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The paper aims to design of dual-mode boost converter with integrated low-voltage control circuit is introduced in this paper. The paper aims to discuss these issues.

The converter is operated either with LC filter or with charge pump circuit by the switch control. The control stage with error amplifier, comparator, and oscillator is designed with the supply voltage of 3.3 V and the operating frequency of 5.5 MHz. The compensator circuit exploits a pole compensation for a stable operation.

The simulation test in 0.35 μm CMOS process shows that the charge pump regulator and DC-DC boost converter are accurately controlled with the variation of number of stages and duty ratio. The output-voltage is obtained to be 6-15 V within the ripple ratio of 5 percent. Maximum power consumption is about 0.65 W.

This dual-mode is useful in the converter with a wide load-current variation. The advantage of the dual-mode converter is that it can be used in either high or low load current with a simple switch control. Furthermore, in charge pump regulator, there is no degradation of output voltage because of the feedback control circuit.

The purpose of this paper to ensure the rapid developments in the radio frequency wireless technology, the synthesis of frequencies for pervasive wireless applications is crucial by implementing the design of low voltage and low power Fractional-N phase locked loop (PLL) for controlling medical devices to monitor remotely patients.

The developments urge a technique reliable to phase noise in designing fractional-N PLL with a new eight transistor phase frequency detector and a good linearized charge pump (CP) for speed of operation with minimum mismatches.

In applications for portable wireless devices, by proposing a new phase-frequency detector with the removal of dead, blind zones and a modified CP to minimize the mismatch of currents.

The results are simulated in 45 nm complementary metal oxide semiconductor generic process design kit (GPDK) technology in cadence virtuoso. The phase noise of the proposed Fractiona-N phase locked loop has–93.18, –101.4 and –117 dBc/Hz at 10 kHz, 100 kHz and 1 MHz frequency offsets, respectively, and consumes 3.3 mW from a 0.45 V supply.

THE CONSTANT SPEED DRIVES supplied by Sundstrand which convert the variable speed of a jet engine into a constant speed to drive a 400Hz constant frequency electric generator to provide power for an aircraft's electrical system were first introduced in 1945 and allowed aircraft to use a lighter weight, more economical, and more reliable ac generating system.

THE transportation of material in bulk containers over the past few years has increased until the variety of loads carried is infinite, indeed even the casual road user cannot have failed to notice the increasing numbers of tank carrying vehicles ; everything from concrete to flour is now accepted as normal. Labour is one of the heaviest charges in industry today and here perhaps is the main reason for the change ; handling any material by hand carries with it a premium in labour costs with loading and unloading and often double and treble handling. As is often the case when economic reasons cause readjustment of industrial methods other advantages also come to light, e.g. delivery of flour in bulk is cleaner and less wasteful than carrying in sacks. The same can be said for most other materials.

This paper aims to set out a vision of the advent of autonomous electric vehicles (AEV), piloted by artificial intelligence and serviced by other “intelligent” machines, a scenario that poses vast implications for business strategy in many industries.

Given the speed with which business leaders today must assess and react to the business risks and opportunities engendered by breakthrough technological change, their plans to navigate an autonomous electric vehicle-based transportation future can benefit from a scenario map to the roadblocks and the richest prospects.

Self-driving electric cars and trucks, which are expected to transform the transportation landscape over the next decade. A smart charging grid is a critical technology development.

Business opportunities to transform ground transport in areas such as operations and supply chain management are significant as well, particularly with unsupervised AEVs, which could slash labor costs and transport times.

AEVs are expected to free up more than 30 billion hours per year in the U.S. alone currently spent driving, sitting in traffic or searching for a parking space.

Offers a look at the technology evolution needed for the AEV transportation revolution.

