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Abstract In the process of penicillin fermentation, there is a strong nonlinear relationship between the input eigenvector and multiple output vectors, which makes the prediction accuracy of the existing model difficult to meet the requirements of chemical production. Therefore, a local selective ensemble learning multi-objective soft sensing modeling strategy is proposed in this study. Firstly, a localization method based on transfer entropy and k-means is proposed to reconstruct the sample set. Then, based on the reconstructed local samples, the local soft sensing model is established by the multi-objective support vector regression method, and the selective ensemble of sub-models and the adaptive calculation of prediction weights are realized. At the same time, to reduce the adverse effects caused by improper selection of model parameters, the sparrow search algorithm is used to realize the tuning of the mentioned model parameters. Finally, the proposed modeling strategy is simulated. The results show that, compared with other methods, the proposed local selective ensemble learning multi-objective soft sensing modeling strategy has better prediction performance.

Summary: Traditional multiple‐output AC‐DC power supply with power factor correction (PFC) function usually employs a two‐stage cascaded topology that is composed of prestage PFC converter and N independent poststage DC‐DC converters to achieve PFC and voltage or current regulation of N outputs. Hence, the conventional two‐stage cascaded multiple‐output AC‐DC power supply needs N + 1 magnetic components as power inductors or transformers and N + 1 controllers, which increases the cost and size of the multioutput converters. The conventional multiple‐string AC‐DC LED driving circuits usually employ a two‐stage topology to realize PFC and independent current regulation of each LED string. To address the issue of complexity, high cost, and large size of the two‐stage multistring LED driving circuit, a single‐stage triple‐output Cuk PFC converter is proposed by cascading boost converter and single‐inductor triple‐output buck converter with sharing main power switch in this paper. The topology operation principle, control strategy, design consideration, and operation characteristics of the proposed circuit are investigated in detail. With the switch sharing and inductor multiplexing technologies at the same time, the proposed converter utilizes only single‐stage converter to achieve PFC function, independent regulation of triple‐channel output current, and flicker‐free with low twice line frequency LED current ripple. The proposed converter is verified by a 50‐W experimental prototype of LED driver for triple string LEDs. The proposed converter only uses two power inductors and a set of controller to achieve greater than 0.945 PF, up to 90.5% efficiency, low LED current ripple, and independent current regulation for triple LED strings with different forward voltage, which may significantly reduce the cost and size of the traditional AC‐DC multistring LED driving circuit. [ABSTRACT FROM AUTHOR]

Induction heating appliance operation is constrained by the nonlinear pot material behavior under the generated magnetic field. The equivalent load seen by the inverter varies with the intensity of the field, meaning that this variation is dependent on the mains voltage. In flexible-surface induction cooktops, this fact is combined with a high coil number and different pots to be powered simultaneously, increasing the complexity to control the transmitted power while maintaining proper mains current consumption. In this article, two noncomplementary asymmetrical modulations with in-cycle parameter variation are proposed for improved power factor correction while avoiding the need for switching frequency variation and intermodulation noise in multiload systems. The proposed strategies are analyzed and experimentally tested using a 3.6 kW multi-inverter prototype featuring five induction coils. [ABSTRACT FROM AUTHOR]

A nonisolated integrated multiple output synchronous buck converter is proposed in this article to cater the auxiliary power supply requirements of e-mobility. The converter provides independently controlled multiple outputs with reduced switch count as compared to conventional separate buck converters as well as conventional synchronous buck converter. The operating principle and working of the proposed converter are discussed in detail for better understanding. As the dynamic behavior of the converter is similar to the conventional buck converter, a simple controller is designed and implemented in this work. The converter is simulated in MATLAB-Simulink. A laboratory prototype of single input–quadruple output (SIQO) converter is developed and operated under closed loop condition to validate and demonstrate its advantages. The prototype is developed by designing two inductors on a single core for increased compactness and reduced cost of the converter. Each output of the converter can be independently controlled by varying the duty ratio of the related switch, thereby eliminating the effective cross regulation problem. The efficiency of the proposed SIQO converter is 93.6%, with four output ports, which is higher than its category of converters reported earlier. A significant improvement in the calculated efficiency is observed with the replacement of conventional switches and diodes of the converter by SiC switches (96.1%). [ABSTRACT FROM AUTHOR]

