This paper presents the design, implementation and testing of a microprocessor-based high-speed relay that correctly detects transformer winding faults. Instead of relying on the presence of harmonics to identify magn...
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This paper presents the design, implementation and testing of a microprocessor-based high-speed relay that correctly detects transformer winding faults. Instead of relying on the presence of harmonics to identify magnetizing inrush, it uses a non-linear model of the transformer to determine the state of its health. One version of the relay is suitable for protecting single-phase transformers, whereas another version is for protecting three-phase transformers. A three-phase delta-wye 15 kVA transformer was used to test the relay for a variety of operating conditions. The results show that the relay performs well.
Data gathering and information processing have evolved to where it is almost unfathomable how much exists in digital form today. The generation thereof also no longer involves an explicit instruction from human to mac...
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Data gathering and information processing have evolved to where it is almost unfathomable how much exists in digital form today. The generation thereof also no longer involves an explicit instruction from human to machine but can happen in real-time without human intervention. Artificial intelligence, machine learning, and cognitive computing are being utilized to mine data from a variety of sources. One such (profitable) source is human beings. digital algorithms are designed to harness the power of technology to gather information. There has always been a sense of secrecy regarding some information (classified, top secret, confidential, etc.) but the Fourth Industrial Revolution has created the means to gather extremely large amounts of data, unknown to its sources. Anthropological value systems should become a fundamental foundation of digital algorithms. Such an approach could prevent software from exploiting its sources, especially minorities. Value systems together with ethics are guided by people's culture. In ethically aligned algorithm design, value systems and digital technologies intersect and govern how algorithms are developed, the way data is engaged, and further the discipline of digital humanities.
With the wide application of digital media technology and augmented reality, in order to enhance the design experience of mobile visual media design. This paper uses domain processing, point processing, big picture pr...
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With the wide application of digital media technology and augmented reality, in order to enhance the design experience of mobile visual media design. This paper uses domain processing, point processing, big picture processing and model processing in numerical algorithms, construction of visual media images based on additive and multiplicative models, integrating the SOR model with the EDT model, build PLS model. Depending on the interactivity, patios-temporal fixity and degree of immersion of the virtual object, analyze the results of PLS experience conceptual model construction by combining system characteristics and cognitive elements of mobile visual media design. To explore the mechanisms by which digital media technologies and augmented reality technologies influence the design factors of mobile visual media, and evaluate the measurement model and structural model. The results of the evaluation found that accuracy 0.325, flexibility 0.472 and completeness 0.328 positively and significantly influenced information quality (R=0.697), system quality (R=0.52) and service quality (R=0.741). The system quality, information quality and service quality of the mobile visual media design products are guaranteed.
Scholars have theorized the use of chance processes in modern art in general, and in computer-based art in particular, as the expression of an aesthetics of nonintention and authorial abnegation. Although writers of c...
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Scholars have theorized the use of chance processes in modern art in general, and in computer-based art in particular, as the expression of an aesthetics of nonintention and authorial abnegation. Although writers of computer-generated poetry in the United States make extensive use of computer-based randomization, their creative adventures with computational indeterminacy do not lead them to endorse an aesthetics of nonintention or authorial abnegation. Rather, they cultivate different forms of authorial intentionality and pursue different and often-conflicting goals. These tensions result from computational indeterminacy's affordances in relation to the different and often-conflicting cultural currents that inform contemporary US liberal subjectivity. These currents include calls to advance social justice and inclusivity;an emphasis on self-determination;a willingness to approach technology as an inscrutable, autonomous, and self-determining form of creative agency;and the celebration of rarefied aesthetic abstraction and experimentation as a form of expressive freedom.
Differential protection is more appropriate for multi-terminal lines than distance protection, due to its selectivity. However, the sampling process at all terminals should be synchronized. The new methods presented d...
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ISBN:
(纸本)0780371739
Differential protection is more appropriate for multi-terminal lines than distance protection, due to its selectivity. However, the sampling process at all terminals should be synchronized. The new methods presented don't need the sampled values for comparison and therefore no synchronization. Firstly, the positive-sequence component of currents and voltages is calculated from the sampled values. Then, using line parameters, currents and voltages as well the admittances or apparent powers at the tap points are calculated for each line section. The sum of the admittances, and also the sum of apparent powers are equal to zero for the sound line. Phase shifts between currents at all terminals In the prefault stage, caused by the not synchronized sampling can also be calculated. An appropriate sum of currents at the tap point is also equal to zero under sound line conditions. The proposed methods are especially suitable for detection of faults with considerable impedances.
Automatic synchronizers are widely employed to connect synchronous generators to power system. The core task of a synchronizer is to estimate the voltage magnitude, frequency and phase angle difference between the gen...
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ISBN:
(纸本)9781424401109
Automatic synchronizers are widely employed to connect synchronous generators to power system. The core task of a synchronizer is to estimate the voltage magnitude, frequency and phase angle difference between the generator terminal and the system bus accurately and rapidly. This paper introduces a novel automatic synchronizer, which consists of two independent CPU modules running under completely different principles, the hardware based one and the software based one respectively. The design of the hardware based CPU module is described, and the new parameter estimating algorithm in the software based CPU module is proposed and detailed. The new algorithm can estimate the parameters precisely with a fixed sampling frequency, even when signal frequency is time varying. The cooperation and coordination between the two CPU modules are discussed. Due to the different working principles and independent hardware circuits, the probability of false synchronization decision that made by both CPU modules at a same time is minimized, therefore, the reliability of the synchronization is improved. The results of both laboratory tests and engineering applications prove the good performance of the developed device.
A digital computer algorithm is developed for on-line time differentiation of sampled analog voltage signals. The derivative is obtained by employing a least mean squares technique. The recursive algorithm results in ...
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The platformization seems to be a demiurgic force, increasingly (re)shaping this millennium and its socio-economic, technological and physical structures, institutions, and human lives. Innovation ecosystems are exper...
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The platformization seems to be a demiurgic force, increasingly (re)shaping this millennium and its socio-economic, technological and physical structures, institutions, and human lives. Innovation ecosystems are experiencing this platformization, leading to the rise of platform-based innovation ecosystems. However, the industrial and managerial literature still lacks a shared definition, a consistent theoretical and strategic frame-work to explain how platform-based innovation ecosystems emerge and replicate from market to market. This conceptual work attempts to fill those gaps by integrating the extant literature on innovation ecosystems in two ways. First, moving from the literature on innovation ecosystems and industry platforms, using systems thinking framing, it explains the platformization of innovation ecosystems through the double lens structure-system. Second, it identifies the holographic strategy as one of the typical patterns featuring platform-based innovation ecosystem envelopment beyond extant market boundaries. These conceptualizations have insightful theoretical, managerial, and policy implications. In particular, the work discusses the ecosystem as a valid unit of analysis for understanding such an unprecedented shaped-by-platform landscape. Then, it describes the growth strategies of the platform-based innovation ecosystem supporting the platform sponsor in mastering multipoint competition. Eventually, the study pinpoints crucial issues for policymakers in regulating the impact that plat-formization is having on society.
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