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This paper presents an original maximum power point tracking controller for an experimental direct-drive full-variable-speed full-rated converter Type IV Wind Energy Conversion System in standalone operation. Specifically, we propose and implement in a real-time platform a novel reverse-acting controller that is strongly aimed at obtaining reliable and efficient experimental results to extract maximum power from the wind. Since our approach is focused on the experiments, we purposely derive a concise control law that can easily be implemented using a standard digital processor. Our initiative is presented as an alternative to some recent and valuable proposals that are based on detailed models that may be difficult to implement. An open-loop steady-state analysis is also presented in order to demonstrate the reverse-acting relationship between the input and output of the system to be controlled.

The PWM update is inevitably delayed one sampling period due to the time-consuming calculation of the digital processor, the delay time products a severe phase and amplitude error in output voltage when the PMSM is running at high speed and the carried ratio is insufficient, affecting the stability of the high-speed PMSM sensor-less drive system. Against its defects, a dynamic compensation strategy is implemented in this paper, it compensates for the phase and amplitude error with the PI regulator constructed by the difference of the d-q axis voltage between the delayed state and the ideal state. Compared with the traditional method, this dynamic strategy has a simpler calculation and greatly improves the stability of the high-speed PMSM sensor-less drive system. Finally, the compensation method proposed in this paper is successfully verified by the experiment results.

Multi-loop control of a boost converter needs a current-sensing circuit to detect the inductor current. Current sensorless multi-loop control reduces the cost, size and weight of the converter. The Luenberger observer (LO) is widely used to estimate the inductor current for current sensorless control of a switching converter. However, the design of the LO-based sensorless multiloop control has not been well presented, so far. In this paper, a closed-loop characteristics evaluation method is proposed to design an LO-based current sensorless multi-loop control for boost converters. Simulations show evaluations of the closed-loop characteristics. Practical experiments on a digital processor confirm the simulations.

In this paper, an ANN (artificial neural network) control system is applied to a novel solar-powered active LTD (low temperature differential) Stirling pump. First, a mathematical description of the proposed Stirling pump is presented. Then, optimum operating frequencies of the converter corresponding to different operating conditions ( i.e. different sink and source temperatures and water heads) are investigated using the proposed mathematical framework. It is found that the proposed complex mathematical scheme has a very slow convergence and thus, is not appropriate for real-time implementation of the model-based controller. Consequently, a NN (neural network) model with a lower complexity is proposed to learn the simulation data obtained from the mathematical model. The designed neural network controller is thus applied to a digital processor to effectively tune the converter frequency so that a maximum output power is acquired. Finally, the performance of the proposed mechatronic system is evaluated experimentally. The experimental results clearly demonstrate the feasibility of pumping water at low temperature difference under variable operating conditions using the proposed intelligent Stirling converter.

On the basis of a brief introduction of how the automatic gain control (AGC) of the digital reconnaissance receiver works,this article proposed a digital AGC design method based on the digital processor parts, which provide a guarantee for the digital reconnaissance receiver to work in the complex external electromagnetic signal environment. The engineering implementation of AGC is introduced with specific projects. Both simulation and engineering practice verify the feasibility of this program.

The implementation of a reaction-diffusion (RD) cellular automata (CA) model on an FPGA is presented. The model generates Turing-like patterns, e.g., striped and spotted patterns observed in marking patterns over animal skins, human fingerprints, etc. Moreover, this model has simple dynamics and generates striped or spotted patterns at its equilibrium that is reached within few cycles, which implies that the model is suitable for hardware implementation. To this aim, a digital processor architecture based on the RDCA model is proposed. Finally, the self-organized patterns generated on the FPGA by the implemented processor are presented.

