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This study aims to provide a new method of multiscale directional Lyapunov exponents (MSDLE) calculated based on the state space reconstruction for the nonstationary time series, which can be applied to detect the small target covered by sea clutter.

Reconstructed state space is divided into non-overlapping submatrices whose columns are equal to a predetermined scale. The authors compute eigenvalues and eigenvectors of the covariance matrix of each submatrix and extract the principal components σ_ip and their corresponding eigenvectors. Then, the angles ψ_ip of eigenvectors between two successive submatrices were calculated. The curves of (σ_ip, ψ_ip) reflect the nonlinear dynamics both in kinetic and directional and form a spectrum with multiscale. The fluctuations of (σ_ip, ψ_ip), which are sensitive to the differences of backscatter between sea wave and target, are taken out as the features for the target detection.

The proposed method can reflect the local dynamics of sea clutter and the small target within sea clutter is easily detected. The test on the ice multiparameter imaging X-ban radar data and the comparison to K distribution based method illustrate the effectiveness of the proposed method.

The detection of a small target in sea clutter is a compelling issue, as the conventional statistical models cannot well describe the sea clutter on a larger timescale, and the methods based on statistics usually require the stationary sea clutter. It has been proven that sea clutter is nonlinear, nonstationary or cyclostationary and chaotic. The new method of MSDLE proposed in the paper can effectively and efficiently detect the small target covered by sea clutter, which can be also introduced and applied to military, aerospace and maritime fields.

The world's first helicopter AEW (Airborne Early Warning) squadron has been formed by the Royal Navy in a commissioning ceremony at RNAS Culdrose, Cornwall, today (November 9).

Incoherent primary radar is an applicable means for security surveillance of low-altitude airspace. An experimental airspace surveillance radar system has been developed for such applications. Target detector based on radar images is a powerful technique for the system. The main difficulty in designing such a detector is the rejection of heavy edge clutter for the plane position indicator (PPI) radar images after background subtraction.

The paper proposes an edge clutter rejection (ECR) detector with spatial characteristics to detect target instead of sheer threshold segmentation.

The paper chooses the optimal parameter values for the ECR detector and compares it with the existing techniques. Detection results show that the proposed detector achieves higher probability of detection with low false alarm rate, outperforming the fixed-threshold detector and the popular constant false alarm rate detectors. The ECR detector also presents limited computational cost due to its concentration on the pixels detected by the fixed-threshold algorithm with low threshold.

The aviation security of low-altitude airspace can be greatly increased by designing affordable airspace surveillance radar system.

The paper presents critical techniques for clutter rejection with PPI images, which is a significant part of the surveillance system.

The purpose of this paper is to study various ship detection methodologies. The accuracy of ship detection using satellite images still suffers from disturbances due to cluttered scenes and varying ship sizes. The suitability of the techniques for various applications is explained in this survey.

A list of data on the subject was gathered and processed into tables. The test outcomes were then discussed to determine the most effective ship detection technique under various complex environments.

In this work, the advantages and disadvantages of different classification techniques of ship detection are highlighted. The suitability of the techniques for various applications is also explained in this survey. Several hybrid approaches can be developed in order to increase the accuracy of ship detection system. This survey also aids in highlighting the significant contributions of satellite images to effective ship detection system.

In this paper, studying various ship detection methodologies is given specific attention. A survey on ship detection and recognition is clarified with the detailed comparative analysis of various classifier techniques.

This study surveys professional niche sports sponsors in an effort to empirically understand what selection criteria these companies deem important when evaluating professional niche sports sponsorship proposals. Findings suggest that professional niche sports properties may possess unique attributes on which sponsors place very high levels of importance, such as cost effectiveness, flexibility in assisting sponsors achieve their objectives, a more targeted fan-base and decreased sponsorship clutter. Pragmatically, findings provide professional niche sports managers with tools that may be useful when competing for sponsorship funding against more established mainstream sports properties. Theoretically, the current study begins to fill a gap in the sports sponsorship literature which has primarily focused on mainstream professional sports, major intercollegiate sports and elite amateur sports such as the Olympic Games.

