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In this paper, the influence of the stiffness and damping of real elastic shafts on the behavior of a multidrive system driving a tissue paper machine is investigated. The drive system consists of four dc motors, where two of them drive the Yankee drying cylinder and the other two drive the presses section. Six-pulse thyristor bridge power converters that are connected to the same power transformer supply the motors. The inertias of the motors and the driven machines, in conjunction with the shaft stiffness, form mechanical resonators. Thus, resonance phenomena may occur, which may lead to undesirable results. This particular case results to two three-mass and one five-mass systems. This paper presents an analysis of the resonance frequencies of two sections of the machine during startup and machine production, considering the shaft stiffness (shaft diameter, length, and thickness). The elastic shafts eliminate the ripple of the motor electromagnetic torque, which is transferred to the driven machine. The behavior of elastic shafts with different stiffness in the transmission system is studied. Moreover, the steady state and dynamic behavior of the system considering the influence of the elastic shafts and vibration analysis were investigated using simulation. A model algorithm for system simulation was developed using the MATLAB/SIMULINK software. Characteristic simulation results are presented and are expressed in terms of speed and torque response. Considering the resonance frequency analysis and simulation results, mechanical design guidelines can be given for the most significant drive components in order to avoid torsional oscillation resonance phenomena and minimize torsional oscillations of the drive system. [ABSTRACT FROM AUTHOR]

Multiwalled carbon nanotubes (MWNTs) are characterized at X-, Ku-, Ka-, and Q-bands by rectangular wave- guide measurements. The scattering parameters (S-parameters) of thin MWNT papers containing a large ensemble of randomly oriented nanotubes are measured by a vector network analyzer from 8 to 50 GHz. A rigorous extraction algorithm has been developed to compute the effective complex permittivity (ϵ = ϵ′ - jϵ″) and permeability (μ = μ′ - jμ″) of the nanotube papers from the measured S-parameters. The extracted effective medium parameters are verified by finite-element simulations using Ansoft's High Frequency Structure Simulator (HFSS). The uncertainties for this characterization method are analyzed. The systematic uncertainties are found larger at lower frequencies than at higher frequencies. The extracted conductivity of the nanotube papers is in the range of 810-1500 S/m and the dielectric constant is from 250 to 700. The extracted complex permittivity can be fitted with the Drude-Lorentz model for the 8-50-GHz frequency range. The effective medium theory is then applied to remove the impact of air in the nanotube paper. [ABSTRACT FROM AUTHOR]

Conventional ultrasound probes have inherent limitations in some application scenarios. Because of their fixed shapes and sizes, they can hardly pass through small orifices to examine the target closely. With the recent development of microelectromechanical systems and flexible electronic technologies, collapsible and self-assembling devices are being considered as a potential approach to address this problem. This article presents an innovative transformable ultrasonic transducer (TUT), which can transform between a one-dimensional (1-D) linear array and a 2-D planar array with the ability of switching between different functions including 2-D/3-D imaging and high-intensity focused ultrasound beamforming. The transforming process is accomplished with a specially designed flexible printed circuit board inspired by a paper-folding mechanism. The electrical and acoustic properties of the developed transducer along with the acoustic field distribution in its different forms have been characterized. The 2-D/3-D imaging performances of the TUT have been also evaluated under 1-D and 2-D configurations, respectively. In addition, the performance of a focused concave transforming mode has been also discussed. The evaluation results suggest that TUT can maintain its performance under different structures with precise transforming control. The TUT device has the potential to considerably expand the applications of industrial and clinical ultrasound. [ABSTRACT FROM AUTHOR]

Focuses on optimal approach to fault tolerant software system design.

The article presents invitation for posters and papers for the 2013 IEEE International Reliability Physics Symposium (IRPS) to be held in Monterey, California from April 14-18, 2013. Among the areas where papers should be focused include electronic systems, automotive reliability, and circuit aging simulation. It notes the awards to be given by IRPS including Outstanding Paper, Best Student Talk, Best Poster, and Best Paper.

Packaging radio-frequency microelectromechanical systems (RF-MEMS) is mandatory for their integration in electronic systems. This paper discusses the integration of a Au−Ru/AlCu contact in a MEMS fabrication process with a wafer-level packaging (WLP) step through Al−Ge eutectic bonding. The Au contact is embedded in a movable fixed−fixed beam made of $30 ~ \mu \text{m}$ thick Si while Ru is used as a coating metal on top of the AlCu static electrode. The measured return loss and isolation of the contact, up to 40 GHz, are $\geq -1.7$ and $\leq -12$ dB respectively. The WLP Au−Ru/AlCu contact has an electrical resistance $\leq 1.2 ~ \Omega $ up to 3 million cycles in hot switching at 0.1 W before failing due to high electrical resistance. Au hillocking is identified as the only intrinsic limiting mechanism that can be mitigated by an appropriate design rule. It is demonstrated that Au−Ru/AlCu is a promising contact configuration, compatible with Al−Ge eutectic bonding, and can be integrated in a standard MEMS fabrication process flow for the development of a robust generation of WLP RF-MEMS. [ABSTRACT FROM AUTHOR]

It is well known that a priority for Communications Society (ComSoc) is to increase the activity in Chapters and student branches and to support initiative projects. One of the projects of the Tomsk Chapter is the annual All-Russia Student Paper Contest on Information Security, based on IEEE (Institute of Electrical and Electronics Engineers) rules, which was successfully held for the third time in April 2003. In connection with the establishment of the Siberian IEEE Section in February 2003, this contest was the first event in the Section with technical support from ComSoc. The suggestion to start the contest came from the Tomsk Chapter Chair, who motivated Tomsk State University of Control systems and Radioelectronics to start this crusade.

