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In order for a closed-loop radar system to adapt properly to changing operational conditions, the performance standards and requirements of the radar system must be known. Often, these performance standards are contained in statements made in language, which describe the different goals of the radar system. In this article, we explore the use of language-based cost functions (LBCFs) to encode performance standards made in imprecise language into an objective function, which a fully adaptive radar (FAR) can use to optimize its performance in real time. To enable the LBCFs, we also propose a statement decomposer, which takes in statements as inputs and yields the information required by LBCFs as outputs. A simulation study of a FAR tracking a running human is conducted with four different cost function methodologies: quadratic, weighted global criterion, fuzzy optimization, and LBCFs. Results show that when statements are properly formulated and presented, the statement decomposer is able to successfully extract the relevant information. Results also show that when paired with a previously developed optimization routine, the LBCF system is capable of autonomously creating cost functions that outperform the other cost functions in the simulated FAR target tracking scenario. [ABSTRACT FROM AUTHOR]

This article presents a comparison of measurement methods for current and voltage distortions in low-voltage networks in the frequency range from 2 to 150 kHz (supraharmonics). The comparison encompasses the methods informatively described in IEC and CISPR international standards, as well as other innovative techniques presented in the literature. This work is carried out within a novel framework that includes advanced and complex synthetic test signals, as well as real grid recordings that allow an accurate comparison of the performance of the tested methods. Specifically designed indices are employed to characterize the accuracy of the tested methods in the frequency and amplitude assessments. In light of that, the strengths and weaknesses of the methods are identified. The results of this article contribute to the ongoing standardization work carried out by the IEC SC77A/WG9 with the purpose of defining a normative measurement method suitable for assessing grid disturbance levels in the range from 2 to 150 kHz. [ABSTRACT FROM AUTHOR]

Our impression about one person often updates after we see more aspects of him/her and this process keeps iterating given more meetings. We formulate such an intuition into the problem of person re-identification (re-ID), where the representation of a query (probe) image is iteratively updated with new information from the candidates in the gallery. Specifically, we propose a simple attentional aggregation formulation to instantiate this idea and showcase that such a pipeline achieves competitive performance on standard benchmarks including CUHK03, Market-1501 and DukeMTMC. Not only does such a simple method improve the performance of the baseline models, it also achieves comparable performance with latest advanced re-ranking methods. Another advantage of this proposal is its flexibility to incorporate different representations and similarity metrics. By utilizing stronger representations and metrics, we further demonstrate state-of-the-art person re-ID performance, which also validates the general applicability of the proposed method. [ABSTRACT FROM AUTHOR]

With the increasing popularity of mobile phones and tablets, the explosive growth of query-by-capture applications calls for a compact representation of the query image feature. Compact descriptors for visual search (CDVS) is a recently released standard from the ISO/IEC moving pictures experts group, which achieves state-of-the-art performance in the context of image retrieval applications. However, they did not consider the matching characteristics in local space in a large-scale database, which might deteriorate the performance. In this paper, we propose a more compact representation with scale invariant feature transform (SIFT) descriptors for the visual query based on Grassmann manifold. Due to the drastic variations in image content, it is not sufficient to capture all the information using a single transform. To achieve more efficient representations, a SIFT manifold partition tree (SMPT) is initially constructed to divide the large dataset into small groups at multiple scales, which aims at capturing more discriminative information. Grassmann manifold is then applied to prune the SMPT and search for the most distinctive transforms. The experimental results demonstrate that the proposed framework achieves state-of-the-art performance on the standard benchmark CDVS dataset. [ABSTRACT FROM AUTHOR]

The primary objective of many antenna measurement facilities is to provide a specified high accuracy of the measured data. The validation of an antenna measurement facility is the process of proving that such a specified accuracy can be achieved. Since this constitutes a very challenging task, antenna measurement accuracy has been the subject of much research over many years and a range of useful measures have been introduced. Facility comparisons, together with antenna standards, error budgets, facility accreditations, and measurement procedure standards, constitute an effective measure towards facility validations. This paper documents the results of a comparison between 8 European antenna measurement facilities with a specially designed reference antenna, the DTU-ESA 12 GHz Validation Standard Antenna (VAST-12). The electrical and mechanical properties of the VAST-12 antenna are presented and its three different coordinate systems are defined. The primary objective of the comparison is to obtain experience and results that can serve to develop standards for validation of antenna measurement facilities. The paper focuses on the comparison of the radiation pattern and presents not only the measurement data obtained at the facilities, but also investigates several procedures for comparing these data. This includes various definitions of pattern difference and statistical measures as well as a reference pattern. The comparison took place in 2004-2005 as part of the European Union network of excellence called ACE-Antenna Centre of Excellence. [ABSTRACT FROM AUTHOR]

This paper describes the significant enhancements brought to an original methodology designed for testing measurement software. In a previous paper, the authors proposed a black- box seven-step procedure that allows the functional verification of complex instrument software to be performed. The main features of the procedure are concerned with the following: 1) the ability of reproducing actual correlations among the software inputs and 2) the need for a limited number of test cases. Making use of innovative statistical techniques, the methodology performance and reliability have been enhanced. Two further steps have been added with the aim of improving the correlation coefficient assessments and providing the estimations with a confidence level. Finally, a new strategy has been studied to optimize the number of test cases. The effects of the new solutions on the performance of the methodology are evaluated by applying the procedure to a complex software module employed in an automotive system. A comparison with the previous methodology version is also reported. [ABSTRACT FROM AUTHOR]