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With increasing demand of high rate of production have led to develop high speed cutting machine tool which ultimately inducing higher vibration in cutting operation. In this paper, passive control system has been explored by computational analysis to reduce chatter in turning process. Effectiveness of MLPD slots has compared with three different geometry using viscoelastic material. Computation analysis of proposed MLPD concept has evaluated with harmonic response and corresponding damping ratio has derived with half power band theory. Outcome of harmonic analysis and half power band theory conclude MLPD with spline curve is more effective to reduce vibration.

Social touch seems to modulate emotions, but its brain correlates are poorly understood. Here, we investigated if frontal power band activity in the electroencephalogram (EEG) during aversive mental imagery is modulated by social touch from one's romantic partner and a stranger. We observed the highest theta and beta power when imaging alone, next so when being touched by a stranger, with lowest theta and beta activity during holding hands with the loved one. Delta power was higher when being alone than with a stranger or a partner, with no difference between the two. Gamma power was highest during the stranger condition and lower both when being alone and with the partner, while alpha power did not change as a function of social touch. Theta power displayed a positive correlation with electrodermal activity supporting its relation to emotional arousal. Attachment style modulated the effect of touch on the EEG as only secure but not insecure partner bonding was associated with theta power reductions. Because theta power was sensitive to the experimental perturbations, mapped onto peripheral physiological arousal and reflected partner attachment style we suggest that frontal theta power might serve as an EEG derived bio-marker for social touch in emotionally significant dyads.

Purpose: To describe the demand of recent World Cup (WC) races comparing top-10 (T10) and non-top-10 (N-T10) performances using power data. Methods: Race data were collected in 1-d World Cup races during the 2012–2015 road cycling seasons. Seven female cyclists completed 49 WC races, finishing 25 times in T10 and 24 times in N-T10. Peak power (1 s) and maximal mean power (MMP) for durations of 5, 10, 20, and 30 s and 1, 2, 5, 10, 20, 30, and 60 min expressed as power to weight ratio were analyzed in T10 and N-T10. The percentage of total race time spent at different power bands was compared between T10 and N-T10 using 0.75-W·kg−1 power bands, ranging from 7.50 W·kg−1. The number of efforts in which the power output remained above 7.50 W·kg−1 for at least 10 s was recorded. Results: MMPs were significantly higher in T10 than in N-T10, with a large effect size for durations between 10 s and 5 min. N-T10 spent more time in the 3.01- to 3.75-W·kg−1 power band when compared to T10 (P = .011); conversely, T10 spent more time in the 6.75- to 7.50- and >7.50-W·kg−1 power bands (P = .009 and .005, respectively) than N-T10. A significantly higher number of short and high-intensity efforts (≥10 s, >7.5 W·kg−1) was ridden by T10 than N-T10 (P = .002), specifically, 46 ± 20 and 30 ± 15 efforts for T10 and N-T10, respectively. Conclusions: The ability to ride at high intensity was determinant for successful road-cycling performances in WC races.

In this paper, a low-cost 48V, 4kW brushless fast starter system for automotive Start/Stop (S/S) applications is presented. The design and analysis of the machine, inverter, controller and control algorithm are discussed in detail. The inverter and motor are integrated within the same assembly housing as the original brush-type starter to enable a drop-in replacement. Simulation models were used to assess the performance benefits of the brushless drive during engine AutoStart events and were compared to the conventional starting system with brush-type dc motors. Simulation results showed superior engine AutoStart performance due to lower inertia, higher torque and wider power band capability of the brushless motor, especially at higher speeds. Performance was also improved due to significantly lower rotor inertia. Finally, a prototype brushless fast starter system was built and tested and found to meet the cost, performance and packaging requirements.

Traction motors of electric vehicles require wide power band characteristics. A magnetic-geared motor has a possibility to achieve these requirements because it has passively variable magnetic flux characteristics. In this paper, the passively variable magnetic flux characteristics of the magnetic-geared motor is investigated using finite element analyses. Furthermore, a maximum torque control method for the magnetic-geared motor is proposed and investigated.