These instructions give guidelines for preparing papers for this publication. [ABSTRACT FROM AUTHOR]

We present simple, practical codes designed for the binary and Gaussian dirty-paper channels. We show that the dirty-paper decoding problem can be transformed into an equivalent multiple-access decoding problem, for which we apply superposition coding. Our concept is a generalization of the nested lattices approach of Zamir, Shamai, and Erez. In a theoretical setting, our constructions are capable of achieving capacity using random component codes and maximum-likelihood decoding. We also present practical implementations of the constructions, and simulation results for both dirty-paper channels. Our results for the Gaussian dirty-paper channel are on par with the best known results for nested lattices. We discuss the binary dirty-tape channel, for which we present a simple, effective coding technique. Finally, we propose a framework for extending our approach to general Gel'fand-Pinsker channels. [ABSTRACT FROM AUTHOR]

The International Computer and Software Applications Conference has celebrated its tenth anniversary in 1986. The conference has been very successful in attracting excellent papers and panels from both academia and industry. It continued the tradition and attracted superb papers for the following tracks: software quality, software engineering, software requirements, development environments, software techniques and knowledge-based systems.

In this paper, we propose a sensitivity-enhanced thermoreflectance microscopy (TRM) system employing an electronic auto-balancing photoreceiver for effective thermal fault localization through a Si substrate. The proposed system in the auto-balanced detection not only improves the system signal-to-noise ratio (SNR) by approximately five times compared to that achievable via normal detection but also mitigates the inherent system noise, such as pseudothermoreflectance signals, by using the optical zooming. Moreover, temperature variations as small as ~47 mK were detectable under the measurement conditions employed in this paper. Finally, we experimentally demonstrated clear localization of a thermal fault, which was dimly visible in the normal backside detection results, in an optical zoomed thermal image. [ABSTRACT FROM AUTHOR]

There is an on-going need for faster, more accurate, and easier to implement threat identification systems for concealed electronics, to thwart terrorism and espionage attempts. Common electronics are used in the design of improvised explosive devices (IEDs), targeting military, and civilian populations, while concealed recording devices steal proprietary/confidential data, compromising both government and industrial resources. This paper discusses a novel, nonintrusive, repeatable, reliable, expandable, and simple-to-implement detection and identification (D&I) system for identifying threats by using unintended radiated emissions (URE). This paper differs from current URE proposals, by avoiding energy radiation. The proposed process also addresses big data problems involved in capturing and building databases of URE characteristics. Issue interpretation is utilized with URE data to distinguish between threat/nonthreat devices using multiple criteria decision analysis and other decision-making techniques to determine model and mode of hidden devices. System optimization, verified by testing, is used to improve the speed and accuracy of the identification algorithm. The system is developed with data from 130 devices and validated with 33 separate devices, which are representative of IED and espionage threats. Due to slow progress in the URE D&I field, the properties and potential of a more effective D&I system, compared to current methods, will be of interest to the explosive ordnance disposal, security services, electronic systems manufacturing, automated inventory, mobile application development communities, and potentially others as well. For a field that is not well documented, this paper provides a clear, concise, and detailed model for future research and applications of URE D&I. [ABSTRACT FROM AUTHOR]

This paper proposes a new methodology for automated design of power electronic systems realized through the use of artificial intelligence. Existing approaches do not consider the system's reliability as a performance metric or are limited to reliability evaluation for a certain fixed set of design parameters. The method proposed in this paper establishes a functional relationship between design parameters and reliability metrics, and uses them as the basis for optimal design. The first step in this new framework is to create a nonparametric surrogate model of the power converter that can quickly map the variables characterizing the operating conditions (e.g., ambient temperature and irradiation) and design parameters (e.g., switching frequency and dc link voltage) into variables characterizing the thermal stress of a converter (e.g., mean temperature and temperature variation of its devices). This step can be carried out by training a dedicated artificial neural network (ANN) either on experimental or simulation data. The resulting network is named as $\text{ANN}_{1}$ and can be deployed as an accurate surrogate converter model. This model can then be used to quickly map the yearly mission profile into a thermal stress profile of any selected device for a large set of design parameter values. The resulting data is then used to train $\text{ANN}_{2}$ , which becomes an overall system representation that explicitly maps the design parameters into a yearly lifetime consumption. To verify the proposed methodology, $\text{ANN}_{2}$ is deployed in conjunction with the standard converter design tools on an exemplary grid-connected PV converter case study. This study showed how to find the optimal balance between the reliability and output filter size in the system with respect to several design constraints. This paper is also accompanied by a comprehensive dataset that was used for training the ANNs. [ABSTRACT FROM AUTHOR]

Impulse Radiating Antenna (IRA) is a highly efficient antenna that has a number of applications in both civilian and military sectors. These antennae produce fast rising pulses in a narrow beam that can give rise to high intensity electromagnetic fields having a wide impact on electrical and electronic systems. One such area where the impact becomes prominent is the present day telecommunication network. This system consists of buried coaxial cables connected to sensitive equipments at their terminations. Henceforth, there could be situations where the incident IRA field can interfere with the cables laid in the area. As the cables pass over different regions with varied soil texture and characteristics, the proportion of the IRA field incident on it will vary, that is dependent upon the nature of the soil in which the cable is buried. This paper reports the response of different types of soils to incident IRA fields and the induced voltage in a cable buried in such soils. A case study of different types of soils is also included in the paper. It is found that the soils in industrial areas are more prone to electromagnetic interference from IRA rather than in a highly moist ground. [ABSTRACT FROM AUTHOR]

