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The article provides an overview of the Krell KMA-i800 monoblock power amplifier, which incorporates Krell's iBias technology and was designed by engineer Dave Goodman. The article emphasizes the amplifier's features, such as its power output, low distortion, and control over speaker drivers. The author shares their personal listening experience with the amplifier, noting its warm and full sound. Technical details about the amplifier's design and performance are also provided. The article concludes that the Krell KMA-i800 amplifiers are highly regarded and recommended for audiophiles. [Extracted from the article]

The article provides information on the patent application "Systems and Methods for Power Control for a Therapeutic Tool," filed by the inventors including Tachi Callas, Marc S. Kreidler and Maw-Lin Kuo on February 23, 2024 and was made available online on August 29, 2024. The patent application is assigned to MAQUET Cardiovascular LLC. Also mentioned are inventors' summary information for the patent application and the claims supplied by the inventors.

A research study conducted by Universiti Pertahanan Nasional Malaysia examined the effectiveness of using direct current video (e-DC) to improve learning outcomes and motivation in physics education. The study involved 183 pre-university students and found that the use of e-DC led to significant improvement in students' understanding of the topic of Direct Current (DC). Additionally, the majority of students reported that the learning process became more engaging and fun with the use of e-DC, and they felt motivated in learning physics. This study highlights the potential benefits of incorporating digital technologies into the learning process, particularly in the context of online education during the COVID-19 pandemic. [Extracted from the article]

A patent application has been filed for a radio frequency (RF) receiver system used in magnetic resonance imaging (MRI). The system includes an RF receive coil with a detune circuit that uses crossed diodes to measure the electrical current and determine the proper function of the diodes. This helps ensure safe operation and prevents damage to the coil. The system also includes a controller that can send a signal to the MRI system if there is an incorrect function of the diodes. The invention eliminates the need for an additional fuse and allows for the detection of faults in the PIN diodes. A software package is also provided for controlling the RF receiver system. [Extracted from the article]

This paper presents a double-isolated dc-dc converter exploiting integrated LC galvanic barriers. The converter consists of only two dice both fabricated in a 0.35- $\mu \text{m}$ BCD technology with a thick-oxide back-end for 5-kV galvanic isolation. It uses a novel architecture to transmit power and the control feedback signal across two double isolation barriers, which are performed by integrated isolation capacitors and transformers. A resonant mode operation for the isolation networks is exploited to boost efficiency with respect to traditional converter schemes based on series-connected isolation components. Measurements of the dc-dc converter at 3.3-V power supply demonstrate 100-mW dc output power with a power efficiency of 16.8% at a regulated output voltage of 3.3 V. [ABSTRACT FROM AUTHOR]

"According to some embodiments, the control circuit comprises a device for detecting the rotation speed of the motor, and the control and command unit is configured to determine the delay time in which to activate the switch device as a function of the speed detected. "According to the invention, the control circuit for direct current motors comprises a switch device and a device for detecting the zero-crossing of the supply voltage. "Furthermore, thanks to the effect given by the combination of the inertia of the motor and the electricity in it, the electric voltage on the motor remains substantially stable even in the half-wave in which the motor is not powered. [Extracted from the article]

In situ synchrotron X-ray radiography was used to study the effect of direct current (DC) on the grain nucleation and growth of Sn-50 wt.%Pb alloy. The results showed that applying DC adequately during solidification could effectively enhance the grain nucleation and inhibit its growth. Imaging of comparative experiments with varying DC intensity indicated that the final grain size, determined by the competition between grain nucleation and growth, was sensitively dependent on the DC intensity. It was found that the average grain size was decreased from 1632 to 567 μm with DC density of 1.5 A/mm 2 compared to the case without DC. Beyond this value, raising the current density may cause a significant decrease in the nucleation rate, and thus lead to a coarsening of the grain structure. [ABSTRACT FROM AUTHOR]

This paper deals with the analysis of the convergence properties of the max-consensus protocol in presence of asynchronous updates and bounded time delays on directed static networks. The work is motivated by real-world applications in distributed decision-making systems, for which max-consensus is an effective paradigm. The main result of this paper is that the strongly connectedness of the directed communication network is a sufficient condition for the asynchronous max-consensus protocol to let a distributed system converge in finite time. Implementation issues are also taken into account, by complementing the theoretical analysis with the definition of a mechanism to detect convergence in a distributed fashion. Finally, a numerical example is given, highlighting both the issues related to the failure of synchronous protocols applied to asynchronous settings and the effectiveness of the proposed asynchronous framework. [ABSTRACT FROM AUTHOR]