In terms of predicting the flow parameters of a river system, such as discharge and flow depth, the continuity equation plays a vital role. In this research, static- and routing-type dynamic artificial neural networks (ANNs) were incorporated in the multiple sections of a river flow on the basis of a storage parameter. Storage characteristics were presented implicitly and explicitly for various sections in a river system satisfying the continuity norm and mass balance flow. Furthermore, the multiple-input multiple-output (MIMO) model form having two base architectures, namely, MIMO-1 and MIMO-2, was accounted for learning fractional storage and actual storage variations and characteristics in a given model form. The model architecture was also obtained by using a trial-and-error approach, while the network architecture was acquired by employing gamma memory along with use of the multi-layer perceptron model form. Moreover, this paper discusses the comparisons and differences between both models. The model performances were validated using various statistical criteria, such as the root-mean-square error (whose value is less than 10% from the observed mean), the coefficient of efficiency (whose value is more than 0.90), and various other statistical parameters. This paper suggests applicability of these models in real-time scenarios while following the continuity norm. HIGHLIGHTS Applicability of Continuity equation while forecasting using ANN.; Use of storage variable in river flow prediction.; Routing type dynamic ANN models implication.; Use of MIMO (multiple input and multiple output) and MISO (multiple input and single output) model forms for forecasting approach.; Model is applicable and useful in real time flood scenarios.;

Multi-output inverters have become a key enabling technology to increase surface flexibility in domestic induction heating appliances. The most commonly used power converter topologies are based on electromechanical relays in order to multiplex the connected loads and obtain a proper heat distribution. This solution, which is used in combination with other modulations such as square waveform, relies on the thermal inertia of the pot as it needs long power-averaging periods to reduce the reiteration of the switching noise. However, it presents a significant limitation in terms of acoustic noise, reliability, and thermal performance. To overcome these limitations, complete solid-state inverters that can be operated at higher frequencies are proposed. This change in the design paradigm of the pulse density modulation strategies leads to improved thermal control in the pot and better user experience, but at the same time increases challenges due to design constraints imposed by electromagnetic compatibility regulations. This article analyzes the possibilities of a new mains-synchronized pulse density modulation applied to a flexible induction cooktop that uses a multiple-output ZVS resonant inverter topology. The feasibility of the control strategies has been tested by means of a prototype featuring 12 2-kW induction heating loads. [ABSTRACT FROM AUTHOR]

Based on the analysis of the structural characteristics of the internal meshing gear pump with multi-output, the main leakage ways in the gear pump are summarized. By establishing the mathematical formula of leakage, the general formula of the total leakage of the gear pump under three working modes is obtained, and the volume efficiency of the pump is calculated. It is concluded that the volume efficiency of the internal meshing gear pump with multi output is the highest when the internal pump is used alone, and the volume efficiency of the external pump alone is the lowest. The structure of internal gear pump with multi output is improved to reduce the leakage and is verified via experiments. The experimental results show that the volumetric efficiency of the pump is consistent with the analysis results, that is, the volume efficiency decreases with the increasing of load pressure of pump.

An MC3 LLC resonant light-emitting diode (LED) driver is a multi-channel constant current (MC3) output solution based on LLC resonance. Through an effective combination of multiple transformers and a DC block capacitor, this driver allows constant current outputs in multiple channels when the LED channels are unbalanced. This study considers a fuzzy self-tuning proportional integral derivative (PID) control strategy that allows for the self-tuning of PID parameters according to fuzzy inference rules designed using the relationship between the current gain and the switching frequency. Thus, when LED channels are unbalanced, the system allows a constant current output for each of the channels and controls the input voltage disturbances well. Simulation and experimental verifications are carried out, and a 20 W 4-channel constant current power supply design based on LLC resonance is obtained for the LED driver. This realizes soft-switching of the switching device, which reduces system loss and improves system efficiency. Moreover, the adjustment time of the proposed method is half that of fixed-parameter control methods, and the overshoot of the proposed method is smaller than that of fixed-parameter control methods. When compared with PID controllers with fixed parameters, the proposed method is more robust. When a system is disturbed, it recovers faster and has a smaller range of current fluctuation with the proposed method. [ABSTRACT FROM AUTHOR]