The large power requirement of current brain–machine interfaces is a major hindrance to their clinical translation. In basic behavioural tasks, the downsampled magnitude of the 300–1,000 Hz band of spiking activity can predict movement similarly to the threshold crossing rate (TCR) at 30 kilo-samples per second. However, the relationship between such a spiking-band power (SBP) and neural activity remains unclear, as does the capability of using the SBP to decode complicated behaviour. By using simulations of recordings of neural activity, here we show that the SBP is dominated by local single-unit spikes with spatial specificity comparable to or better than that of the TCR, and that the SBP correlates better with the firing rates of lower signal-to-noise-ratio units than the TCR. With non-human primates, in an online task involving the one-dimensional decoding of the movement of finger groups and in an offline two-dimensional cursor-control task, the SBP performed equally well or better than the TCR. The SBP may enhance the decoding performance of neural interfaces while enabling substantial cuts in power consumption. The 300–1,000 Hz band of spiking activity, dominated by local single-unit spikes, can enhance the decoding performance of neural interfaces.

Traction motors for electric vehicles and hybrid electric vehicles require wide power band characteristics. In order to increase the power band, field weakening control is widely used in interior permanent magnet motors.

For high speed trains running at 300km/h or more, the aerodynamic noise becomes the primary noise source. A good knowledge of the location, spectral characteristics and propagation behavior of the noise source and the corresponding methods to reduce the effect of the aerodynamic noise are of crucial necessity during the design process of the high speed train. Based on the Lighthill Analogy, the pressure fluctuation of air at the surface of the train is acquired by simulating the flow field of a CRH3 high speed train running at 200 km/h, 300 km/h, 400 km/h and 500km/h by means of large eddy simulation method. By Fourier transformation, the distribution and the spectral characteristics of the surface acoustic dipole sources are obtained. The analysis of the results shows that the aerodynamic noise of the high speed train is a broadband noise with a strong radiation power band from 50Hz to 1000Hz. The dipole acoustic power calculated by statistically averaged on train surface is found to be proportional to the sixth power of running speed of the high speed train. The first and second bogie, the inter-car gap, the air deflector of the power train and the train nose of the last wagon are the main noise sources that contain high radiation energy.

In the arena of vibration energy harvesting, the key technical challenges continue to be low power density and narrow operational frequency bandwidth. While the convention has relied upon the activation of the fundamental mode of resonance through direct excitation, this article explores a new paradigm through the employment of parametric resonance. Unlike the former, oscillatory amplitude growth is not limited due to linear damping. Therefore, the power output can potentially build up to higher levels. Additionally, it is the onset of non-linearity that eventually limits parametric resonance; hence, this approach can also potentially broaden the operating frequency range. Theoretical prediction and numerical modelling have suggested an order higher in oscillatory amplitude growth. An experimental macro-sized electromagnetic prototype (practical volume of ~1800 cm3) when driven into parametric resonance, has demonstrated around 50% increase in half power band and an order of magnitude higher peak power density normalised against input acceleration squared (293 µW cm−3 m−2 s4 with 171.5 mW at 0.57 m s−2) in contrast to the same prototype directly driven at fundamental resonance (36.5 µW cm−3 m−2 s4 with 27.75 mW at 0.65 m s−2). This figure suggests promising potentials while comparing with current state-of-the-art macro-sized counterparts, such as Perpetuum’s PMG-17 (119 µW cm−3 m−2 s4).

In this paper, a low power differential preamplifier, which amplifies the input voltage and regenerates the desired output, is presented. The preamplifier can be implemented in 0.18 μm CMOS, with 1.8 V supply voltage. By using a novel structure, a high gain, high bandwidth and low power preamplifier is obtained. To increase the bandwidth, an active inductor is designed. In order to increase the gain, crossover transistors pairs are used. In addition, the parameters of the circuit are tuned to obtain high gain in a high frequency range. Therefore, this circuit is employed as a band-pass preamplifier. By using the results of simulation with HSPICE software, the gain, gain-bandwidth product and power consumption are 41.8 dB, 12 GHz and 1.39 mW, respectively.