The Holomorphic Embedding Loadflow Method is extended here from AC to DC-based systems. Through an appropriate embedding technique, the method is shown to extend naturally to DC power transmission systems, preserving all the constructive and deterministic properties that allow it to obtain the white branch solution in an unequivocal way. Its applications extend to nascent meshed HVDC networks and also to power distribution systems in more-electric vehicles, ships, aircraft, and spacecraft. In these latter areas, it is shown how the method can cleanly accommodate the higher-order nonlinearities that characterize the I-V curves of many devices. The case of a photovoltaic array feeding a constant-power load is given as an example. The extension to the general problem of finding DC operating points in electronics is also discussed, and exemplified on the diode model. [ABSTRACT FROM AUTHOR]

This paper addresses the stability issue of dc distributed power systems (DPS). Impedance-based methods are effective for stability assessment of voltage-source systems and current-source systems. However, these methods may not be suitable for applications involving variation of practical parameters, loading conditions, system's structures, and operating modes. Thus, for systems that do not resemble simple voltage-source systems or current-source systems, stability assessment is much less readily performed. This paper proposes an impedance-based criterion for stability assessment of dc DPS. We first classify any converter in a dc DPS as either a bus voltage controlled converter (BVCC) or a bus current controlled converter (BCCC). As a result, a dc DPS can be represented in a general form regardless of its structure and operating mode. Then, the minor loop gain of the standard dc DPS is derived precisely using a two-port small signal model. Application of the Nyquist criterion on the derived minor loop gain gives the stability requirement for the dc DPS. This proposed criterion is applicable to dc DPSs, regardless of the control method and the connection configuration. Finally, a 480 W photovoltaic (PV) system with battery energy storage and a 200 W dc DPS, in which the source converter employs a droop control, are fabricated to validate the effectiveness of the proposed criterion. [ABSTRACT FROM AUTHOR]

The paper is concerned with the problem of input-to-state stability (ISS) for nonlinear delay systems with large delay periods (LDP). The concepts of the length rate of LDP and the frequency of LDP are introduced. First the considered system is converted into a switched delay system which may include an unstable subsystem. Then based on a piecewise Lyapunov functional, the ISS properties of the systems are developed under the constraints of the length rate and the frequency of LDP. ISS for a special kind of nonlinear delay systems is also considered and the conditions of nonlinear matrix inequalities (NLMIs) are proposed to guarantee the ISS properties of such a system. A numerical example and an example of a series DC motor are given to show the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

The gain/phase imbalances and DC-offsets in the in-phase and quadrature branches in direct conversion transmitters (DCTs) are main sources of errors, especially at microwave frequencies and above. These impairments distort the spectrum of the transmitted signal and degrade the communications performance. In this paper, a blind technique based on higher order statistics is proposed to estimate the calibration parameters in order to compensate for these impairments. By minimizing a cost function composed of second and fourth moments of the modulator output signal, the DC-offsets, gain imbalance, and phase imbalance can be successively calibrated. The convergence of the proposed technique is also analyzed. This technique is blind in the sense that it does not require any prior knowledge about the DCT input signal, and is applicable to many communications systems including QAM, OFDM, and SC-FDMA. Computer simulations and experiments at 20 GHz demonstrate that the proposed technique can significantly improve the DCT performance in terms of local oscillator leakage and image suppressions. [ABSTRACT FROM AUTHOR]

The article focuses on the circuit assemblies of electric vehicle (EV) and hybrid electric vehicle (HEV) and galvanic isolation. It notes that the five main circuit assemblies of EV/HEV battery management systems include on-board charger, direct current (DC/DC) converter, and auxiliary inverter. Moreover, galvanic isolation insulates functional sections of electrical systems to avoid current flow between the sections while allowing energy or information to be exchanged between the sections.

The problem of combining interleaved operation of several identical power converters with a hysteretic control is solved in this paper by inducing a sliding regime to all inductor currents in a ring configuration. No external synchronizing signal is required. The sliding-mode approach in a boost converter-based parallel association with a ring configuration for the current control guarantees the desired averaged value of all currents and also provides asymptotic stability. In addition, a detailed analysis to derive the phase displacement of each inductor current and to obtain the value of the resulting switching period in steady state is presented. The analysis takes into account the delay introduced by the filter in the hysteretic control loop of each converter, and the delay caused by the semiconductor turn-on and turn-off. Simulation and experimental results are reported for two and three interleaved converters showing a perfect agreement with theoretical predictions. [ABSTRACT FROM PUBLISHER]