Soft sensors are the most commonly used tools to predict hard-to-measure variables in industrial processes. However, the presence of a large number of hard-to-measure variables always renders a generic single-output soft-sensor inadequate. This brief proposed two multiple-output soft sensors, the former based on a novel serial stacking relevant vector machine (RVM) models, called RVMS, by transforming multiple-output into single-output problems inspired by stacking generation and the latter based on ensemble multivariable RVM (EMRVM) models that are improved by ensemble learning. To further strengthen the predicted ability, least absolute shrinkage and selection operator and canonical correlation analysis are used to remove irrelevant and redundant information from raw features under the supervision of multivariate targets for RVMS and EMRVM, respectively. The proposed methodologies were first accessed by a well-established wastewater plant (WWTP) validation platform, Benchmark Simulation Model No.1 then evaluated by a real WWTP with data being collected from the field. The results demonstrated that the proposed strategies were able to significantly improve the prediction performance. [ABSTRACT FROM AUTHOR]

Microsystems that sense, process, and communicate data can save money, energy, and lives. Such varied functionality, however, demands power that can easily deplete a small battery. Integrating so many analog and digital functions can also imperil performance with noise and distortion. To survive all this with an exhaustible battery, blocks require several efficient power supplies that both buck and boost the battery voltage. Luckily, switched inductors are flexible and efficient, but also bulky. So what these microsensors need are single-inductor multiple-output supplies that buck and boost. But to reconfigure the inductor for such diverse operation requires many power-consuming switches. Plus, cycling between outputs requires time and delays response time. The single-inductor supply proposed bucks and boosts and cycles between outputs frequently with two input switches, one inductor, and one switch and one capacitor per output. Other buck–boost supplies either bypass the inductor or require one to two more switches and up to one more inductor and one more capacitor. The prototype presented here bucks two outputs and boosts one output with five switches by energizing the inductor to buck outputs first. By collecting sufficient energy this way, the inductor can feed boost outputs directly. A sixth switch engages only when boost power is greater than a threshold that the input voltage and buck power levels establish. This way, the 0.6-μm complementary metal oxide semiconductor system bucks and boosts 2.7–4.0 V to 1.2, 1.8, and 4.0 V to deliver 80%−87% of the 379–412 mW drawn. The system cycles every 1–3 μs and responds within 5–10 μs. [ABSTRACT FROM AUTHOR]

This paper proposes a novel integrated synchronous buck converter for the auxiliary power supply system of electric vehicles, which achieves multiple independently regulated outputs with reduced switching components in comparison with the conventional separate buck converters. In order to obtain a better understanding of the proposed converter, operational principle and performance characteristics of a simplified dual-output buck converter are introduced in detail, as an example. The analysis shows that zero-voltage-switching operation and lower conduction losses could be attained. In addition, its dynamic behavior is similar to the conventional buck converter and thus the controller design is simple. Finally, experimental results based on a prototype circuit in which two inductors are integrated into one magnetic core to achieve further reduced cost are demonstrated to verify the advantages. [ABSTRACT FROM PUBLISHER]

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In cyber-physical systems such as intelligent lighting, the system responds autonomously to observed changes in the environment. In such systems, more than one output may be acceptable for a given input scenario. This type of relationship between the input and output makes it difficult to analyze machine learning algorithms using commonly used performance metrics such as classification accuracy (CA). CA only measures whether a predicted output is right or not, whereas it is more important to determine whether the predicted output is relevant for the given context or not. In this direction, we introduce a new metric, the relevance score (RS) that is effective for the class of applications where user perception leads to non-deterministic input-output relationships. RS determines the extent by which a predicted output is relevant to the user's context and behaviors, taking into account the variability and bias that come with human perception factors. We assess the performance of a number of machine learning algorithms, using different datasets, including data from an intelligent lighting pilot. We find that using RS instead of CA is appropriate to analyze the performance of conventional machine learning algorithms, particularly for the class of non-deterministic multiple-output problems. Our method may be applied to other scenarios in which cyber-physical systems involve humans in the control loop. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Aming at simplifying the complex and costly RGB LED lighting system which requires multiple LED drivers, an individually con­trollable multi-outputs LED driver based on secondary side post regulation (SSPR) was proposed. The proposed LED driver was based on multi-outputs flyback converter with additional secondary side MOSFETs. The time-sharing multiplexing control was applied to make each output current individually controllable. The system configuration, operation principle and system development were analyzed in detail. A prototype was designed to verify the theoretical analysis. The results indicate that the proposed LED driver can output multiple individually controllable currents and get no influence from the load voltage and the transformer turns ratio. [ABSTRACT FROM AUTHOR]