THE rapidly increasing electric power requirements of aircraft, together with their more arduous operating conditions, have accelerated the trend towards the adoption of 400 c.p.s. a.c. supplies as standard for general services. The point is being reached where a.c. distribution and control systems based on ground power station practice are becoming applicable to aircraft. The main advantages of a.c. over the corresponding d.c. systems are:

In complementary metal-oxide-semiconductor (CMOS) logic circuits, there is a direct square proportion of supply voltage on dynamic power. If the supply voltage is high, then more amount of energy will be consumed. Therefore, if a low voltage supply is used, then dynamic power will also be reduced. In a mixed signal circuit, there can be a situation when lower voltage circuitry has to drive large voltage circuitry. In such a case, P-type metal-oxide-semiconductor of high-voltage circuitry may not be switched off completely by applying a low voltage as input. Therefore, there is a need for level shifter where low-voltage and high-voltage circuits are connected. In this paper the multi-scaling voltage level shifter is presented which overcomes the contention problems and suitable for low-power applications.

The voltage level shifter circuit is essential for digital and analog circuits in the on-chip integrated circuits. The modified voltage level shifter and reported energy-efficient voltage level shifter have been optimally designed to be functional in all process voltage and temperature corners for VDDH = 5V, VDDL = 2V and the input frequency of 5 MHz. The modified voltage level shifter and reported shifter circuits are implemented using Cadence Virtuoso at 90 nm CMOS technology and the comparison is made based on speed and power consumed by the circuit.

The voltage level shifter circuit discussed in this paper removes the contention problem that is present in conventional voltage level shifter. Moreover, it has the capability for up and down conversion and reduced power and delay as compared to conventional voltage level shifter. The efficiency of the circuit is improved in two ways, first, the current of the pull-up device is reduced and second, the strength of the pull-down device is increased.

The modified level shifter is faster for switching low input voltage to high output voltage and also high input voltage to low output voltage. The average power consumption for the multi-scaling voltage level shifter is 259.445 µW. The power consumption is very less in this technique and it is best suitable for low-power applications.

The paper focuses on design, fabrication and characterization of electromagnetic microgenerators with integrated rectifying circuits to convert AC output signal to DC one. The work includes research on simulation of voltage-rectifying circuits, including charge pump, realization of the experimental printed circuit board (PCB) with selected electronic circuits and the execution of the final structure with integrated rectifying circuit. Measurements were performed on these circuits.

Electromagnetic microgenerators include multipole permanent magnets secured on rotor three-phase brushless direct current (BLDC) motor and planar multilayer multiple coils. These were fabricated using low temperature co-fired ceramics (LTCC) technology. In our experiment, six rectifying circuits were simulated and tested with a structure consisting of eight layers of coils and with an outer diameter of 50 mm fabricated earlier.

The microgenerator with Graetz bridge generates higher output power than the modified charge pump at the same rotary speed. However, it is less stable for the distance change between the structure and the magnets than the modified charge pump, which has more constant output power in a wider range of load resistance.

The presented electronic rectifying circuits are novel for LTCC-based electromagnetic microgenerator application. The structure with integrated rectifying circuits allows generation of electrical output power larger than 100 mW at the rotor speed of about 8,000 rpm.

This paper aims to provide a comprehensive literature review on modelling electro-osmotic flow in porous media.

Modelling electro-osmosis in fluid systems without solid particles has been first introduced. Then, after a brief description of the existing approaches for porous media modelling, electro-osmotic flow in porous media has been considered by analysing the main contributions to the development of this topic.

The analysis of literature has highlighted the absence of a universal model to analyse electro-osmosis in porous media, whereas many different methods and assumptions are used.

For the first time, the existing approaches for modelling electro-osmotic flow in porous have been collected and analysed to provide detailed indications for future works concerning this topic.

There arc few published works dealing with British aircraft sanitary systems and associated equipment and a comprehensive survey of this particular subject should not, therefore, be out of place here. In this article, a history of the development work culminating in the evolution of a modern scries of chemical closets is traced. It is shown that for equipment of this nature . simplicity of design is essential if proper mechanical functioning, satisfactory hygiene standards and good serviceability arc to be assured. Two outstanding features of the modern chemical closet are the closed flushing system, in which one of a scries of special chemical fluids is used as the circulating medium, and the external servicing arrangements. Specific closet design information is presented. Details arc also given of aircraft toilet compartment layout and of representative types of ground servicing equipment.