research limitations/implications: The article's limitation lies in the potential omission of advanced dependencies from related management fields - from psychology, sociology, or administration. Practical implications: The research indicates recommendations for the practice of managing research and development projects. Implementing these recommendations may contribute to improving the results of R&D teams.Originality/value: Filling a research gap on the construction of contemporary research and development teams. Discoveries regarding leader selection, researcher motivation, and the impact of various factors on team performance have significant implications for the practice of managing R&D projects. They are addressed to all individuals involved in research and development activities.
especially those using in it the so-called comb of Dirac deltas. The latter ones do not lead to getting a correct formula for the spectrum of the output waveform of an A/D converter, or they yield no formula at all. Using the description of the A/D output signal in form of a step function (as in the textbooks mentioned above), a new, correct formula for calculating the spectrum of the sampled signal is derived in this paper. It is a revised version of the formula currently used in the literature, that is of the so-called Discrete-Time Fourier Transform (DTFT), and it is a product of this DTFT and a certain correction factor. Finally, some literature items are referred to in which the designers of integrated circuits (containing A/D converters) point out discrepancies that arise in designs when the multiplying factor mentioned above is not taken into account.
calculated and experimetally verified at the laboratory setup.
transmitancji. Odpowiedzi czasowe zostały zweryfikowane eksperymentalnie w laboratorium.
required DC bus reduction. A new controller structure with two proportional-multi resonant controller for the converters with only one of the inductors current as a controlled variable ensures the active damping of the LCL resonance. The power circuit configuration assists the controller to generate a difference in the modulation signal due to non-equal gains in two controllers and helps to achieve the resonance damping without capacitor current sensor. Hence, the corresponding capacitor current sensor can be eliminated. The converter operates for any point of common coupling (PCC) loading conditions and the performance of the controller is immune to the grid impedance variation. A detailed stability study is carried out for the proposed controller. The proposed controller can achieve a very fast dynamic response with an excellent stability margin. The proposed solution is verified through simulation studies and through a scaled-down experimental prototype.
The literature review used an approach based on the bibliometric meta-analysis as visualization tool. Panel data regression modelling was used for the analysis. This study found socioeconomic indicators that can improve the position of a country in DESI. The most significant changes are in the case of research and development expenditure. The results point to the economic and social connections of improving digitalization as strategic managerial implications for policies. The novelty of the study is that it points to economic indicators that impact the improvement of the DESI index and positively affect the future development of the country's digital economy.
napędowych gospodarki cyfrowej. W przeglądzie literatury wykorzystano podejście oparte na metaanalizie bibliometrycznej jako narzędziu wizualizacji. Do analizy wykorzystano modelowanie regresji danych panelowych. Badanie to zidentyfikowało wskaźniki społeczno-ekonomiczne, które mogą poprawić pozycję kraju w DESI. Najbardziej znaczące zmiany dotyczą wydatków na badania i rozwój. Wyniki wskazują na ekonomiczne i społeczne powiązania pomiędzy udoskonaleniem cyfryzacji a strategicznymi implikacjami zarządczymi dla polityki. Nowością tego badania jest wskazanie wskaźników ekonomicznych, które wpływają na poprawę indeksu DESI i pozytywnie oddziałują na przyszły rozwój gospodarki cyfrowej kraju.
dodanej innowacji w wytwarzaniu majątku narodowego oraz rolę rządu w formowaniu stabilnego i przejrzystego otoczenia prawnego sprzyjającego inwestycjom sektora prywatnego w badania i rozwój.
where coopetition– a strategic blend of competition and cooperation– addresses these challenges. Despite its potential to drive innovation and value creation, coopetition networks often struggle to succeed, particularly under the pressures of advancing technology and the need for digital collaboration. To address these issues, this research develops a comprehensive framework that integrates Service-Dominant (S-D) Logic with technology-enabled coopetition networks. Utilizing the Design Science methodology, the study presents a framework that underscores the crucial role of technology in fostering value co-creation within SME networks. This framework is designed to enable sustainable and effective engagement in coopetition, significantly mitigating the risk of network failure by aligning technological innovation with coopetition principles. The proposed framework was evaluated through a targeted survey of managers from SMEs in the Portuguese stone manufacturing sector. The survey results con firmed the practical applicability and potential to promote robust and sustainable coopetition strategies. By integrating theoretical insights with practical applications, this research offers a roadmap for SMEs to effectively manage the complexities of coopetition within the digital supply chain environment.
który częściowo odciąży je na ostatnim etapie przygotowania produktów do sprzedaży.
with a stereophonic module serving as the basic source of modulated signals. Additionally, measurements were conducted on the fundamental parameters of the completed amplifier, such as harmonic distortion level, dynamic range, and output power. The developed platform serves as a foundation for modifications and further advancement in the technology of building switching-mode audio amplifiers.
here. They paved the way to a fully satisfactory and correct result; it is presented in this work. The corrected formula for spectrum calculation is derived using a description of the output signal of an A/D converter by means of the so-called Dirac comb, however not in a direct form, but with taking into account physical reality. In addition, the paper contains a number of interpretative remarks, comments, and explanations - clarifying those matters that have so far been omitted in analyses of the sampling process, despite the fact that they raised various types of doubts.
a non-weighted graph with not all edges between vertices from different d-division of the graph. This article presents new ant algorithms with new desire functions for these problems. These algorithms were tested for their purpose with different changing input parameters, the test results were tabulated and discussed, the best algorithms were indicated.