Aiming at the problem of multiple output of the soft PLC，the conversion algorithm of PLC function block diagram (FBD) to instruction list (IL) based on Nary Trees was proposed and implemented. In this algorithm, firstly，the FBD program is mapped to the Nary Trees. On this basis，through decomposition and reorganization of the Nary Trees，the complex tree structure generation was decomposed into a collection of ordered subtree structure. And then the decomposed tree structures are sequentially visited in the post-order traversal way. Depending on the diferent nodes types which are translated into the corressponding IL，the PLC FBD，finaiy，was achieved to be converted to the IL. An example was given to illustrate the ideas and implementation steps of the algorithm. Experimental verification of soft PLC host computer system ，based on the IEC61131-3 international standard，was carried out. The experimental result shows that the algorithm is a general conversion algorithmfor conversion of complex FBD with multiple outputs into IL. And in the process of the conversion，the algorithm can preferably simplify the procedures，save more memory space and improve the efficiency of PLC FBD compilation conversion. [ABSTRACT FROM AUTHOR]

Support vector regression has been considered as one of the most important regression or function approximation methodologies in a variety of fields. In this paper, two new general dimensional multiple output support vector regressions (MSVRs) named SOCPL1 and SOCPL2 are proposed. The proposed methods are formulated in the dual space and their relationship with the previous works is clearly investigated. Further, the proposed MSVRs are extended into the multiple kernel learning and their training is implemented by the off-the-shelf convex optimization tools. The proposed MSVRs are applied to benchmark problems and their performances are compared with those of the previous methods in the experimental section. [ABSTRACT FROM PUBLISHER]

In this letter, a quasi two-stage architecture is proposed for wide input voltage range (voltage ranges ≈ 1:2) and high step-down multiple output conversion. A dc-DCX, which operates as a dc-dc converter with regulated output when the input voltage is low and as a dc-dc transformer with unregulated output when the input voltage is high, is adopted in the first stage to provide optimized intermediate dc-bus voltages for the second-stage point-of-load converters. The input and output of the dc-DCX are in series and connected to the total input voltage. Hence, part of the input power is directly transferred to the intermediate bus without conversion. The devices' voltage stresses and the transformer turns ratio of the dc-DCX are reduced by using the proposed quasi two-stage architecture. Thus, the conversion efficiency is improved significantly. Furthermore, a dual-output LLC resonant converter with hybrid center-tapped and full-bridge rectifier is proposed for the dc-DCX to achieve high efficiency and high power density. A 100-W prototype with three outputs is built and tested to verify the analysis. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with the discrete multitone multiple input, multiple output interference channel (DMT MIMO IC) in DSL networks. The scenario consists of a number of users, each with a given number of transceivers, that share the same channel in multiple tones. Our goal is to maximize the weighted rate sum of the users subject to power constraints. A recent paper has treated this problem with per-user power constraints. In this paper we focus on per-transceiver power constraints. We propose two different algorithms. First, we straightforwardly adapt the previously proposed DMT-WMMSE algorithm. Second, we adapt the WMMSE-GDSB, in which we separate the problem in signal and spectrum coordination parts. For the spectrum coordination part, we show that the problem can be solved more efficiently with a change of variables: we use a coordinate system consisting of a radius and a direction vector with ℓ1 norm equal to 1. This can be interpreted as spherical coordinates in taxicab geometry. It is observed that for the radial dimension the problem can be made concave after approximations and it is thus easy to solve. The remaining dimensions are solved with a sequence of line searches. Simulation results show that the WMMSE-GDSB converges faster. [Copyright &y& Elsevier]

An ac-dc rectifying system for vibration energy harvesting is proposed to generate outputs of four different voltage levels with a single power source. The proposed dual-output rectifier uses only four diodes, similar to a conventional single-output full-bridge rectifier. A switched-capacitor down-converter provides two output voltages from a single input from the voltage doubler by using the proposed load balancer with a low design complexity. The proposed system is implemented in a 0.35-μm CMOS process, and it occupies an area of 0.143 mm 2. [ABSTRACT FROM AUTHOR]

A complicating aspect in the control design of resonant inductive power transfer systems is the absence of a direct communication link between primary and (multiple) secondary system sides. This paper introduces a new adaptive sliding-mode control surface, which continuously adapts the inductive system's input power to the required, but unknown, variable load power. As a result, an indirect communication link is redundant. Furthermore, due to matching input and output power, optimum relative system efficiency is automatically guaranteed in the entire system's output power range. The controller design, which has a simple analog implementation, has been verified with a dual-load experimental contactless system. [ABSTRACT FROM PUBLISHER]