To improve the comfort and user acceptance of the intelligent vehicle braking system, this paper proposes a control strategy for the electronic brake booster (Ebooster) that considers differences in driving behaviors. First, a real-vehicle driving data collection platform is built to collect the driving behavior data of 84 drivers under typical vehicle-following braking conditions. Subsequently, the k-means clustering algorithm optimized by particle swarm optimization (PSO) is used to realize the cluster analysis of driving behaviors, and the support vector machine (SVM) algorithm optimized by the genetic algorithm (GA) is used to complete the identification of driving behaviors. Next, through the analysis of the boost characteristics of the self-designed Ebooster, driving behaviors are matched with boost characteristics, and a personalized basic boosting control strategy based on the driver behavior is designed. Finally, a hardware-in-the-loop (HiL) bench and a real-vehicle test platform are designed and built to verify the effectiveness of the personalized control strategy of the Ebooster. The results show that this method can effectively identify the type of driver and make personalized adjustments to the basic boosting strategy of the Ebooster, which effectively improves the personalization of the braking system, resulting in a higher pedal response and user acceptance. [ABSTRACT FROM AUTHOR]

Radar radio source (RRS) recognition plays an important role in the fields of military electronic support systems (ESM) and civilian autonomous driving. The rapid development of machine learning technology, especially deep learning, has effectively and efficiently improved RRS intelligent recognition performances when operating in the increasingly complex electromagnetic environment. However, the data sampling limitation and computation cost are still severe challenges in real RRS recognition scenarios. In this paper, we propose a novel network based on meta-transfer learning, called RRSARNet, to achieve effective adaptive RRS recognition in the context of low signal-to-noise ratio (SNR). First, by using the short-time Fourier transform, a six-type small samples RRS simulation dataset with different SNR levels is constructed. Then, a novel RRSARNet, based on metric learning, is proposed, which consists of a four-layer embedding module and a four-layer relational module. Finally, the RRS dataset is divided into training, supporting and testing subsets, which are used to train and test the RRSARNet in a meta-transfer learning method. Experiments on the RRS dataset show that the proposed RRSARNet can achieve an overall accuracy (OA) above 96% and 99% when the SNR is above −15 dB and −10 dB, respectively. Even when the SNR is -30 dB, OA can reach more than 70%. For 5-way 1-shot and 5-way 5-shot experiments, the inference time of an image is about 0.043 and 0.140 milliseconds, respectively. Besides, experiments on the RRS simulation dataset and the two benchmark datasets, the RRSARNet performs better or more competitive than many existing state-of-the-art technologies in terms of recognition accuracy. [ABSTRACT FROM AUTHOR]

Large portions of a winder's control system software are tested during commissioning. This is inefficient because production is stopped and financial pressures limit the time available for testing. However, it avoids the cost of integrating the winder and electrical drive system before installation. This paper describes a winder simulator that allowed control system software to be tested before installation. Shipping roll build up, parent roll build down, mechanical brakes, and a two-drum windup model were developed. These models were used to simulate the winder, web, and drive system dynamics in real time with a dedicated programmable logic controller (PLC). This PLC provided signals for the winder PLC that would normally be supplied by the drive system and various sensors. The simulator was verified with data from a previously installed winder. The use of the simulator before installation of a new winder demonstrated the benefits of pre-installation software testing. [ABSTRACT FROM AUTHOR]

This article reports that the Cypak company has developed a disposable paper computer that can collect, process, encrypt, and store up to 32 kilobytes of data. The Cypak's system contains printable sensors and a small multipurpose application-specific integrated circuit with a radio-frequency identification interface. It detects events or accepts input via graphite-ink circuits. Thus, if a user breaks a seal to remove a product or presses a surface to answer a question, the system recognizes whether the circuit is opened or closed and records the information.

High precision register controls are indispensable in roll-to-roll (R2R) printing systems for mass manufacturing. In R2R printing systems, each gravure cylinder is driven by an individual motor and guiding rolls distributed between two adjacent gravure cylinders are driven by the tension of their wrapped web. In the speed-up phase, tension fluctuations caused by torque balance of guiding rolls generate register errors in each printing unit. Therefore, it is a challenging issue to design a control method to reduce the register errors. In this paper, a mechanical model of R2R printing systems in the speed-up phase is developed based on the principle of mass conservation and torque balance. A model-based feed-forward proportion-derivative controller is designed to reduce the register errors caused by the tension fluctuations. The validity of the proposed method is demonstrated by simulation and experiments carried out on an industrial rotogravure printing press. A comparison with other control methods especially a well-tuned proportion differential control which is widely adopted by printing presses shows that the absolute maximum register error is drastically reduced and the average register error is greatly decreased by the proposed method. The results verify the effectiveness and feasibility of the proposed control method. Note to Practitioners—This paper presents control strategy for the speed-up phase in R2R printing system, particularly for printing systems with electronic line shafts. Few existing systematic research is relevant with the speed-up phase in the R2R printing system. This paper analyses the relationship of the register error and the web tension fluctuations between two adjacent gravure cylinders which are driven by the guiding rolls, then proposes the control strategy based on the identification of the acceleration of guiding rolls. The proposed method can be extended to other similar R2R systems. Simulation and industrial experiments suggest that the control method is feasible and has superior performance compared with the existing methods. In the future research, we will study the adaptive model representing the acceleration of guiding rolls in different R2R web systems. [ABSTRACT FROM AUTHOR]