process can be divided into two stages: green technology R&D and green achievement transformation. The contribution of GTI to economic development and environmental protection depends to a large extent on green innovation efficiency (GIE). Based on the panel data on inputs and outputs of 30 provinces in China from 2007 to 2021, this study applied the super efficiency SBM model considering undesirable outputs to evaluate green technology R&D efficiency (GTRDE) and green achievement transformation efficiency (GATE). Additionally, this study adopted the global and local Moran’s I index for spatial autocorrelation analysis. First, GTRDE showed a trend of “eastern > western > central > northeastern”, while GATE showed a trend of “eastern > central > western > northeastern”. Second, although GATE was higher than GTRDE in most provinces, the differences between provinces were significantly larger for the former than for the latter. Third, global spatial autocorrelation in GIE across provinces was significant only in a few years, while local spatial autocorrelation existed only in a few provinces. Based on the two-stage value chain perspective, the green innovation process is divided into green technology R&D and green achievement transformation. This paper also introduces a super-efficiency SBM model that considers undesirable outputs when calculating GIE. This is in line with the basic laws of GTI and development in reality. Thus, to enhance the efficiency of green innovation, governments and enterprises should raise awareness of GTI, enhance inter-regional exchanges and collaboration, and take a variety of measures to narrow the gap between regions.
conserved quantities of a nonlinear wave equation, existing in three dimensions, and highlight their applications in physical sciences. The robust technique of the Lie group theory of differential equations (DEs) is invoked to achieve analytic solutions to the equation. This technique is used in a systematic way to generate the Lie point symmetries of the equation under study. Consequently, an optimal system of one-dimensional (1-D) Lie subalgebras related to the equation is obtained. Thereafter, we engage the formal Lagrangian of the nonlinear wave equation in conjunction with various gained subalgebras to construct conservation laws of the equation under study using Ibragimov’s theorem for conserved vectors.
speculated that the seismogenic fault is the Kunlun Pass-Jiangcuo Fault based on the spatial distributions of the aftershocks and surface rupture and the strike slip nature of the fault and the mainshock. In addition, a continuous northwest-trending branch fault may exist on the north side of the western section of the Maduo aftershocks. (2) We speculated that the Maduo earthquake was a bilateral rupture based on the media strength of the upper crust and near the surface and the seismic distribution. The findings also provide evidence for the large-scale rupture of the Maduo earthquake. In addition, the high-velocity body to the upper right of the mainshock satisfactorily explains the unobvious rupture above the mainshock. The late weak seismicity indicates that the energy released during the earthquake rupture was sufficient, and it is concluded that the short-term seismic hazard is insignificant. (3) The low S-wave velocity and high wave ratio reflect the existence of crustal fluids in the Maduo area based on the results of previous studies. The Maduo earthquake occurred on the side of the biased high-velocity body in the high-low velocity transition zone, where the stress easily accumulates and is easily released. Therefore, we conclude that the Maduo earthquake accumulated significant stress in the source area. The crustal fluids encountered a hard slope-type high-velocity body and flowed upward into the seismogenic fault, weakening the seismogenic fault. The combined effect of both processes finally triggered the Maduo MS7.4 earthquake.
European cities, Barcelona and Wroclaw. The content analysis of official documents and publicised materials was the basis for describing each city's inclusive strategic policies and marketing initiatives. Considerations based on the literature review and case study led to the conclusions about the strategic role of diversity and inclusion context in city marketing and the use of inclusive marketing in cities’ practices. Findings: By supporting diversity and inclusion, inclusive marketing contributes to developing inclusive cities by creating a climate of equal opportunity and stimulating stakeholder engagement. Marketing cities through diversity and inclusion also strengthens internal and external city image. Practical implications: The article's considerations highlight the essential role of diversity and inclusivity in marketing cities. Demonstrating the value, possibilities, and ways to implement inclusive marketing can contribute to its broader and more strategic use in the practice of cities. Originality/value: Despite growing challenges, inclusive marketing in a territorial context has so far been an understudied area. The article launches the scientific discussion on diversity and inclusion in city marketing, forming the basis for further exploration and developing model solutions.
nicotine. This work used a 96-hour FETAX test to examine how concurrent administration of glucose monohydrate modifies the effects of exposure to nicotine, nicotine sulfate, and/or glucose on ion channels and membrane potential in Xenopus leavis embryos at an early stage of development. In-vitro fertilised embryos were treated with nicotine and glucose alone or in combination for this aim, and the effects of those treatments were then assessed for potential teratogenic effects. At the conclusion of the FETAX technique, the ratios of healthy, abnormal, and dead embryos were calculated, and the length of embryos in each treatment group was assessed. The ratios of abnormal and dead embryos were considerably higher with nicotine treatment alone compared to controls. Compared to the results of the nicotine-alone treatment group, the ratio of aberrant embryos was marginally reduced by concurrent glucose and nicotine therapy. In contrast, the ratio of normal embryos was raised. Additionally, treatments with glucose, nicotine, and Nic+Glu significantly altered the resting membrane potentials of fertilised oocytes (p < 0.001). Our findings indicated that the simultaneous treatment groups that also received glucose had a protective impact on embryos. Such structured, more sophisticated research is required to confirm these findings.
aby systemy mogły pracować niezależnie. Wykonano przykładowe obliczenia wskazujące maksymalny zasięg łącza fronthaul o wybranych szybkościach CPRI/eCPRI. Nakreślono również problematykę związaną z pozapasmowym przenikaniem sygnałów pochodzących z niedoskonałych źródeł optycznej nośnej.
systems could work independently. Exemplary calculations were made indicating the maximum range of the fronthaul link with selected CPRI/eCPRI bitrates. Problems related to out-of-band cross-talk of signals coming from imperfect optical carrier sources are also outlined.
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