The purpose of this paper is to improve active sonar detection performance in shallow water. A stochastic‐like model multivariate elliptically contoured (MEC) distributions is defined to model reverberation, which helps to reveal structure information of target signatures.

Active sonar systems have been developed with wider transmission bandwidths and larger aperture receiving array, which improve the signal‐to‐noise ratio and reverberation power ratio after matched filtering and beamforming. But, it has changed the statistical distribution of the reverberation‐induced envelope from the traditionally assumed Rayleigh distribution. The MEC is a kind of generalized non‐Gaussian distribution model. The authors theoretically derive the compound Gaussian, Rayleigh‐mixture, Weibull, K distributions are all special cases of MEC. It is known that Weibull and K distributions have obvious heavy‐tail than Rayleigh distribution. MEC is a suitable model to characterize non‐Rayleigh heavy‐tailed distribution of reverberation.

The analysis of test data shows reverberation envelopes obviously deviate Rayleigh distribution. In a broad non‐Gaussian framework, reverberation is modelled as MEC distribution, which is suitable to characterize non‐Rayleigh reverberation. The received data in trials validate the effectiveness of MEC model. The real data envelops follows K distribution, which is a special case of MEC. So, the MEC can be applied to develop novel signal‐processing algorithms that mitigate or account for the effects of the heavy‐tailed reverberation distributions on the target detection.

The limited sea test data are the main limitation to prove model validation in further.

A very useful model for representing reverberation in shallow‐water.

The MECs in fact represent an attractive set data model for adaptive array, and it provides a theoretic framework to design an optimal or sub‐optimal detector.

Metal of the fan‐jet HS 146 will be cut in the New Year and already the full scale mock‐up is complete. Able to operate from 4,000ft strips and with superior climb and terrain clearance capabilities, the aircraft will be rolled out for first flight by the end of 1975.

The key research issue addressed in this paper is whether individuals perceive advertisements featuring themes from their own religion more positively, and advertisements featuring religious themes from other religions less positively, than neutral ads. In the process, this paper aims to test whether the in-group bias theory (IGBT) and the polarized appraisal theory (PAT) apply in a religious context.

Respondents in a large Indian University were shown advertisements featuring Hindu and Muslim themes as well as a neutral advertisement in the context of pet adoption. Cognitive and affective response measures were used for evaluation.

Respondents did not evaluate advertisements with their own religion’s symbols any more positively than neutral advertisements but did evaluate advertisements with themes from other religions more negatively than neutral ads. In sum, religious advertisements did not have any positive effect on in-group respondents, but rather worked in antagonizing out-group respondents.

Both IGBT and PAT did not work as predicted when tested on in-group respondents but worked as expected on out-group respondents.

In the Indian market, using religious themes has largely negative consequences in terms of alienating out-group members, with no commensurate advantage on in-group members. Firms are better off not using religious advertising, and this decision would likely have a positive impact on a firm’s bottom line.

Though, the general topic of religious advertising has been much researched, but this paper deals with the role of religious symbols in advertising in the Indian context, which is done for the first time in a multi-religious context. Further, the applicability of IGBT and PAT is also tested for the first time in religious advertisement context.

Fifty years ago ,on 21st May 1927, Charles Lindbergh landed on this very field, Le Bourget, after having made the first non‐stop Atlantic crossing from New York to Paris. Several days earlier, Nungesser and Coli met their tragic end in attempting the flight from Paris to New York, an exploit that Costes and Bellonte succeeded in making only three years later.

THE Deutsche Luftfahrtschau, or as it is more generally known, the Hanover Air Show, held every two years by the Bundesverband der Deutschen Luft‐ und Raumfahrtindustrie e.V. (Federal Association of the German Air and Spacecraft Industries). This year's Show will be held from April 26 to May 5 at the Hanover Langenhagen Airport and will be held at the same time as the famous Hanover Fair.