Imaging and Image sensors is a field that is continuously evolving. There are new products coming into the market every day. Some of these have very severe Size, Weight and Power constraints whereas other devices have to handle very high computational loads. Some require both these conditions to be met simultaneously. Current imaging architectures and digital image processing solutions will not be able to meet these ever increasing demands. There is a need to develop novel imaging architectures and image processing solutions to address these requirements. In this work we propose analog signal processing as a solution to this problem. The analog processor is not suggested as a replacement to a digital processor but it will be used as an augmentation device which works in parallel with the digital processor, making the system faster and more efficient. In order to show the merits of analog processing two stereo correspondence algorithms are implemented. We propose novel modifications to the algorithms and new imaging architectures which, significantly reduces the computation time., appears in Signal & Image Processing : An International Journal (SIPIJ) Vol.5, No.6, December 2014. arXiv admin note: substantial text overlap with arXiv:1411.3929

Software defined radar (SDR) is a multi-purpose radar system where most of the hardware processing is performed by software. This paper introduces a concept and technology trends of software defined radar, and addresses the advantages and limitations of the current SDR radar systems. For the advanced SDR concept, the KAU SDR Model (KSM) is presented for the multimode and multiband radar system operating in S-, X-, and K-bands. This SDR consists of a replaceable multiband antenna and RF hardware, common digital processor module with multimode, and open software platform based on MATLAB and Lab VIEW. The new concept of the SDR radar can be useful in various applications of the education, traffic monitoring and safety, security, and surveillance depending on the various radar environments.

This paper investigates the problem of global asymptotic stability of fixed-point state-space two-dimensional (2-D) digital filters described by the Roesser model in the presence of finite wordlength nonlinearities. The class of nonlinearities under consideration captures the combined effects of quantization (except value truncation) and overflow arithmetic employed in practice. A new criterion for the limit cycle-free realization of 2-D digital filters is proposed. The criterion is based on a more precise sector-based characterization of the nonlinearities which exploits the information of the wordlength available in the digital processor. The criterion is compared with the previously reported criteria.

An easy-to-synthesize Schiff base as a selective and colorimetric fluoride sensor via modulation of intramolecular charge transfer (ICT) has been demonstrated. A typical dual-ion binding property along with its distinct reversibility has been explored for YES, NOR and INH logic functions and a potential "Write-Read-Erase-Read" mimic.

An approach to computing that is fast, low-power and precise can be created by combining an analogue in-memory processor with a conventional digital processor.

Radiological methods of examination in diagnosis of pathological conditions and diseases of urinary system are numerous and various, reliable and dominant. They became indispensable and without competition, among other diagnostic methods, using the digital techniques. The aim of this paper was to present the radiological image of pathological conditions and diseases of urinary system diagnosed by intravenous urography using digital techniques and to show the diagnostic possibilities and importance of digital techniques in diagnostic radiology. The paper analyzes pathological conditions and diseases of the kidney in a series of 3100 intravenous urographies (IVU) performed at the Radiology Center, Clinical Center Nis, during the period 2009-2012. Radiographic examination was performed on X-ray device with a TV chain Schimadzu. IVU was performed according to the standard protocol. Contrast media: Ultravist 370 ® . X-ray images were digitally processed in Agfa CR-30 digital processor. The results are shown illustratively, by urographic images - anomalies, calculosis, hydronephrosis, tumors and other pathological conditions and diseases of the urinary system. This paper presents numerous and various pathological conditions and diseases of the urinary system. Among the valuable radiological examination methods IVU has maintained a leading position. The usage of digital techniques made IVU faster, easy and efficient method of examination, while the obtained urograms are of satisfactory quality and adequate contrast visualization of the urinary system. Acta Medica Medianae 2013;52(3):35-41.

Different kinds of algorithms can be chosen so as to compute elementary functions. Among all of them, it is worthwhile mentioning the shift-and-add algorithms due to the fact that they have been specifically designed to be very simple and to save computer resources. In fact, almost the only operations usually involved with these methods are additions and shifts, which can be easily and efficiently performed by a digital processor. Shift-and-add algorithms allow fairly good precision with low cost iterations. The most famous algorithm belonging to this type is CORDIC. CORDIC has the capability of approximating a wide variety of functions with only the help of a slight change in their iterations. In this paper, we will analyze the requirements of some engineering and industrial problems in terms of type of operands and functions to approximate. Then, we will propose the application of shift-and-add algorithms based on CORDIC to these problems. We will make a comparison between the different methods applied in terms of the precision of the results and the number of iterations required. This research was supported by the Conselleria de Educacion of the Valencia Region Government under grant number GV/2011/043.

