Experience with an On‐board Weighing System Solution for Heavy Vehicles

Mining, construction, and other special vehicles for heavy use are designed to work under high‐performance and off‐road working conditions. The driving and executive mechanisms of the support structures and superstructures of these vehicles frequently operate under high loads. Such high loads place the equipment under constant risk of an accident and can jeopardize the dynamic stability of the machinery. An experimental investigation was conducted on a refuse collection vehicle. The aim of this research was to determine the working conditions of a real vehicle: the kinematics of the waste container, that is, a hydraulic rotate drum for waste collection; the dynamics of the load manipulator (superstructure); the vibrations of the vehicle mass; and the strain (stress) of the elements responsible for the supporting structure. For an examination of the force (weight) on the rear axle of a heavy vehicle, caused by its own weight and additional load, a universal measurement system is proposed. As a result of this investigation, we propose an alternative system for continuous vehicle weighing during waste collection while in motion, that is, an on‐board weighing system, and provide suggestions for measuring equipment designs.     

RMS Detector of Multiharmonic Signals

This paper presents a new realization of the implicit root‐mean‐square (RMS) detector, employing three second‐generation current conveyors and MOS transistors. The proposed circuit can be applied in measuring the RMS value of complex, periodic signals, represented in the form of the Fourier series. To verify the theoretical analysis, circuit Simulation Program with Integrated Circuit Emphasis simulations and experiment results are included, showing agreement with the theory.     

Review of objective video quality metrics and performance comparison using different databases

The use of video-based applications has increased in recent years owing to the development of video technology as well as the widespread use of the Internet. Thus the evaluation of perceptual video quality has become very important and numerous video quality assessment (VQA) metrics have been developed over the past years. In this paper, we give a classification and a short review of objective VQA metrics, with a focus on the full reference metrics. With the aim of conducting a reliable test of the VQA metrics performances, we made two databases, each of them including 90 distorted video sequences. We carried out a subjective quality evaluation on these databases and the data were made available to the research community. Furthermore, we compared the performance of nine different, freely available, objective VQA metrics by using three different databases in different resolutions: LIVE Video Quality Database (768×432 resolution) and our two newly created databases for progressively scanned videos, i.e. ETFOS CIF Video Quality (ECVQ) database and ETFOS VGA Video Quality (EVVQ) database. Five different distortion types were used and the total number of 330 video sequences was evaluated. A comparison of metrics was done with respect to accuracy, monotonicity, stability, as well as complexity vs. accuracy criteria. The results show that the resolution, the content of the sequence and the distortion type have a significant influence on the performances of VQA metrics. Metrics that generally achieve a high correlation with subjective results for all databases and all distortion types are MOtion-based Video Integrity Evaluation (MOVIE) and Foveated Mean Squared Error (FMSE), but MOVIE has significantly higher complexity than FMSE. An exception is the distortion caused by IP transmission for which none of the analyzed metrics has shown satisfying accuracy and stability.     

Rigorous analysis on performance of LEO satellite ground station in urban environment

Microsatellites in low Earth orbits (LEOs) have been in use for the past two decades. LEO satellites are used for public communication and also for scientific purposes, and the orbits vary with the type of satellites and the primary purposes. LEO scientific satellites have a variety of applications, including Earth surveillance and astronomy applications. These satellites provide opportunities for investigations for which alternative techniques are either difficult or impossible to apply. Thus, it may be expected that such missions will be further developed in the near future especially in fields where similar experiments by purely Earth‐based means are impracticable. Ground stations have to be established in order to communicate with such satellites, and the quality of communication depends on the performance of the satellite ground station, in addition to that of the satellite. Before the implementation of the ground station, analyses related to environmental factors have to be considered, especially in urban areas. Rain effects, the impact of intermodulation products, and contact time duration at low elevation angles are some of the aspects that are considered in this work and which influence the final decisions on the design of the ground station. Measurements on the ground station based on Sun flux density are described, which provide an opportunity to check the performance of the ground station. Copyright © 2007 John Wiley & Sons, Ltd.     

Innovating and management of the knowledge base on the example of IT applications

This paper presents ongoing research in standardised subfields of information technology (IT). This is an isolated segment of a comparative statistical analysis of trends in global (ISO) and local (SRPS) standardisation of knowledge sources (KS) in the subfields of IT applications (ICS2?=?35.240). The ultimate goal of the study is to define management of knowledge base systems. The specific objectives of this research are related to the presentation of original results, comparative criteria, and defining the level of innovativeness (based clustering) in forming a knowledge base (KB), from the knowledge source to modelling, implementing and improving the knowledge base system on the example of the subfields of IT applications.     