A multiple-output dc–dc converter with shared zero-current-switching (ZCS) lagging leg is presented in this paper. In this proposed converter, each output is regulated by the phase shifted between the independent leading legs and the shared lagging leg. The switches in the leading legs process the individual output power and work in zero-voltage switching (ZVS), which are suitable for utilizing the MOSFETs; the switches in the shared lagging leg process the total output power and work in ZCS, which especially suit for using the insulated gate bipolar transistor. The ZVS of the leading legs is easy to achieve and the ZCS of the lagging leg is independent of the loads. Therefore, the proposed converter has compact structure, fully regulation abilities, adapted soft-switching modes, and simple modulation schemes. Moreover, the new outputs can be conveniently obtained by using the uniform algorithm. In this paper, the derivation of the proposed converter is presented; the proposed shared ZCS lagging leg converter with dual output is analyzed, and the analysis is further extended to the general multiple-output situation; the state variation of the proposed converter is also surveyed; finally, a three-output prototype with 200–240 V input, 24 V/5 A, 15 V/15 A, and 12 V/10 A outputs is built, and the analysis is verified by the experimental results. [ABSTRACT FROM AUTHOR]

Emerging feature dense portable microelectronic devices pose several challenges, including demanding multiple supply voltages from a single miniaturized power-efficient platform. Unfortunately, the power inductors used in magnetic-based switching converters (which are power efficient) are bulky and difficult to integrate. As a result, single-inductor-multiple-output (SIMO) solutions enjoy popularity, but not without design challenges. This brief describes, illustrates, and evaluates how SIMO dc-dc converters operate, transfer energy, and control (through negative feedback) each of their outputs. [ABSTRACT FROM AUTHOR]

This paper focuses on the control strategy of a multiple-output active-clamp forward converter devoted to PC power supplies. The primary- and secondary-side switches of the forward converter are driven by dedicated ASIC units. In detail, regulation of the main-switch duty-cycle is achieved by a primary IC implementing feed-forward control, while the outputs of the converter are locally regulated by two ASICs independently from the primary-switch duty-cycle. Since no communication is required during normal mode, the duty cycle is defined by the the primary IC which controls the main switch in such a way that the primary duty-cycle is larger than the secondary one. A peak overall efficiency higher than 90% at 50% load has been obtained in normal operative conditions. During stand-by mode, communication between the primary controller and the secondary ones is however required to increase the low-power-mode efficiency. The working principle of the proposed converter is described in detail both in normal and stand-by mode. Several experimental results are carried out to validate the approach discussed throughout this paper. [ABSTRACT FROM AUTHOR]

The molten iron quality (MIQ) in the blast furnace (BF) needs on-site sampling and laboratory tests, which is very unfavorable to the control. To estimate multiple molten iron quality indicators (MIQIs) such as molten iron temperature (MIT), silicon content ([Si]), phosphorus content ([P]) and sulfur content ([S]) in real-time, some data-driven multi-input multi-output (MIMO) modeling methods have lately been developed. However, those modeling methods ignore the inter-indicator correlation. Moreover, the above modeling methods do not consider the processing strategy for the samples with missing indicators. To conquer the above two problems in the process of modeling, this paper proposed an output space transfer based MIMO Takagi–Sugeno (T–S) fuzzy modeling method for the four MIQIs. Through sparse learning of the correlation matrix, the inter-indicator correlation is specifically modeled. Due to the full use of inter-indicator correlation, the impact of missing indicators on modeling accuracy is greatly reduced. An effective alternative optimization algorithm is also provided for the corresponding intractable optimization problem. The actual data test shows that the proposed method can greatly improve the accuracy of multiple MIQIs estimations. [ABSTRACT FROM AUTHOR]

Orthogonal-design-based space-time (ODST) codes of size (n×n) offer maximum diversity gain advantage and a simple yet optimal decoding algorithm under an arbitrary signal alphabet or constellation A. However, these designs only exist for n=2, 4, 8 when A is real and for n=2 when A is complex. In this letter, we address the question of the existence of ODST codes of other sizes when A is restricted to be a proper subset of either real or complex numbers. We refer to these as restricted-alphabet ODST (RA-ODST) codes. We show that real RA-ODST codes of size greater than 8 that also guarantee maximum diversity advantage do not exist. Without the diversity requirement, RA-ODST codes exist only when A={a,-a}, 0