The paper considers the following worst-case steady-state tolerance analysis problem: given a linear dc circuit whose resistors and sources have preset tolerances, determine the range of the electrical power consumed in the circuit. It is shown that the power range sought can be computed as the range of an associated interval linear programming problem. A method for solving the latter problem is suggested whose numerical complexity is not a priori exponential. A numerical example illustrating the new method is provided. [ABSTRACT FROM PUBLISHER]

The article provides strategies on how to tweak the features of a microcontroller (MCU) to enhance the resolution of an embedded alternate/direct current or A/D converter (ADC) with the use of the MAXQ2010 software. It examines the frequency-domain transfer function of a multibit ADC and its signal-to-noise ratio. It provides several programming source codes concerning the adjustment of resolutions such as 14 bits on the channel 0 of ADC. It explores the modules and registers of the MCU.

This paper investigates the coexisting fast-scale and slow-scale bifurcations in simple dc/dc converters under peak current-mode control operating in continuous conduction mode. Our focus is the boost converter as it is a representative form of dc/dc converter requiring current-mode control. Effects of varying the input voltage and some chosen parameters on the qualitative behavior of the system are studied in detail. Analysis based on a nonlinear simplified discrete-time model, which takes into account the effects of parasitics, is performed to investigate the coexistence of fast-scale and slow-scale bifurcations, and to identify the different types of bifurcation. Boundaries of stable region, slow-scale bifurcation region, fast-scale bifurcation region, coexisting fast and slow-scale bifurcation region are identified. Experimental measurements of the boost converter are provided for verification of the analytical results. [ABSTRACT FROM AUTHOR]

The article offers suggestions for inspecting alternating current (AC) and direct current (DC) electrical systems in a vessel. It highlights the role of marine electrician in familiarizing the standards and recommendations from the organization National Fire Prevention Association (NFPA) and the American Boat and Yacht Council (ABYC) boat builders. It also mentions that inspection includes battery, electrical panels and wiring.

Shows how to arrange four diodes and a plain transformer to generate pulsating direct current (DC). Limitations of a microphone input for each channel for amateur musicians; How to make relaxation oscillator; Finding defective stage of radio or audio amplifier; Circuitry of switchless intercom.

The article offers step-by-step instructions for making a remote-controlled aircraft based on Arduino and 433NHz RF modules controlling a brushless direct current (DC) and servo motors.

The article investigates an extra-high-tension (EHT) power supply that has a capability of delivering variable direct current (DC) voltage using high power silicon-controlled rectifiers (SCRs). The generation of SCR triggering pulses synchronised with the input sine waves is regarded as the most significant design aspect of the circuit. It is inferred that the circuit may be extended to high values of voltage and load currents. The circuit and construction of the project is provided.

This article focuses on how to wire a model railroad for Digital Command Control (DCC). Wiring a DCC-equipped layout is a bit different than the wiring for conventional direct current cab control. Because a DCC system controls multiple trains, a lot more power is needed than most conventional power packs provide, and this requires some extra attention to safety, including using heavier-gauge wire and circuit breakers. To help prevent damage as a result of the short circuit, a DCC booster is equipped with a built-in high-speed circuit breaker that shuts off power to the track. Poor performance is another consequence of inadequate wiring. Nickel-silver rail is a poor conductor compared to copper wire, and over long runs where power is carried exclusively by the track, the nickel-silver can cause a significant drop in available voltage for the trains.

Introduces the iPowir technology products, a synchronous high-current direct current (DC)/DC building block in a multi-chip module, by International Rectifier Corp. Compatibility; Architecture of the iPowir.

Studies the low-power Direct Current (DC) uninterruptible power supply (UPS) which keeps the DC equipment running during power failures. General organization of a simple UPS; Information about the low-power DC UPS prototype; Techniques in checking and testing the system before powering it up. INSET: Parts list for the low-power DC ups..

The article reports on the direct-current (d.c.) research project by the engineers from Bonneville, Idaho for the long-distance electric power transmission under the alternating currrent (a.c.) standards, where the 235-mile, 220,000-volt circuit between Grand Coulee and Bonneville dams is considered as one of its longest a.c. lines.

Attenuators ease the design of high dynamic range receivers and instrumentation. [ABSTRACT FROM AUTHOR]

The article gives suggestions on factors to be kept in mind while making selection for components for solar photovoltaic (PV) systems specially PV modules and inverters. Emphasis on connection technology needs to be given in terms of its potential to minimise loss. Faulty connection of DC plug connectors during installation pose a risk in the system. Care should be taken that components clear the standards as set by the regulatory authority.