This paper presents an average dwell-time method for fault-tolerant control of a class of uncertain switched linear time-delay systems and also designs an algorithm to determine the parameters pertaining to the dwell-time condition. Compared to the literature results, this paper features the following: 1) the proposed method is independent of switching polices if switchings are slow enough in the average sense; 2) the proposed control design guarantees exponential stabilization of this class of time-delay linear systems with actuator faults; and 3) this method treats all actuators in a unified manner without a need to identify which are faulty or healthy actuators. The proposed method is applied to the water pollution control problem, for the first time, to deal with different ratios of stream flow rates to effluent flow rates. [ABSTRACT FROM AUTHOR]

Information about upcoming events of interest to Computer Society members. [ABSTRACT FROM PUBLISHER]

This paper presents a joint typicality framework for encoding and decoding nested linear codes in multi-user networks. This framework provides a new perspective on compute–forward within the context of discrete memoryless networks. In particular, it establishes an achievable rate region for computing a linear combination over a discrete memoryless multiple-access channel (MAC). When specialized to the Gaussian MAC, this rate region recovers and improves upon the lattice-based compute–forward rate region of Nazer and Gastpar, thus providing a unified approach for discrete memoryless and Gaussian networks. Furthermore, our framework provides some valuable insights on establishing the optimal decoding rate region for compute–forward by considering joint decoders, progressing beyond most previous works that consider successive cancellation decoding. Specifically, this paper establishes an achievable rate region for simultaneously decoding two linear combinations of nested linear codewords from $K$ senders. [ABSTRACT FROM AUTHOR]

This paper considers a distributed storage system, where multiple storage nodes can be reconstructed simultaneously at a centralized location. This centralized multi-node repair (CMR) model is a generalization of regenerating codes that allow for bandwidth efficient repair of a single-failed node. This paper focuses on the tradeoff between the amount of data stored and repair bandwidth in the CMR model. In particular, repair bandwidth bounds are derived for the minimum storage multi-node repair (MSMR) and the minimum bandwidth multi-node repair (MBMR) operating points. The tightness of these bounds is analyzed via code constructions. The MSMR point is characterized by codes achieving this point under functional repair for the general set of CMR parameters, as well as with codes enabling exact repair for certain CMR parameters. The MBMR point, on the other hand, is characterized with exact repair codes for all CMR parameters for systems that satisfy a certain entropy accumulation property. Finally, the model proposed here is utilized for the secret sharing problem, where the codes for the multi-node repair problem are used to construct communication efficient secret sharing schemes with the property of bandwidth efficient share repair. [ABSTRACT FROM AUTHOR]

A passive compressive device (PCD), which works at millimeter waves, is proposed in this paper. In a passive manner, the device allows to compress the signals from multiple separate channels into a single or a reduced number of channels. This permits a simplification of the transmitter or receiver chains for radar imaging applications. The PCD is a 3-D cavity that ensures each channel to be decorrelated with each other. If the transfer functions are known, the compressed signals are decompressed in postprocessing. This paper proposes a suitable method to estimate simultaneously the transfer functions of the PCD. This is validated by measurements in a multiple-input-multiple-output (MIMO) configuration to produce a complex synthetic aperture radar image. Measurements revealed that the point spread function generated by the MIMO configuration with the use of the PCD leads to almost similar results, in terms of spatial resolution and sidelobe level ratio, as those of a single-input-multiple-output configuration (uniform amplitude), with a fewer receiving elements. [ABSTRACT FROM AUTHOR]

Focuses on the advantages of an electronic system Manuscript Central, a state-of-the-art Internet-based reviewing process. Adoption of the service by the Institute of Electrical and Electronics Engineers; Capability of the system in enabling the entire peer-review process to take place online; Introduction of temc.manuscript central.com Web site.

In a recent Special Section published in IEEE Transactions on Consumer Electronics we introduced smart electronics. We presented a set of papers which were selected after rigorous review with a scope of artificial intelligence (AI) or machine learning (ML) approaches used for various levels of system abstractions, from device-level to system-level. In one school of thought energy-smart, security-smart, and response-smart are 3 dimensions of smart electronic systems. [ABSTRACT FROM AUTHOR]

This paper discusses challenges and opportunities for thermal management of information and communications technologies equipment, with a particular focus on telecommunications equipment. This paper identifies the key drivers for network traffic growth and how these increasing traffic demands are driving innovations in telecommunications, requiring the development of new and novel thermal management technologies to meet the product performance and reliability requirements. Application areas discussed include photonics, wireless networking, extreme heat density applications, and liquid cooling, with spatial scales ranging from individual transistors up to data center and telecom central offices. A perspective on the anticipated technology trends, key technical challenges, and opportunities for innovation and impact is also presented. [ABSTRACT FROM AUTHOR]

Star trackers are autonomous, high-accuracy electronic systems used to determine the attitude of a spacecraft. In recent years, commercial-off-the-shelf (COTS)-based star trackers are growing in importance for low-cost and short-duration missions, but their fault tolerance against soft errors has not been studied in detail. In this paper, we propose a self-healing system protected with ad hoc techniques that can be used as the first step to implement a fault-tolerant COTS-based star tracker for smallsat applications. [ABSTRACT FROM AUTHOR]

