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Despite the wide dissemination and application of current signature analysis (CSA) in general industry, CSA is not commonly used in the wind industry, where the use of vibration signals predominates. Therefore, the purpose of this paper is to review the use of generator CSA (GCSA) in the online fault detection and diagnosis of wind turbines (WTs).

This is a bibliographical investigation in which the use of GCSA for the maintenance of WTs is analyzed. A section is dedicated to each of the main components, including the theoretical foundations on which GCSA is based and the methodology, mathematical models and signal processing techniques used by the proposals that exist on this topic.

The lack of appropriate technology and mathematical models, as well as the difficulty involved in performing actual studies in the field and the lack of research projects, has prevented the expansion of the use of GCSA for fault detection of other WT components. This research area has yet to be explored, and the existing investigations mainly focus on the gearbox and the doubly fed induction generator; however, modern signal treatment and artificial intelligence techniques could offer new opportunities in this field.

Although literature on the use of GCSA for the detection and diagnosis of faults in WTs has been published, these papers address specific applications for each of the WT components, especially gearboxes and generators. For this reason, the main contribution of this study is providing a comprehensive vision for the use of GCSA in the maintenance of WTs.

The purpose of this paper is to directly link information technology (IT) education with real-world phenomena.

The selected objectives are achieved by modeling line of sight (LOS) and nonline of sight (NLOS) mobile channels using corresponding distributions. Within the described experiments, students verify whether modeled generators generate random variables accordingly to the selected distribution. The results of observations are directly compared with theoretical expectations. The methodology was evaluated by students via questionnaires.

The results show that the proposed methodology can help graduate or undergraduate students better comprehend lectured material from mobile communications or mathematical statistics.

The hands on experience using the EMONA system make the approach original.

ADVANCED GENERATOR TECHNOLOGICAL CONCEPTS by the Westinghouse Aerospace electrical division in joint development with Sundstrand Aviation offer dramatic improvements in electrical power system weight and reliability.

This paper proposes a design of an efficient and automated experimental platform for frequency modulated continuous wave (FMCW) radars. The platform can quickly flexibly generate the waveform that meets measurement requirements and significantly improve experimental efficiency.

This platform not only includes radio frequency devices but also integrates a programmable transmitter based on field programmable gate array. By configuring the waveform data, the experimental platform can generate waveforms with adjustable parameters and realize automatic emission, reception and processing of signals. Different from traditional fast Fourier transform, this paper uses a discrete-time Fourier transform to process low-frequency signals to get more accurate results.

The authors demonstrate the effectiveness of the platform through a single-path cable experiment, an indoor ranging experiment by using different modulating waveforms and a speed measurement experiment. With complete functions and strong flexibility, the platform can operate effectively in various conditions and greatly improve the efficiency of research and study.

The platform can accelerate the research studies and applications of FMCW radars in the fields of automatic drive, through-wall detection and health-care applications.

Cost and functionality are taken into account in the platform, which can significantly improve the efficiency of research. The proposed signal processing method improves the accuracy while its computation complexity does not increase significantly.

The paper aims to achieve translational shaking tests on a 6-DOF hydraulic parallel manipulator. Shaking tests are commonly performed on shaking tables, which are generally used for small motion ranges and are usually financially costly. The research is required to generate shaking motions in three translational directions for a specimen for shaking tests, but it also needs to produce 6-degree of freedom (DOF) motions with large motion ranges.

A hydraulic 6-DOF (degree of freedom) parallel manipulator is applied to achieve this goal. The link-space control is adopted for the manipulator, and PID controller and feed-forward controller are used for each loop of the system. A hybrid reference signal generator is proposed by using a shaking controller, which is developed to convert the shaking motion into position signal. The converted result is directly added to the pose signal. The whole real-time control system is realized by using MATLAB xPC Target.

The developed method is verified on the hydraulic 6-DOF parallel manipulator with specimen. Experiments show very promising results that the proposed technology is really applicable to perform translational shaking tests on the hydraulic parallel manipulator.

A simple yet efficient solution is proposed that allows shaking tests in three translational directions performed on the hydraulic 6-DOF parallel manipulator with wide motion ranges. The paper presents a state-of-the-art related to the applications of parallel robots in several fields of technology.

THE electrical supply system is designed to provide both 200 volt a.c. and 28 volt d.c. services for operation of the aircraft. Although electrical power is required for the operation of the auto‐stabiliser system, this is not essential for flight and the flying controls are non‐electric. The aircraft does not therefore, depend on the integrity of the electrical system for flight. Loads, such as undercarriage lowering selection etc., required to operate if a total generation failure has occurred, are all d.c. and are fed by the main aircraft batteries. As a further precaution basic flight and communication facilities can also be powered in an emergency from a standby battery which is not charged in flight and is therefore independent of any of the normal aircraft services.

The purpose of this paper is to simulate micro direct methanol fuel cells (DMFCs) for portable electronic devices by means of a non‐linear equivalent circuit based on a fully coupled, dynamic, electrochemical model.

The equivalent circuit accounts for electrochemical reactions and electric current generation inside the catalyst layers, electronic and protonic conduction, fuel crossover across the membrane, mass transport of reactants inside the diffusion layers. The V‐I characteristic of the device is obtained by combining mass transport and electric equations. The transient dynamics is accounted for by an equivalent capacitance, while the slow dynamics by the mass conservation equation. The equivalent circuit is embedded in the Matlab/Simulink^® dynamic model of a hybrid system, consisting of a micro fuel cell and a Li‐ion rechargeable battery.

An original equivalent circuit of a passive DMFC suitable for static and dynamic simulations under variable loading conditions is proposed and validated.

The one‐dimensional model of the micro cell does not take into account transverse mass transfer and current density variations in the cell layers, which can be due to non‐homogeneous materials or to the complex dynamics of the convective mass flow in the reservoir and in the room air.

The equivalent circuit can be used for simulating the dynamic performance in realistic operating conditions when the fuel cell is used to supply the electronic equipment through a power management unit.

The DMFC is described from an electrical point of view as a controlled non‐linear generator; such equivalent representation is particularly suited for designing power management units for electronic portable devices.

The purpose of this paper is to solve the problem of weak low-frequency vibration measurement capability of FBG accelerometer, and propose a FBG accelerometer based on cross reed.

This study proposed a new type FBG acceleration sensor based on cross reeds. When the sensor vibrates, the mass block in the new structure rotates around the center of the cross reeds, which could eliminate the impact of friction, reduce the natural frequency of the sensor and improve its sensitivity. This study theoretically analyzed the impact of several structural parameters on the sensitivity and natural frequency of the proposed sensor and used COMSOL to perform static stress analysis and modal simulation; in this study, a test system was built to test the performance of the proposed sensor.

The test results revealed that the proposed sensor had a natural frequency of 94 Hz; within a low-frequency range of 1–65 Hz, its sensitivity response was flat, the dynamic range was 81.89 dB, the sensitivity was 243.59 pm/g and the linearity was 99.97%. The cross reeds effectively strengthened the structural stability, the relative standard deviation of the repeatability of the sensor was 0.89% and the transverse crosstalk in the working frequency band was −26.97 dB.

This study innovatively proposes the structure of the two symmetrical cross reeds, which can improve sensitivity by eliminating the influence of friction, and the structure of cross reeds can effectively suppress the influence of lateral crosstalk. The proposed sensor can realize real-time accurate measurement of low-frequency weak vibration signals.