Comments on "Compression of the ECG by Prediction or Interpolation and Entropy Encoding"

A recent paper1 discusses prediction and interpolation for data compression of ECG. This communication points out that both methods can be viewed as linear filtering. They are therefore equivalent and give the same result in terms of the amount of data compression achieved.     

Electrical properties and chemical compatibility of PZT thick film on Ni substrates

The characteristics of Pb(Zr,Ti)O₃(PZT) thick films that were printed and fired on Ni substrates were studied. The dielectric characteristics of samples sintered at 850°C on Ni substrates could not be measured due to the formation of a NiO layer at the Ni/PZT interface. The scanning electron microscope and energy dispersive X-ray analysis of cross-sections of the PZT thick films on Ni substrates, and of a mixture of PZT and NiO powders, fired at 850°C, did not indicate the formation of secondary phases. However, the transmission electron microscopy showed around 8% solid solubility of NiO in the PZT. A new structure with a prefired, Au thick-film layer was designed in order to prevent the diffusion of the NiO to the PZT layer during sintering. The dielectric properties of the PZT layers printed and fired on the Ni substrates with the prefired Au electrode were significantly better than those of the layers on the uncoated substrate, the dielectric losses decreased from 0.23 to 0.05.     

Porous cobalt spheres for high temperature gradient magnetically assisted fluidized beds

Porous metallic cobalt spheres have been prepared as high temperature capable media for employment in gradient magnetically assisted fluidization and filtration technologies. Cobalt impregnated alginate beads are first formed by extrusion of an aqueous suspension of Co3O4 into a Co(II) chloride solution. The organic polymer is thermally decomposed yielding cobalt oxide spheres, followed by reduction to the metallic state, and densification. Cobalt beads have been produced with porosities ranging between 10 and 50%, depending upon sintering conditions. The product media have been characterized by scanning electron microscopy (SEM), nitrogen adsorption porosimetry, and vibrating sample magnetometry.     

Impact of wind generation on the operation and development of the UK electricity systems

Although penetration of wind generation may displace a significant amount of energy produced by large conventional plant, there are issues associated with the extent to which wind generation will be able to replace the capacity and flexibility of conventional generating plant. This is important since wind power is variable, so it will be necessary to retain a significant proportion of conventional plant to ensure security of supply especially under conditions of high demand and low wind. Hence, the capacity value of wind generation will be limited as it will not be possible to displace conventional generation capacity on a “megawatt for megawatt” basis. Wind power is variable and not easy to predict, hence various forms of additional reserves will be needed to maintain the balance between supply and demand at all times. Additionally, if the majority of wind generation plant is located in Scotland and the North of England, reinforcement of the transmission network will be needed to accommodate the increases in the north-south flow of electricity.     

Phase-synchroniser based on gm-C all-pass filter chain with sliding mode control

Phase-synchronisers have many applications in VLSI circuit designs. They are used in CMOS RF circuits including phase (de)modulators, phase recovery circuits, multiphase synthesis, etc. In this article, a phase-synchroniser based on g_m-C all-pass filter chain with sliding mode control is presented. The filter chain provides good controllable delay characteristics over the full range of phase and frequency regulation, without deterioration of input signal amplitude and waveform, while the sliding mode control enables us to achieve fast and predetermined finite locking time. IHP 0.25 µm SiGe BiCMOS technology has been used in design and verification processes. The circuit operates in the frequency range from 33 MHz up to 150 MHz. Simulation results indicate that it is possible to achieve very fast synchronisation time period, which is approximately four time intervals of the input signal during normal operation, and 20 time intervals during power-on.     

Preparation of ultrathin PZT films by a chemical solution deposition method from a polymeric citrate precursor

Ultrathin PZT film was prepared using a chemical solution deposition method from polymeric citrate precursors. The PZT solution was spin-coated on an amorphous silica layer formed on a Si(1 0 0) substrate. The films were thermally treated from the substrate side with a low heating rate (1°/min) up to 700 °C and finally annealed for 10 h. Ultrathin PZT films without microstructural instability were prepared in spite of high temperature and long annealing time. AFM and HRTEM investigations revealed the formation of a well-developed dense microstructure consisting of spherical crystallites (4–7 nm). Low roughness (2.2 nm) of a ～26 nm thick layer was obtained for a two-layered PZT film. The grazing incidence X-ray diffraction (GIXRD) measurements confirmed the polycrystalline structure of ultrathin PZT films. Also, GIXRD and electron energy dispersive X-ray (EDS) analysis showed that compositional variations were smaller than expected, in spite of the long annealing time.     

Investigation of direct load management scheme with consideration of end‐user comfort

A direct load management scheme with two‐way communication, with consideration of end‐user comfort, is proposed. First, the control algorithm is developed and the data required to be transmitted between system operator and controllable loads are identified. Then, the actions of controllable air conditioners and the power adjustment of dispersed generators to eliminate overloads in a substation transformer are simulated. The results indicate that the proposed load management technique performs effectively to reduce overloads on the transformer while maintaining energy consumption in each load, and the performance is improved by coordination with the output of dispersed generators. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 176(3): 19–28, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21139     

Semantische Technologien für Produktionsprozessinnovationen in der Landwirtschaft

Optimization of production processes in agriculture requires that innovation in form of efficiency enhancing devices is being continuously introduced and integrated within the production environments. This paper describes how semantic modelling, web services and automatic logical reasoning are used as system enablers for such value-adding integration in implementation of semantic-based diagnoses supporting optimization of milk production processes of dairy farms.     

Clock aligner based on delay locked loop with double edge synchronization

In CMOS multistage clock buffer design, the duty-cycle of clock is liable to be changed when the clock passes through several buffer stages. The pulse-width may be changed due to unbalance of the p- and n-OS transistors in the long buffer. This paper describes a delay locked loop with double edge synchronization for use in a clock alignment process. Results of its SPICE simulation, that relate to 1.2 μm CMOS technology, shown that the duty-cycle of the multistage output pulses can be precisely adjusted to (50 ± 1)% within the operating frequency range, from 55 MHz up to 166 MHz.