This paper proposes a pole change generator for a windmill. Since micro windmill systems generate power from natural energy, power generation characteristics across a wide band are necessary. However, the conventional generator, in which the open voltage is simply proportional to the rotational velocity, encounters difficulty in generating power across a wide range of rotational velocities from low to high, because of the power generation characteristics. To develop a generator with a wide power band suitable for a micro windmill, this paper proposes a technique for switching the status of the generator coil connection. To demonstrate the effectiveness of pole changing, we use a pole-changing generator with 16 coils as an example. The coils can be connected using four patterns: 16-pole series, 8-pole 2-parallel, 4-pole 4-parallel, and 2-pole 8-parallel. Theoretical and experimental studies from this point of view demonstrate that this technique is effective. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(1): 28–36, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20873

In high speed railway bridges, dynamic analysis is important because of high passing velocity and moving load at the regular intervals, and damping ratio is a major parameter to predict dynamic responses. In this paper, damping ratios were estimated by using half power band width method and extended Kalman filter according to acceleration signal conditions, and a relationship between estimated damping ratios and representative values of bridge vibration was derived. From the results, damping ratios estimated from total ambient vibration were more reliable than only free vibration part. In case of using extended Kalman filter, the estimated damping ratios varying with RMQ(root mean quad), as one of representative values of bridge vibration, have more feasible trend. Thus, it is shown that further studies on reliabilities of estimated damping ratios are needed.

This paper proposes the pole change generator for windmill. Since the micro windmill system generates power from natural energy, power generation characteristics of a wide band are necessary. However, the conventional generator, where the open voltage is simply proportional to rotational velocity, encounters difficulty in generating power across a wide range of rotational velocity from low to high, in view of power generation characteristics.To develop a generator of a wide power band suitable for micro windmill, this paper proposes a technique of switching the status of generator coil connection. To prove the effectiveness of pole changing, we assumed a pole-changing generator with 16 coils as an example. The coils can be connected by four patterns: 16-pole series, 8-pole 2-parallel, 4-pole 4-parallel, and 2-pole 8-parallel.Then, theoretical and experimental studies from this point of view demonstrate that this technique is effective.

This paper proposes a new application of power amplifiers linearization technology for concurrent Dual-band differing in power. A Broadband power amplifier is used to verify proposed application. The dual 20MHz band spacing 200MHz are test at the carrier frequency of 2.3GHz and 2.5GHz. And the dual-band's power have more than 10dB difference. When the difference is 15dB, the simplified model can achieve almost the same performance with the 2D-DPD model. Lower power band's ACPR is improved from −37.3dB to −49.5dB, and higher power band's ACPR is improved from −39.1dB to −54.2dB. Meanwhile, the simplified model saves 36% coefficients.

This paper deals with the HCC algorithm (Hill Climbing Control) to optimize the performance of Magnus wind turbines reducing the response time to reach the maximum power point (MPPT Maximum Power Point Tracking) as well as to reduce fluctuations around that point. The Magnus turbines have cylinders instead of conventional blades and its operation is based on the physical principle known as the Magnus Effect. The Magnus turbines consume power for rotating the cylinders, so the MPPT performs tracking of the net power generated by subtracting the power consumed in the electric motor to drive the cylinders. The simulation results are presented for the proposed Magnus wind turbine system with measurements of mechanical shaft power including the controlled mechanical load torque and DC servo drive (DC servo drive and brushless DC motor). This system was designed to perform optimization studies of a turbine Magnus prototype. In the proposed HCC algorithm, the negative net power band uses a fixed step increment of cylinder rotation and the other parts of the curve use an adaptive step. As the curve slope tends to zero near the maximum point, the step increment decreases, thus minimizing the oscillations around that point.

The objective of the paper is to develop methodology to analyse the impact of market-based electric heating load control on the distribution network business. In this paper, the spot market-based load control scheme is demonstrated. The main target of the paper is to illustrate the phenomenon of space electric heating load control and its impact on the distribution network. The conflict of interests between the retailer and the DSO is demonstrated. The power band pricing scheme is suggested to be one way to solve the conflict. In the future, micro generation and energy storages could also relieve the conflict. AMR data, electricity spot market prices and outdoor temperature are used in the analyses. (4 pages)

The mid-frequency (MF) component of the heart rate variability is an often used method of measuring changes in the level of mental effort during human-computer interaction. However, sometimes the exact cause of a change is not self explanatory. There are certain factors, aside from mental effort, that can influence the power level of the MF band: limb movement is one such factor. In this preliminary study, we examined the impact of relatively big arm movements on the power of the MF band. Participants played a game where they had to solve simple equations under a time pressure. In one of the conditions, they also had to raise their non-dominant hand every time they entered an answer. The analysis of our data seems to suggest that the kind of arm movements, used in the experiment, had no significant effect on the MF power. However, further exploration is required to identify what kinds of movements are capable of influencing this particular power band.