Frequency and time domain comparison of selective polynomial filters with corrected phase characteristics

Two solutions to the polynomial filter’s transfer function synthesis problem are considered for comparison in the frequency and time domain: the broad class of filters with a critical monotonic amplitude characteristic (CMAC) in the passband and filters which use Chebyshev (C) polynomials. To complete the synthesis procedure for linear phase applications, group delay correctors are considered, for which a convenient approximation procedure is proposed here. Comparisons of the original functions and the corrected ones are performed in the frequency and time domain. It is shown that when CMAC and C are compared as such, the latter is by no means preferable from the selectivity point of view, while the opposite stands when the comparison is based on passband amplitude distortions. When phase-corrected filtering functions are compared, based on circuit complexity and time domain performance, the CMAC are shown to be preferable.     

Multifractal analysis of human retinal vessels

In this paper, it is shown that vascular structures of the human retina represent geometrical multifractals, characterized by a hierarchy of exponents rather then a single fractal dimension. A number of retinal images from the STARE database are analyzed, corresponding to both normal and pathological states of the retina. In all studied cases, a clearly multifractal behavior is observed, where capacity dimension is always found to be larger then the information dimension, which is in turn always larger then the correlation dimension, all the three being significantly lower then the diffusion limited aggregation (DLA) fractal dimension. We also observe a tendency of images corresponding to the pathological states of the retina to have lower generalized dimensions and a shifted spectrum range, in comparison with the normal cases.     

Subtractive contact-patterning of molecular organic films

An array of optoelectronic applications requires micro- and nanoscale patterning of molecular organic films. A subtractive patterning technique is developed to define micron-sized features of nanometer range thickness on a variety of hole transporting and hole blocking materials. Lateral resolution of patterned features is controlled by micron-scale stamp shapes, while the removal of the patterned nanoscale film thicknesses (sub-10 nm to over 40 nm) is correlated to strength of interfacial and intermolecular forces. Using this process, a multi-color organic light-emitting device is fabricated, demonstrating the ability of contact patterning to manipulate organic molecular films on the micro- and nanoscales.     

GigaManP2P: an overlay network for distributed QoS management and resilient routing

Management of long‐distance, high‐speed optical backbones spanning multiple administrative domains requires new solutions for challenging tasks. In particular, it is not trivial to negotiate, monitor and continuously enforce the required quality of service (QoS) for applications that span multiple domains. This paper proposes GigaManP2P: a novel peer‐to‐peer (P2P) management architecture for high‐speed QoS‐aware backbones. GigaManP2P peers provide management services in a ubiquitous fashion through modules that interface with both the communication infrastructure and network users. In particular, we describe management services for on inter‐domain QoS monitoring and resilient routing. After detecting a QoS constraint violation trend, a proactive rerouting strategy is triggered based on redundant virtual circuits, allowing both full and partial rerouting. The P2P overlay implementation is the basis for allowing transparent communication across autonomous systems. Experimental results showing the overhead of the P2P infrastructure in comparison to raw Simple Network Management Protocol, and the performance of the rerouting strategy, are presented. Copyright © 2011 John Wiley & Sons, Ltd.     

Studies on robust control of parallel operating dc/dc converters

Contents In this paper, an optimal robust control approach for parallel operating dc/dc converters is presented. Various types of controllers using frequency domain optimization method based on -optimality framework are designed. Different structures of low-order controllers, decentralized controller and a new controller based on Internal Model Control (IMC) theory are developed to improve the robust performance of parallel operating dc/dc converters against uncertainties and disturbances. The proposed controllers are robust for setpoints and/or for disturbances. Finally, a comparison between the performance of the closed-loop system with designed robust decentralized and IMC controllers is obtained.

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Untersuchung verschiedener robuster Regelungsstrukturen für parallele Gleichstromwandler

Übersicht Im Mittelpunkt des Beitrages steht die vergleichende Untersuchung verchiedener robuster Mehrgrößen-regelungsstrukturen für parallele Gleichstromwandler. Der Entwurf der Regler erfolgt im Frequenzbereich und nutzt das -Analyse- und Synthesekonzept. Es werden verschiedene Reglertypen niedriger Ordnung, dezentrale Regler und ein neuer IMC (Internal Model Control) Regler betrachtet. Ziel ist es, die Robustheit der Regelgüte bezüglich Modellungenauigkeiten und Störeinflüssen bei parallelen Gleichstromwandlern zu verbessern. Die vorgeschlagenen Regler zeigen robustes Führungs- und/oder Störverhalten. Abschließend erfolgt ein Vergleich der Regelgüte, die entworfenen robusten dezentralen und IMC-Regler im geschlossenen Kreis erreichen.