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The paper demonstrates the potential of chaining two distinct methodologies in service of topic modelling. The first, as of recent years, is more-or-less standard natural language processing (NLP) with word2vec; the second is graph-theoretical or combinatorial algorithm. Together, we show how they may be used to help classify documents into distinct, but perhaps not disjointed, classes. The procedure is demonstrated on a collection of Twitter feeds, or tweets. Heuristics is the basis for this procedure; it is not presumed to perfectly work in every situation, or for every input, and, in fact, the authors believe that the procedure will yield better results in a more homogeneous corpora written in some standardized fashion, as written in, e.g., legal or medical documents.

This paper presents a stacked-topology resonant switched-capacitor (ResSC) dc-dc converter to achieve a high voltage conversion ratio. The topology can be generalized to any N-to-1 dc-dc conversion application with only a single inductor. Multiphase interleaving can be further employed to improve the ripple cancellation and reduce requirement for bypass capacitors. To enable a wide output range while maintaining high efficiency, a phase shift operation is adopted. The regulation is maintained with frequency modulation. The controller is designed with the aid of current phase compensation in addition to voltage mode control. A prototype of a nominal 4-to-1 two phase interleaved resonant switched capacitor converter has been built and tested. The control and regulation of the output voltage are verified through the experiment. Burst mode is further introduced to improve efficiency at the light load condition.

This paper presents an approach for nominally lossless regulation of the output voltage, and for design of tight closed-loop voltage control of a resonant switched-capacitor (ResSC) dc-dc converter. A switching pattern for the ResSC dc-dc converter that enables wide range lossless voltage regulation and zero voltage switching (ZVS) is developed. An appropriate small signal model is derived based on the generalized averaging method. In view of the dynamics of the developed small signal transfer functions, a compensation method based on a minor phase loop is introduced to stabilize the system. The steady state and transient responses of the system are evaluated based on the developed model. The performance of the proposed controller is verified by a switch-based simulation in a design example for on-chip power delivery application.