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With a radical energy transition fostered by the increased deployment of renewable non-programmable energy sources over conventional ones, the forecasting of distributed energy production and consumption is becoming a cornerstone to ensure grid security and efficient operational planning. Due to the distributed and fragmented design of such systems, real-time observability of Distributed Generation operations beyond the Transmission System Operator domain is not always granted. In this context, we propose a Machine Learning pipeline for forecasting distributed energy production and consumption in an electrical grid at the HV distribution substation level, where data from distributed generation is partially observable. The proposed methodology is validated on real data for a large Italian region. Results show that the proposed model is able to predict up to 7 days ahead the amount of load and distributed generation (and the net power flux by difference) at each HV distribution substation with a 24%-44% mean gain in out-of-sample accuracy against a non-naive baseline model, paving the way to advanced and more efficient power system management.

This article presents the design of a new closed loop technique that reduces the common mode conducted emission. It can be applied to any kind of switching circuit in which couples of outputs are modulated by a bipolar PWM signal. It is based on the compensation of the delay between complementary output switching edges, using a simple sensing circuit and a low computational effort software algorithm, which is implemented in a microcontroller driving the switching circuit. One of the main advantages of the proposed solution is the reduction of the disturbance energy, without affecting the system efficiency. The technique is practical to implement, and the measurements performed on a power inverter prototype confirm the theoretical analysis outcomes about the reduction of the conducted emission in the lower-to-medium frequency range.

The purpose of this short paper is to build theory and to stimulate further research on knowledge sabotage, the most extreme counterproductive behavior that hinders knowledge sharing. Following a comprehensive analysis of the literature, we identified nine original conceptual propositions which shape an innovative framework of individual-, group- and organizational-level factors. The proposed framework offers the key factors that are relevant for a better conceptualization of knowledge sabotage, thus representing a fertile ground for new empirical studies. Since the recent formalization of the "sabotage" of knowledge, this paper is the first that presents such influencing factors thus opening the way for a better understanding of the dynamics that inhibit knowledge sharing.

This paper analyzes the influence of the load parasitics on the conducted electromagnetic emissions, especially on their common mode component. The analyses have been performed on a BLDC motor driver, switched with bipolar PWM. According to the final installation of both the electronic module and the load, the prescribed test setup for the electromagnetic interference (EMI) measurements can vary. This modifies the parasitic element values and it can even worsen the emission level, when the load chassis is connected to the reference plane. In this paper, the effect of the load parasitic elements on the conducted emission is analyzed in details, and an equivalent model is derived and verified by simulation. Moreover, such simulations proved that the delay compensation technique can be used to counteract the EMI increase due to the load parasitics.

We introduce a new family of error correction codes based on sparse superposition called Quasi- Orthogonal} Sparse Superposition Codes (QO-SSC). The core of QO-SSC is a special structure of the SSC projection matrix which is obtained by concatenation of orthogonal submatrices. Concrete examples of QO-SCC constructions based on Zadoff- Chu sequences and Kerdock bent sequences are provided. A low-complexity iterative successive interference cancellation algorithm is proposed for QO-SSC decoding. Performance evaluations show that QO-SSC is an efficient solution for short- packet transmission at low signal-to-noise ratios, as it achieves lower block error rate than conventional coded modulation schemes, e.g., QPSK- modulated polar codes. As a further advantage, QO-SSC features a low PAPR when transmitted using OFDM waveforms.

We propose a novel Simultaneous Wireless Information and Power Transmission (SWIPT) scheme to enable a compatible multiplexing of energy and information based on the frequency that can be used with the state-of-art transceivers. In the proposed scheme, the transmitter superimposes a Direct-Current (DC) signal on Orthogonal Frequency-Division Multiplexing (OFDM) Radio Frequency (RF) signal to generate OFDM-DC signal for SWIPT where the OFDM part is used for information transmission and the DC signal is used for energy transfer. The power level of the DC signal is configured by a controller at the transmitter side. The corresponding receiver is constructed with direct-conversion-receiver front-end such that the DC signal is extracted using a low-pass filter whose bandwidth is configured based on the subcarrier spacing of the OFDM waveform and then fed to a voltage-to-current converter to generate current to charge a battery for energy storage. The OFDM signal without DC power signal is then fed to Analog-to-Digital (A/D) converter for information decoding. The numerical and simulation evaluations provide encouraging evidence in the favor of the proposed OFDM-DC scheme.