Continuous cardiac monitoring using electrocardiograms (ECG) provides a range of patient information, essential for making clinical decisions, to healthcare providers. Unfortunately, the clinical standard of ECG recording requires the use of rigid metal electrodes, conductive gels, and wired electronic devices, which often cause skin injuries and health risks for pediatric patients with underdeveloped, fragile skin. Here, we introduce a wireless, soft, comfortable electronic system that obviates the need for skin preparation, electrolyte gels, or aggressive tapes. The low-profile device incorporates a thin-film circuit and nanomembrane sensors, encapsulated in a hyperelastic elastomer. The soft elastomeric membrane offers an optimized adhesion that ensures a conformal lamination of stretchable electrodes on the skin for recording of high-fidelity biopotentials. The combined set of on-board Bluetooth module, front-end amplifier, and voltage regulator enables a real-time, long-range, wireless monitoring of physiological data, including ECG, heart rate (HR) and respiratory rate (RR). A pilot study with pediatric patients demonstrates the clinical feasibility of the device as a comfortable, reliable biopotential monitor, suggesting a new standard for safe and effective pediatric care. [ABSTRACT FROM AUTHOR]

Modern electronic systems are performing more and more safety-critical tasks, whereby a robust communication is crucial. To protect those communication channels, error detection and correction codes (EDCCs) are widely used. The very construction of an EDCC has an impact on the resiliency against electromagnetic interference. Within this paper, the effectiveness of several EDCCs is assessed and compared. It is found that the effectiveness depends on the ratio between the channel's bit rate and the frequency of the incoming disturbance. Specific focus is being given to incorrect data perceived as correct: false negatives. Each of the considered EDCCs has an increased vulnerability for false negatives at bit rates that have a specific ratio to the disturbance frequency. The main cause behind this is the repetitive or alternating bit patterns within the codes themselves. Finally, foundations are laid to develop codes that are as robust as possible against harsh electromagnetic disturbances. [ABSTRACT FROM AUTHOR]

This correspondence considers communication over two Gaussian channels with additive state interference anti noiseless output feedback-the multiple access channel (MAC) and the augmented broad- cast channel (ABC) (a special class of the physically degraded broadcast channel). The state interference is assumed to be available noncausally at the transmitters. Deterministic coding schemes for these two channels were suggested by Ozarow when there is no state present. Recently, Merhav and Weissman derived an optimal feedback coding scheme for the single-user Gaussian channel with additive state interference. Combining ideas from these two schemes, we extend Ozarow's coding algorithms to the state-dependent case, showing that the capacity regions of the MAC and the ABC are not affected, even though not all parts of the system have knowledge of the state. The proposed schemes attain a better error performance and reduce the coding complexity with respect to the standard random binning coding technique. [ABSTRACT FROM AUTHOR]

The safety and reliability of inverters play a significant role in stable power electronic system operations. Considering a railway vehicle air-conditioning inverter as a case study, this paper presents a generic open-circuit fault diagnosis method that can be applied to various inverter and control schemes. First, a detailed model of three-phase output currents under both normal and fault status is derived, and then the concept of space trajectory is introduced based on the three-phase output currents. The open-circuit faults of the inverter lead to output phase current distortion. Therefore, different types of faults have different space trajectories, and the corresponding shape of the space trajectory is considered to be a fault feature. Then, the fault is located by the direction vector and center-of-mass coordinate. The effectiveness and reliability of the diagnosis method are verified and analyzed using a hardware-in-the-loop test platform. [ABSTRACT FROM AUTHOR]

An in situ colored dissolved organic matter sensor based on a frequency spectrum shifted maximum-length sequence (FSSM) modulation method was proposed in this paper. The energy behavior resulting from the direct maximum-length sequence (m-sequence) modulation method was analyzed. We found a kind of twice modulation method, which optimizes m-sequence frequency spectrum structures. This novel method can effectively reduce the energy loss caused by filtering and reduce the noise introduced by demodulation. The sensitivity of the developed sensor was improved to an unprecedented level by optimizing the modulation/demodulation scheme without increasing the light-emitting diode intensity. Subsequently, we developed a cost-saving hardware sensor which can meet the requirements of the in situ measuring system with the FSSM modulation method. The equivalent input noise current of the electronic system can be as low as 12.20 fA. The limit of detection (LOD) of the sensor reached a maximum of $0.0168 \mu \text {g/L}$ within a concentration range of 0– $3000~\mu \mathrm {g/L}$ , and with an R-squared value of 0.9967. The results demonstrated that the LOD of our sensors was fivefold higher than the LOD of commercially available chromophoric dissolved organic matter (CDOM) sensors and doubled its normal detection range. The sensor also exhibited excellent anti-interference ability and it can attenuate sunlight and electromagnetic interference by up to ten times while improving the stability of the system. The improvement of the CDOM sensor’s performance is of great significance to the marine environmental information monitoring field. [ABSTRACT FROM AUTHOR]