Where errors, malfunctions or failures in digital systems could increase safety risks, Functional Safety standards and/or Product Liability laws/regulations might not be complied with. Electromagnetic (EM) disturbances can cause interference (EMI) with all digital processors, so must be taken into account for Functional Safety and/or Product Liability. However, it is impossible to do enough EM immunity testing to prove that a digital processor or its software programming is functionally safe enough, and this paper describes the IET's recent guidance on how to deal with this problem.

This chapter introduces the subject of intelligent devices, which are distinguished from their nonintelligent counterparts by their computational processing capability. Discussion starts with a brief review of the main principles of digital computation and how the computation element in an intelligent device interfaces to other measurement system components. It is noted that intelligent devices have a number of names including intelligent instrument, intelligent sensor, smart sensor, and smart transmitter, but, since there are no universal definitions of these terms, devices with similar attributes but from different manufacturers may have different names. This chapter summarizes the common features of intelligent devices and explains the significant advantages that they have compared with nonintelligent devices, particularly in respect to improved measurement accuracy and their ability to perform functions like remote self-calibration and self-diagnosis of faults. This is followed by a discussion of the issues surrounding the communication between intelligent devices and other elements in a measurement/process control system, with coverage of local area networks and digital fieldbuses.

The conventional multi-loop control of a boost converter needs a current sampling circuit to detect the inductor current. Sensorless multi-loop control reduces the cost, size and weight of the power conversion system. The Luenberger observer (LO) is widely used to estimate the inductor current for the sensorless control of a switching converter. However, the design of the LO based sensorless multi-loop control has not been well presented by far. In this paper, a closed-loop characteristics evaluation method is proposed to design a LO based sensorless multi-loop control for boost converters. Simulations show the closed-loop characteristics evaluations. Practical experiments on a digital processor confirm the simulations.

This paper presents a multichannel stimulator ASIC for an implantable vestibular prosthesis. The system features versatile stimulation management which allows fine setting of the parameters for biphasic stimulation pulses. To address the problem of charge imbalance due to rounding errors, the digital processor can calculate and provide accurate charge correction. A technique to reduce the data rate to the stimulator is described. The stimulator ASIC was implemented in 0.6-μ m high-voltage CMOS technology occupying an area of 2.27 mm(2). The measured performance of the ASIC has been verified using vestibular electrodes in saline.

We introduce an idea of synthesizing a class of genetic registers based on the existing sequential biological circuits, which are composed of fundamental biological gates. In the renowned literature, biological gates and genetic oscillator have been unveiled and experimentally realized in recent years. These biological circuits have formed a basis for realizing a primitive biocomputer. In the traditional computer architecture, there is an intermediate load-store section, i.e. a register, which serves as a part of the digital processor. With which, the processor can load data from a larger memory into it and proceed to conduct necessary arithmetic or logic operations. Then, manipulated data are stored back to the memory by instruction via the register. We propose here a class of bio-registers for the biocomputer. Four types of register structures are presented. In silicon experiments illustrate results of the proposed design.

The origin of this article coincides with two different but parallel events. The first is my recent rereading of Gilles Deleuze and Felix Guattari’s book Anti-Oedipus. Capitalism and Schizophrenia (2000), followed by my reflection on the possibility (or necessity) of adopting and adapting some of its key concepts into our time. In his Preface to the Anti-Oedipus, Michel Foucault explained how, in the particular climate of the 1970s, being anti-oedipal was a truly revolutionary lifestyle, a way of living and thinking in constant opposition to all hierarchies and fascisms (including, among the latter, the rigidity of the psychoanalytical and Marxist schools of thought, and all those petty micro-fascisms ‘that constitute the tyrannical bitterness’ of modern daily life) (Foucault in Deleuze and Guattari 2000, XIII). This lifestyle was described by Deleuze and Guattari themselves as ‘schizophrenia’, a horizontal relational attitude that induced one to be inspired by a multiplicity of things rather than guided by a unique dominating principle, to become multiplied into a crowd rather than remain the same individual; in other words, to produce a life in collaboration rather than obey the exclusive and solipsistic logic of a dominating ego.