Electromagnetic emissions (EMEs) of electric and electronic units should comply with national and international standards. Software approaches to reduce the conducted EME are preferable, since they do not require additional on-board hardware. Many techniques have been developed with different levels of efficiency. This paper aims to analyze a new software approach to mitigate the conducted emissions of three-phase power inverters, focusing on those used to drive brushless DC motors. This has been done reducing the conducted electromagnetic interferences common mode (CM) component through software compensation of parasitic delays. The technique is verified both analytically and experimentally, and its performances have been compared to the spread spectrum modulation (SSM) ones. The proposed approach shows better performances with respect to SSM below 24 MHz. The results confirm the effectiveness of the delay compensation technique in terms of CM conducted emissions reduction. Moreover, the proposed approach has no drawbacks on safety and it does not present reductions in the inverter efficiency.

The techniques used to reduce the electromagnetic interferences (EMI) generated by power inverters, in order to comply with the standards, can be classified as hardware and software. The latter are usually preferred because cheaper and flexible. Often the inverter output waveforms, which are modulated by bipolar PWM, are not perfectly aligned, due to the delay introduced by the circuit components. This misalignment generates common mode (CM) conducted emissions. Among the software approaches, one consists in aligning these output waveforms. The present paper proposes a new EMI on-board sensing technique to control the output waveform alignment. Mixed-signal simulations show that the proposed technique is able to reduce the CM emission spectrum over a wide frequency range. Moreover, this approach does not affect either the power loss or the system safety.

This paper presents a low power DC-DC buck-boost topology functioning battery-less on the basis of a novel technique using a combination of both: singular optimal control plus an analog circuit control law. The very low power consumptions along with the optimal energy harvested, makes possible to perform FFT calculations on-line and on-chip for vibration analysis applied to wind-turbines maintenance operation using an ST microcontroller and transmitting up to 500 m. The complete functioning circuit is shown along with real measurements.

In vivo cardiac microstructure acquired using cardiac diffusion tensor imaging (cDTI) is a critical component of patient-specific models of cardiac electrophysiology and mechanics. In order to limit bulk motion artifacts and acquisition time, cDTI microstructural data is acquired at a single cardiac phase necessitating registration to the reference configuration on which the patient-specific computational models are based. Herein, we propose a method to register subject-specific microstructural data to an arbitrary cardiac phase using measured cardiac displacements. We validate our approach using a subject-specific computational phantom based on data from human subjects. Compared to a geometry-based non-rigid registration method, the displacement-based registration leads to improved accuracy (less than 1° versus 10° average median error in cardiomyocyte angular differences) and tighter confidence interval (3° versus 65° average upper limit of the 95% confidence interval).

During the last years, the use of Domain Generation Algorithms (DGAs) has increased with the aim of improving the resiliency of communication between bots and Command and Control (C&C) infrastructure. In this paper, we report on an effective DGA-detection algorithm based on a single network monitoring. The first step of the proposed method is the detection of a bot looking for the C&C and thus querying many automatically generated domains. The second phase consists on the analysis of the resolved DNS requests in the same time interval. The linguistic and semantic features of the collected unresolved and resolved domains are then extracted in order to cluster them and identify the specific bot. Finally, clusters are analyzed in order to reduce false positives. The proposed solution has been evaluated over (1) an ad-hoc network where several known DGAs were injected and (2) the LAN of a company. In the first experiment, we deployed different families of malware employing several DGAs: all the malicious variants were detected by the proposed algorithm. In the real case scenario, the algorithm discovered an infected host in a 15-day-long experimental session, while producing a low false-positive rate during the same period.

The growing importance of the online channel and the increased deployment of new technologies such as smart mobile devices and social networks create new opportunities and challenges for traditional retailers. The retailing industry is moving to a new phase, in which the distinctions between traditional and online channels disappear, namely omni-channel (OC) retailing. The new challenge is to understand how multiple channels can be synergistically managed to provide a seamless customer experience. In OC retailing, logistics represents a key success factor due to its impact on both customer service and total costs. Retailers need to define the distribution configuration for serving the online demand, making decisions on the integration level between online and traditional channels. Companies can set an ad hoc network for the online channel, or use the same network for both online and traditional channels at warehouse and/or transport levels. In this paper, we developed an assessment model of the operational costs for three distribution configurations in OC retailing. The model was also applied to a real Italian case operating in the consumer electronics industry. Results highlighted that the search for synergies between online and traditional flows in both warehouse and transport activities is important for the economic sustainability of OC systems.