The real-time simulation based on the field programmable gate array (FPGA) is receiving more and more attention. However, up to now, the simulation scale for the power electronic system is not so satisfactory due to the real-time requirement and the FPGA resource limitation. This paper proposes a sub-microsecond level real-time simulation method for microgrids. The power converters are modeled with fixed-admittance models and simulated with a compact electromagnetic transients program (EMTP) algorithm. In the meanwhile, the distribution lines/cables are modeled with π-circuit models and simulated with a distributed circuit solution method, called the latency insertion method (LIM). As a result, the distribution generation (DG) systems are decoupled with each other and can be simulated in parallel. The case study shows that the proposed simulation method consumes much fewer FPGA resources compared with the traditional one. Besides, the time step can be much smaller and doesn't need to increase with the simulation scale. With these advantages, the real-time simulation of a microgrid consisting of three three-phase converters, three boost circuits and 21 three-phase lines can be achieved on the Xilinx Kintex-7 410T FPGA with a minmum time-step of 380 ns. [ABSTRACT FROM AUTHOR]

Designing of power electronics converters seldom considers multiscale coupling relationship between components and circuits. Although macroscale is computationally efficient, it barely contains the micro implications about aging, deterioration, transient performance, etc. Conversely, the microscale obtains multiple observation scope, however, with computational disaster. In this paper, the multiscale method is applied in the power electronic modeling which provides a qualitative methodology to combine the scales appropriately, and to obtain the dynamic response under the action of multiphysics accurately. Firstly, the concept of multiscale and the scale division of power electronic system are expounded. Considered the dynamic behavior of components and converters with different complexity, the framework of multiscale converters and modeling method is proposed. Afterwards, a scalable coupling separation method is presented, providing interfaces for the multiphysics and dielectric physics. Additionally, a multiscale conversion algorithm considering both efficiency and accuracy is designed. In the end, a DC/DC converter is taken for the verification. The feasibility and advantages of multiscale method and conversion algorithm have been demonstrated in accuracy, consistency and multiple analysis. By filling in the microscale observation, it is plausible to provide theoretical guidance for reducing margin, accurate analysis and reliability estimation of electronic components. [ABSTRACT FROM AUTHOR]

Rapid voltage changes (RVCs) are power quality (PQ) events characterized by small and fast transitions between two steady-state root-mean-square (rms) voltage levels. RVCs occur quite often at the distribution level and are expected to be even more frequent in the future due to the increasing penetration of dynamic loads and renewable-based generators in the smart grid. Unlike other PQ events, RVCs are less critical, but also more difficult to detect than dips/sags and swells, due to their smaller voltage variations. Nevertheless, they can be harmful to generators’ control systems and electronic equipment in general. Moreover, they strongly affect flicker. The IEC Standard 61000-4-3:2015 clearly describes an algorithm for RVC detection. However, this approach is poorly characterized in the scientific literature. In fact, it suffers from some drawbacks. In this paper, some of them (e.g., rate-dependent detection limits and detection delays) are analyzed in depth. In addition, an alternative approach based on the estimation of the rate of change of rms voltage is proposed. Multiple simulation results show that the approach considered is more sensitive to noise, but also faster, especially when not so fast RVCs occur. Moreover, it allows measuring the rate of change of rms voltage, which is currently disregarded in the IEC Standard. [ABSTRACT FROM AUTHOR]

Modern power systems face several problems at frequencies above the range of traditional stability studies due to the increasing penetration of power electronic devices. This phenomenon has been recently referred to as electromagnetic transient stability and is a growing issue in systems with power electronic converters at any power and voltage level, such as FACTS, high-voltage DC, interfaces for grid connection of renewable energies, custom power devices for power quality enhancement, among others. The study of power systems stability is usually carried out by simulation tools that represent the power system through phasor models. However, due to the faster dynamics of modern systems, the harmonic interaction among the controllers, converters, and electric power components, recent research results suggest that some stability analyses should be conducted with models suitable for wider frequency ranges, e.g., electromagnetic transient models. This paper reviews the use of frequency domain methods to analyze the influence of the modeling approach of passive power components on the results of electromagnetic transient stability studies. [ABSTRACT FROM AUTHOR]

Due to the ever increasing complexity of hardware systems, designers strive for higher levels of abstractions in the early stages of the design process. Modeling hardware at the electronic system level (ESL) is one way to address this demand, with the C++-based system modeling framework SystemC and its abstract communication library transaction level modeling (TLM) having become de-facto standards for ESL system design. While the C++ compiler is sufficient to compile and simulate a given ESL design, for tasks of design understanding, debugging, or validation (where access to the details of design’s structure and behavior is necessarily required), design needs to be processed by an appropriate tool. This problem is often solved by adding instrumentation code to either the design or the library, usually resulting in incomplete logs, work overhead and/or incompatibilities. This paper introduces an approach that automatically extracts information about both, structure and behavior of SystemC designs and TLM transactions, nonintrusively. The information is retrieved from a given design by running it in debug mode while being connected to a preprogrammed debugger, thus leaving the existing sources and workflows untouched while collecting a vast amount of data without user intervention. Illustrating use cases, value change dump files of the SystemC models’ behavior and unified modeling language activity diagrams of transaction protocols are created automatically from simulation runs. [ABSTRACT FROM AUTHOR]

Capacitive dc-links are widely used in voltage source converters for power balance, voltage ripple limitation, and short-term energy storage. A typical solution, which uses aluminum electrolytic capacitors for such applications, is assumed to be one of the weakest links in power electronic systems, therefore, also becoming one of the lifetime bottlenecks of power electronic systems. Various passive and active capacitive dc-link solutions have been proposed intending to improve the reliability of the dc-links qualitatively, making great effort to diverting the instantaneous pulsating power into extra reliable storage components. In this paper, a generic topology derivation method for single-phase power converters with active capacitive dc-link integrated has been proposed, which can derive all existing topologies, and identify a few new topologies. According to the synthesis results, the main achievements in research on capacitive dc-link solutions are reviewed and presented chronologically as well as thematically ordered. Furthermore, the reliability-oriented design procedure is applied to size the chip area of active switching devices and the passive components to fulfill a specific lifetime target and system specification, as well as compare the overall capacitive energy storage, energy buffer ratio, and the cost of different solutions. The cost comparisons are performed with a scalable lifetime target and power rating. It reveals that different conclusions can be drawn with different lifetime targets in terms of cost-effectiveness. [ABSTRACT FROM AUTHOR]