The article discusses technological developments to increase the energy efficiency of high-voltage DC power lines as of 2013. Topics include the use of AC lines in integrated grid networks and electricity systems, the development of a high-voltage DC circuit breaker by the Swiss conglomerate ABB, and renewable energy sources.

The article talks about the oldest and the first recorded use of an energy-rich geologic anomaly in the form of a hot spring outdoor pool made outside a house in Iceland. Topics discussed include technical feasibility in transmission of high voltage direct current transmission via undersea cable, concerns of enlarging hydropower capacity for export, and interconnectors resulting in ceding control over an important sector of economy.

The article offers the author's insight on railroad switches and direct current circuit (DCC). He conducts test layout for this through a stall-motor switch machine using a DCC decoder. He points out that Kato power pack contains switch extensions that controls two switches at the same time. He explains that block-protection and signaling does not require automated switching.

In this article, the author discusses his decision to switch from Molex type connectors to Anderson Powerpoles for direct current (DC) connectivity. He explains the complexity of using the Molex system, mentioning such factors as cost, time consumption, and inconvenience. Information on the correlation between the resistivity of metals and Powerpole pins is also presented.

The article evaluates several model locomotives equipment including Navigator direct current curcuits (DCC) system, Navigator Handheld, and Navigator Receiver from ESU LLC.

The article offers information on how to properly wire reversing sections of digital command control (DCC). It says that any method that can be used in controlling a reversing section on a direct current (DC) layout can be used with a DCC as it also contains a polarity like a DC. It mentions that an auto-reversing module is another method to control reversing sections as it relies on the occurrence and detection of short circuit.

The article reviews the pin-compatible 5-ampere (A) ISL8205M and 3A ISL8202M single-channel direct current to direct current (DC/DC) step-down power modules from Intersil Corp.

The article announces the release of the LPRV2300 dual band photoreceiver and discusses the features of Direct Current (DC) coupled response functionality.

Provides information on BWR-5/3.3 series of dual-output direct current (DC)/DC converters which feature load polygon circuitry for current sharing. Architecture; Features; Price.

The article offers brief information on DC power supplies Keithley Series 2260B and signal generator series AFG1062 from Tektronix Inc.

The article offers brief information on the LV UltraMOVTM Varistor Series from Littelfuse which will provide circuit protection solution for DC voltage application.

The article offers brief information on the OKLP-X/60-W12A-C 60 A Power Block DC (direct current)-DC converter solution from Murata.

Details two accidents in the United States Navy involving air-conditioning condensers and direct current (DC) plugs involving a shore-steam system. The two sailors involved in the incidents; How each accident happened; The damage they caused; How each incident could have been avoided.

The article offers information on the OTDC, a direct current circuits, from ABB.

The article offer brief information on two 1200 Watt Multi-Range Direct Current (DC) Power Supplies including model 9115-AT and 9116 for Automotive and Automatic Test Equipment (ATE) applications from B&K Precision Corp.

The article provides information on the MGJ2 series of 2 Watt high isolation dual output Direct Current (DC)/DC converters from Murata Power Solutions Inc. including its suitability or powering high and low side gate drivers in bridge circuits using insulated-gate bipolar transistors (IGBT).

The article discusses the release of the two ultra-compact alternating current-direct current (AC-DC) frontend power supplies from Emerson Network Power and outlines the features of the electronic equipment.

The article previews the LT3791 synchronous buck-boost direct current to direct current (DC/DC) light-emitting diode (LED) driver and voltage controller from Linear Technology.

The article features ZL2105, a single-chip 3-amp power integrated circuit manufactured by Zilker Labs Inc. in Austin, Texas. The product can integrate full digital power management capabilities. It combines a synchronous stepdown controller with drivers, voltage tracking, sequencing and margining blocks, voltage, current and temperature monitoring, including fault detection circuitry. The devices can be monitored and controlled individually or as a system.

The article features the International Rectifier's 1R3094, a three-phase pulse width modulation control integrated circuit with integrated drivers suited for 80-amp direct current/direct current converter applications. The IR6678 synchronous MOSFET, which features a typical on

The article reviews three direct-current (DC) power options for Internet Protocol (IP)-based devices such as Wireless Access Points, Voice Over IP phones, and IP security cameras. The three DC power choices discussed are the use of a data switch or patch-bay with built-in Power Over Ethernet, an alternating current (AC)-to-DC power supply located in a wiring closet or an AC-to-DC hardwired transformer located in an electric box near the device.