Publisher Summary A successful medium-speed engine program embracing the 200 mm bore S20, 400 mm bore ZA40S and 500 mm bore ZA50S designs was offered by Switzerland-based New Sulzer Diesel before becoming part of the Wartsila Corporation. The Sulzer S20, ZA40S and ZA50S designs, covering an output range from 460 kW to 21 600 kW for propulsion and auxiliary power duties, were released for operation on fuels with viscosities up to 700 cSt. The modern four-stroke Z-engines matured from a 400 mm bore family founded by the ZH40 two-stroke medium-speed engine, designed in the early 1960s and installed in icebreakers, ferries and cruise ships. The last ZA40S program was released with a rating of 750 kW/cylinder at 510 rev/min on a mean effective pressure of 25.1 bar and with a mean piston speed of 9.5 m/s. Six, eight and nine in-line models and V12-, 14-, 16- and 18-cylinder models covered a power band from 4500 kW to 13 500 kW. Rising demand for compact, high-output medium-speed diesel propulsion installations—particularly from cruise and ferry sectors—stimulated Sulzer to introduce in 1995 a larger bore derivative to complement the successful ZA40S engine. This 500 mm bore/660 mm stroke ZA50S design extended the power range of the program to 21 600 kW at 450 rev/min from six-, eight- and nine-in-line and V12-, 14-, 16- and 18-cylinder models. Introduced in 1988 for genset drives and small-ship propulsion, the Sulzer S20 engine was distinguished by a significantly higher stroke/bore ratio (1.5:1) than established contenders in its class.

Power amplifiers for WCDMA applications must provide competitive power efficiency at low power levels as well as at full power. This paper presents a novel approach to obtain high PAE performance over a wide power band from three power states. It uses a novel BiHEMT process to co-integrate InGaP/GaAs HBT technology with InGaAs/AlGaAs E/D-Mode pHEMT into a single process. No bias reference voltage is required. Typical ultra-low power mode quiescent current is 5 mA.

In this paper, we describe state-of-the-art low-power optoelectronic VDSL system enabling broadband access to the home over 10 km of optical fibre and up to 0.4 km of twisted pair. The cabinet/distribution point interface has a footprint of just 3 cm × 3 cm × 1 cm and consumes only ~102 mW. A DMT modulation scheme was used for system tests with full duplex downstream/upstream data rates of 62 Mb/s and 28 Mb/s respectively achieved, and up to 40 dB up/downstream channel isolation is obtained using hybrid transformers.

Birecik is a Turkish hydroelectric power plant located at the Euphrat River in the southeast of Turkey. During commissioning of the units, a vibration phenomenon was discovered, restricted to a small power band. The cone which supports the thrust bearing and which is braced against the turbine head cover started to vibrate at its natural frequency. Investigations showed the vibrations to be innocuous to the lifetime of the machine. Exhaustive vibration measurements on site pointed to hydraulic source for the vibration. Detailed flow simulations by means of computational fluid dynamics (CFD) were carried out. They permitted the detailed analysis of a variety of transient flow phenomena happening inside the machine. They revealed the presence of interblade vortices in the power and head range where the vibrations occurred. As a consequence, it was suggested to inject air downstream of the wicket gates through the head cover. In 2012, one unit of the Birecik power plant was equipped with such an air injection system. As soon as the air injection was turned on, the machine operated calmly in the small power band where vibrations had been observed before. The necessary air volume was considerably smaller than expected to be necessary for a calm operation.

As the specific power output of I.C. engines is increased, the range of engine speed over which useful torque is available is reduced. This ‘power band’ can be widened by having automatically varying valve timing, with the timing being a function of engine speed and/or load. A prototype cyclic phasing unit has been tested which successfully varies the timing of a poppet valve with opening, closing points, and the form of valve lift curve being readily varied independently. The unit is simple mechanically, but ideally one unit is needed for each valve, so principal application is likely to be on engines with a small number of cylinders. In addition to flattening the torque curve, such a unit is likely to give improved fuel consumption and lower exhaust emissions, particularly hydrocarbons.