Superposed transmission on the broadcast channel delivers multiple private messages simultaneously to the intended users. Superposed transmission is employed in non-orthogonal multiple access to increase the aggregate throughput and connectivity of wireless cellular systems. Rate-adaptive constellation Expansion Multiple Access (REMA, a.k.a. RA-CEMA) is a non-orthogonal multiple access scheme which exhibits performance similar to the conventional superposed transmission schemes for transmission on the degraded broadcast channel, while requiring less complex signal processing and scheduling algorithms. This paper solves the problem of user scheduling and rate~allocation for REMA. We pose the problem as a weighted sum-rate optimization and develop provably optimal algorithms for user selection and rate allocation with REMA broadcast-channel transmission. System-level evaluations show that our schemes outperform an LTE-A compliant orthogonal multiple access system and exhibit similar or better performance compared to other known non-orthogonal multiple access schemes.

The IC stripline method is one of those suggested in IEC-62132 to evaluate the susceptibility of ICs to radiated electromagnetic interference. In practice, it allows the multiple injection of the interference through the capacitive and inductive coupling of the IC package with the guiding structure (the stripline) in which the device under test is inserted. The pros and cons of this method are discussed and a variant of it is proposed with the aim to address the main problems that arise when evaluating the susceptibility of ICs encapsulated in small packages.

This paper analyzes how the switching noise generated in the power section of common three leg inverters used to drive BLDC motor gives rise to common mode conducted emissions. Besides the identification of the primary sources of switching noise and the parasitic elements that usually play a key role in the propagation of such disturbances, a new method based on a tight control of the power MOS commutation time is proposed. Its effectiveness is shown through simulation and measurement results.

A new non-orthogonal multiple access scheme performing simultaneous transmission to multiple users characterized by different signal-to-noise ratios is proposed. Different users are multiplexed by storing their codewords into a multiplexing matrix according to properly designed patterns and then mapping the columns of the matrix onto the symbols of a higher-order constellation. At the receiver, an interference cancellation algorithm is employed in order to achieve a higher spectral efficiency than orthogonal user multiplexing. Rate-Adaptive Constellation Expansion Multiple Access (RA-CEMA) is an alternative to conventional superposition coding as a solution for transmission on the degraded broadcast channel. It combines the benefits of an increased spectral efficiency with the advantages of reusing the coding and modulation schemes already used in contemporary communication systems, thereby facilitating its adoption in standards.

We propose a new overloaded multiple access scheme based on Turbo Trellis Coded Modulations (TTCM) which, thanks to the high gain provided by turbo coded schemes, exhibits improved performance with respect to other solutions based on Trellis Coded Modulation (TCM). Turbo Trellis Coded Multiple Access (TTCMA) performs simultaneous transmission of multiple turbo-encoded and modulated data streams intended for users experiencing similar Signal-to-Noise Ratios (SNR). Stream-specific permutations are employed in turbo code interleavers to enable stream identification and separation at the receiver. An efficient solution for the generation of sets of such permutations is also provided. TTCMA overcomes known limitations of previous TCM-based schemes, achieving a high aggregate spectral efficiency even at low SNR by exploiting the large coding gains provided by parallel concatenated schemes when the size of the transmitted information words is large.

We propose an enhanced version of trellis coded multiple access (TCMA), an overloaded multiple access (MA) scheme that outperforms the original TCMA in terms of achieved spectral efficiency. Enhanced TCMA performs simultaneous transmission of multiple data streams intended for users experiencing similar signal-to-noise ratios and can be employed both in the Up-Link (UL) and in the Down-Link (DL) of wireless systems, thus overcoming one of the main limitations of TCMA. Thanks to a new receiver algorithm, ETCMA is capable of delivering a significantly higher spectral efficiency (SE). We show that ETCMA approaches the capacity of the Additive White Gaussian Noise (AWGN) channel for a wide range of SNR values.