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The purpose of chopper amplifier is to provide the wideband frequency to support biomedical signals.

This paper proposes a chopper-stabilized amplifier with a cascoded operational transconductance amplifier. The high impedance loop is established using an MOS pseudo resistor and with a tunable MOS capacitor.

The total power consumption is 451 nW with a supplied voltage of 800 mV. The Gain and common mode rejection ratio are 48 dB and 78 dB, respectively.

All kinds of real time data analysis was not carried out, only few test samples related to EEG signals are validated because the real time chip was not manufactured due to funding issues.

The proposed work was validated with Monte-Carlo simulations. There is no external funding for the proposed work. So there is no fabrication for the design. But post simulations are performed.

The high impedance loop is established using an MOS pseudo resistor and with a tunable MOS capacitor. To the best of the author’s knowledge, this concept is completely novel and there are no publications on this work. All the modules designed for chopper amplifier are new concepts.

This paper initially presents the results of the analysis of a non linear on/off control system which is capable of generating a pulse width modulation (PWM). This technique can be used to design PWM choppers that can be dedicated to regulate fluctuating power supplies (photovoltaic, wind turbines, etc.). However, since the PWM losses mainly depend on the switching frequency, thus, the determination of an optimal frequency is required. Indeed, on the one hand, we seek to operate at high frequencies to reduce the residual noise by filtering. On the other hand, there is a limitation of the switching frequency due to the physical switching elements properties. Therefore, a compromise has to be made in order to determine an optimal switching frequency that minimizes the switching power losses. The main objective of this work is to present a technique that enables to sizing the chopper parameters based on the minimizing of the switching losses. An illustrative example of the proposed technique for sizing a PWM chopper is presented.

This paper initially presents the results of the analysis of a non linear on/off control system which is capable of generating a pulse width modulation (PWM). This technique can be used to design PWM choppers that can be dedicated to regulate fluctuating power supplies (photovoltaic, wind turbines, etc.). However, since the PWM losses mainly depend on the switching frequency, thus, the determination of an optimal frequency is required. Indeed, on the one hand, we seek to operate at high frequencies to reduce the residual noise by filtering. On the other hand, there is a limitation of the switching frequency due to the physical switching elements properties. Therefore, a compromise has to be made in order to determine an optimal switching frequency that minimizes the switching power losses. The main objective of this work is to present a technique that enables to sizing the chopper parameters based on the minimizing of the switching losses. An illustrative example of the proposed technique for sizing a PWM chopper is presented.

This paper presents the analysis of a nonlinear on/off control system including a filter of a second order in the closed loop. The proposed system is capable of generating a pulse width modulation which is used to design and built up a PWM (Pulse Width Modulation) chopper dedicated to regulate fluctuating power supplies such as photovoltaic, wind turbine systems; etc. The use of the second order filter aims to compensate the output against the fluctuations of irradiation as well as the variation of the load. The study essentially focuses on determining the relationship between the pulse durations with respect to system parameters and technological requirements. The theoretical study is followed by a simulation of a DC-DC chopper.

The paper aims to develop a CAD tool power electronics converters.

Integration of knowledge base techniques with OOP paradigm. Using Visual Basis class builder, 15 classes were built to form the kernel of the tool's KB.

A knowledge‐based CAD tool was developed to ease the design of power electronics converters. It can be considered a learning aid tool too.

The knowledge base of developed tool can be expanded to accommodate large number of topologies. The GUI can be also ameliorated to a better look and interaction process.

With proper enhancements, the purpose of the developed tool can be upgraded from educational one to industrial one.

Beside the methodology, the new thing in the paper is the specificity of the application of the tool (i.e. in power electronics).

The purpose of this paper is to introduce methods for calculating steady‐state and transient processes in a symmetrical three‐phase matrix‐reactance frequency converter (MRFC). The MRFC in question makes it possible to obtain a load output voltage much greater than the input voltage.

MRFCs based on a matrix‐reactance chopper are used for both frequency and voltage transformation. The processes in a MRFC system are described by nonstationary differential equations. A two‐frequency complex function method is proposed for solving non‐stationary equations in steady‐state. The method is applied to a state‐space averaged mathematical model used in the analysis of the discussed MRFC. A two‐frequency matrix transform is proposed for solving non‐stationary equations. This method can be used to find both transient and steady‐state processes.

The two‐frequency complex function method permits the reduction from 12 non‐stationary differential equations to four stationary differential equations. The two‐frequency matrix transform allows the transformation of non‐stationary differential equations to stationary ones. By using these methods descriptions of steady‐state and transient properties of buck‐boost MRFCs are obtained.

A new method of solving of nonstationary differential equations is presented. The method is useful for process analyses in nonstationary power electronic converters.

Kemutec, which includes such well‐known names as KEK‐Gardner and Mucon, supplies powder handling, processing and control equipment to many industries worldwide, including important installations for powder and resin production. The integration and installation of individual pieces of equipment is backed by the Kemutec Process Systems engineering facility. Applications engineering and trials are able to make use of one of the most comprehensive test facilities of its type in the world, which will shortly see the completion of a major expansion programme to integrate Gardner mixers and blenders, coinciding with the formation of KEK‐Gardner.

IN the two years since the last Farnborough Air Show was held by the Society of British Aerospace Companies the aircraft industry has achieved an almost complete metamorphosis from the body blows in the form of major programme cancellations that almost felled it in 1965 to the very healthy position that it holds today.

Automated chopper gun trajectory planning (CGTP) for spray forming is highly desirable for today's automotive manufacturing. Generating chopper gun trajectories for free‐form surfaces to satisfy material distribution requirements is still highly challenging due to the complexity of the problems. In this paper, a user‐friendly software for automated CGTP has been developed. The CGTP software can take different formats of the CAD models of parts. A chopper gun trajectory is generated based on the CAD model of a part, chopper gun model, and constraints. A part is partitioned into patches to satisfy the given constraints. A trajectory integration algorithm is developed to integrate the trajectories of the patches to form a trajectory for the part. The CGTP software has been tested by Ford Motor Company and achieved satisfactory results.

This paper seeks to address the question: what happened to postmodern?

Three trends are reviewed: postmodern fragmentation, late modern appropriations of postmodern moves; and emergent awareness of the dark‐side of postmodern.

On the way to postmodern theory the revolution to reform modern capitalism fragmented into rhetoric‐strands, while practice became ineffective.

The paper concludes with possibilities for participatory research in ways that enact more postmodern forms of capitalist praxis.

It is suggested that qualitative studies of postmodern praxis can be conducted; such as postmodern organizations that enact the dark‐side of biotechnology; consumer organizations, such as Blackspot and No Sweat that contract to non‐sweatshop factories; and autoethnographic examples of how building a Harley‐Davidson chopper is post‐production and post‐consumption.

The paper shows that in the fragmentation of moderns and postmoderns, there is a relentless appropriation of postmodern moves by late modernism. This is one contributing factor to the “dark side of postmodern.” Other contributing factors are naive brands of postmodern (e.g. chaos theory, complexity, new age spirituality) which, sometimes only see the positive potentialities, and blind one to the dark side. What is original is the call for a combination of critical theory and postmodern theory (critical postmodern) that looks at the relation between various ideas of modern and postmodern and how they can be studied in their dialogicality.