FlexRay offers high-speed reliable transmission in the vehicle domain. Thus, it is one of the most popular in-vehicle communication protocols for the applications that are safety-critical or applications with very low transmission time requirement. Due to the real-time constraint, the worst case end-to-end delay (EED) for such applications transmitting over a shared bus must be known. This paper addresses the problem of computation of EED for a given set of tasks with precedence constraint and corresponding messages, which are scheduled with slot multiplexing for event-triggered communication over the dynamic segment of FlexRay. First, computing precise delay has been shown to be an intractable problem. Subsequently, motivated by the intractability, an efficient estimation technique has been proposed to compute approximate EED. Unlike the common practice of considering the network in isolation, we present a comprehensive timing analysis, which considers the effects of task execution as well. Moreover, EED is allowed to be greater than interactivation time of task graph. The extensive simulation has been performed on the test cases generated with uniform as well as normal distribution. Note to Practitioners—In the past few decades, due to the large-scale use and sophistication of automotive electronic systems, various in-vehicle communication networks and protocols are also evolving. FlexRay is one such in-vehicle communication protocol, which provides the mechanism for the fault-tolerant high-speed communication over FlexRay bus. FlexRay is widely being employed for safety-critical applications in the automotive domain. For such applications, often the timing constraint is imposed with a bound on the worst case EED. Thus, timing properties of the designed network must be verified before applying it on the real domain such that the worst case EED for the propagation of an event at sensor end to actuator end is known. The proposed estimation technique can be used to compute approximate EED for an application scheduled with other applications over the dynamic segment of FlexRay. In addition, various guidelines for designing the network in order to reduce overestimation have also been presented. [ABSTRACT FROM AUTHOR]

Active cancellation of disturbing signals is a common method in electromagnetic compatibility (EMC) of power electronic systems. In this paper, a new method of suppressing periodic disturbances is extended and applied. In this method, the disturbing harmonics are suppressed by a synthesized cancellation signal that is synchronized with the converter's operation. Here, the cancellation signal is synthesized from a number of destructive sine waves. The appropriate amplitudes and phases are found via a convenient and robust adaptive approach. As a special feature of this method, many troublesome effects, like delays or complex frequency characteristics, can be compensated easily. Therefore, this method does not suffer from the same limitations as previous active techniques. Until now, the method has only been proven for a small number of harmonics. In this study, it is applied to a wide frequency range of 150 kHz to 30 MHz of a 48-/12-V dc/dc converter, e.g., for automotive applications. An optimization strategy is developed from a causal model of the system. A test setup is realized, and the sensor's and injector's performances are discussed regarding the automotive EMC standard CISPR 25. Measurement results for the artificial network and the antenna are presented. The additional power losses are estimated. [ABSTRACT FROM AUTHOR]

A simple multiplier for the estimation of the maximum power yield of a solar panel may be realized with a pulsewidth modulator working as analog multiplier circuit. Though the output of the pulsewidth modulator multiplication is not proportional to the actual output power of the solar panel, it may be shown that its maximum follows the maximum of the power curve of the panel. The multiplier allows a complete analog implementation of the maximum power point tracker of the panel thus keeping the simplicity needed in robust electronic systems. This paper presents the working principle of the maximum power point regulator, its design procedure, and a practical implementation for a low power solar panel, 7.1 V and 487 mA, used in small satellite platform applications. [ABSTRACT FROM AUTHOR]

High-density, point-of-load (PoL) power conversion and power delivery are required to continue scaling electronic systems with increased functionality, more bandwidth, and smaller sizes. To meet the demands of these highly complex and miniaturized electronic systems, new 3-D integration schemes of advanced passive and active components are needed to enable the next-generation power distribution networks (PDNs). In addition, shorter interconnect lengths are required to provide low losses and better transient response in switch-based power conversion systems. Tantalum capacitors have the potential to provide some of the highest volumetric densities of any current capacitor technology, but are generally bulky components with low frequency stability, limiting their use in future 3-D power systems. In this paper, a process for the embedding and integration of ultrathin, high-density tantalum capacitors with improved frequency stability is demonstrated. The 5-V capacitors show a density of $1~\mu \text{F}$ /mm2 at 1 MHz with only a 100- $\mu \text{m}$ thickness, and are shown to be capable of direct integration on silicon for short interconnect length of $ < 100~\mu \text{m}$. The electrical performance of the capacitors is tested after integration and shows that they retain high capacitance density and low equivalent series resistance (ESR), while also providing low leakage currents. The combination of low loss, high volumetric density, and 3-D integration capability make the capacitors an ideal candidate for next-generation power modules. [ABSTRACT FROM AUTHOR]

Information about upcoming events of interest to Computer Society members. [ABSTRACT FROM PUBLISHER]

In this paper, a size-compact and monolithically integrated millimeter-wave 16-way high-power combiner for advanced radio-frequency (RF) electronics applications is developed featuring a wide operational bandwidth and high isolations between the combiner's adjacent ports. The proposed combiner is operating at the X band and is composed of fifteen 3-dB directional coupler units that are properly configured to achieve the overall structural compactness. The combiner is fast-prototyped as a single part by employing a metallic three-dimensional (3-D) printing technique, which successfully overcomes the difficulty in its monolithic implementation by using conventional subtractive manufacturing techniques. The experimental results demonstrate that the 16-way power combiner achieves an approximately 21% operational bandwidth (8.5–10.5 GHz) at the X band with port isolations of more than 20 dB, an amplitude imbalance of about ±1 dB, a phase deviation of around ±1°, and good return and insertion losses. The excellent RF performance of the combiner makes it a good candidate for applications in multiport high-power electronics systems where highly efficient power transmission and conversion among different ports are required. [ABSTRACT FROM AUTHOR]

Accurate position estimation is an integral part of any motion control system. Besides, instantaneous position of poles plays an important role in electronic drive system of modern PM machines. Resolvers, due to their structure, are the most reliable position sensors in harsh environments. However, resolvers are not as accurate as optical encoders in normal conditions. To increase the accuracy of these sensors, various solutions are used, such as optimization in winding arrangement, rotor and stator contour, slot–pole combinations, and improvements in resolver-to-digital converter. In this paper, fractional slot concentrated winding is used in an axial flux resolver. By the aid of winding function approach, it is shown that increasing the coil pitch improves the estimated position accuracy. The theory is tested for double-layer and four-layer windings with different displacement angles. A new double-stage resolver is also introduced. The proposed structure, in which a meta-heuristic algorithm determines the slot dimensions, the number of turns, and the displacement angle between the stages, results in lower total harmonic distortion of output voltage and, consequently, lower estimated position error. The theoretical and analytical expressions are verified by a three-dimensional time stepping finite element analysis and experimental results. Good agreement between simulation and experimental results validate the advantages of the optimized resolver. [ABSTRACT FROM AUTHOR]

Electromagnetic interference filters are broadly used in power electronic systems in order to respect electromagnetic compatibility normative constraints, which considerably increase overall cost and volume mainly because of the common-mode (CM) inductor. In this paper, a new method to calculate the optimal volume of the CM inductor is proposed. It takes into account core saturation issues that may greatly impact inductor volume and filter performances. Consequently, it is shown that in some cases, increasing the inductance value up to the best value can significantly reduce the filter volume in addition to further enhancing the filter attenuation. It is also shown that different nearly-best inductor geometrical parameters with different shape factors can be obtained, which provides an important degree of freedom to designers while introducing the filter in the energy conversion system. [ABSTRACT FROM AUTHOR]

Modular multilevel-cascaded converter-based STATCOMs are scalable to higher voltages without requiring a step-up transformer with multiple windings and can be realized using a low switching frequency, giving lower harmonic content and, hence, a reduced filtering requirement. This paper presents a new injection technique to extend the operating ranges of modular multilevel-cascaded converters STATCOMs when used for negative sequence and reactive current compensation. A nonsinusoidal voltage or current containing a fundamental and its third-harmonic component is injected to achieve phase cluster voltage balance. This technique reduces the maximum dc-link voltage for the star configuration, and the maximum converter phase circulating current for the delta case, compared to applying only sinusoidal zero-sequence components for mitigating the same degree of load unbalance. The analysis is confirmed experimentally, showing that the third-harmonic injection can allow a significant improvement of STATCOM capability for simultaneous compensation of unbalanced load and reactive current. [ABSTRACT FROM AUTHOR]

The topic of designing sequence set with good correlation properties has received considerable attention due to its numerous applications in many active sensing and communication systems. For example, a multiple-input multiple-output radar system transmits orthogonal waveforms or zero correlation zone sequences to achieve a long virtual aperture, which results in enhanced parameter identifiability and improved resolution. However, it is difficult to design sequence set with accurately controlled correlation properties due to numerous nonconvex and highly nonlinear inequality constraints. In this paper, new sequence set design methods, based on the local integrated sidelobe level and the local peak sidelobe level metrics, are proposed to tackle the optimization problems under the nonconvex and nonlinear inequality constraints to meet the correlation requirements. Numerical examples are provided to show the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

In a low-angle target parameter estimation scenario, the backscattered signals from targets are often distorted due to clutter and multipath, which significantly degrades the performance of direction-of-arrival (DOA) estimation. In general, the backscattered multipaths are modeled as coherent signals with respect to the direct path. Decorrelation algorithms such as spatial smoothing and matrix reconstruction can mitigate the effect of multipath. However, most of these methods will perform poorly or even fail for solving parameter estimation problem of low-angle targets in complex terrain where there are rich multipath scatterings. This paper presents a novel method that combines time reversal (TR) technique, coherent signal-subspace method (CSM), and multiple signal classification algorithm to perform DOA estimation in a low-angle target scenario. The TR technique takes advantage of multipath echoes recorded by a sensor array and adaptively adjusts TR probing waveforms to increase the signal-to-noise ratio in a rich scattering environment. Moreover, the CSM method compresses the energy of a signal into a predefined subspace to exploit the full time-bandwidth product of signal sources and cope with coherent wavefronts. As a result, the proposed new DOA estimation algorithm outperforms significantly the conventional methods. The Cramer–Rao bounds analysis and numerical simulations commendably validate the accuracy and robustness of the proposed method. [ABSTRACT FROM AUTHOR]