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The purpose of this paper is to solve the azimuth sensitivity of a high-resolution range profile (HRRP), which is one of the biggest obstacles faced by a radar automatic target recognition (RATR) system.

Aimed at addressing the shortcomings of the equal angular-sector segmentation based on the scatterer model, an adaptive angular-sector segmentation is proposed on the basis of grey incidence analysis (GIA).

The main conclusions reached are as follows. First, the adaptive angular-sector segmentation in terms of GIA is suitable for RATR based on the HRRP; and, second, the adaptive angular-sector segmentation based on the type-B degree of grey incidence model is better than the Deng-Si degree of grey incidence model and the degree of grey slope incidence model.

The outcome obtained in this paper can be selected for the RATR application.

This paper has been built on the basis of previous research achievements, and a new RATR method of adaptive angular-sector segmentation is presented based on the GIA.

For the production of sensor elements, thick film technology can be used. Advantages of this technology such as ease of production, low cost, high reliability and the possibility of integration with front‐end electronic circuits, make the thick film sensor an interesting alternative to existing sensor elements. In this paper two examples of thick film thermal sensors are presented.

Aircraft flight pressurization/depressurization cycling causes the skin to inflate and deflate, stressing it around the rivets that fasten it to the airframe. The resulting strain, exacerbated by corrosion, drives the growth of initially microscopic cracks. To avoid catastrophe, aircraft are inspected periodically for cracks and corrosion. The inspection technology employed is ∼90 percent naked‐eye vision. We have developed and demonstrated robotic deployment of both remote enhanced 3D‐stereoscopic video instrumentation for visual inspection and remote eddy current probes for instrumented inspection. This article describes the aircraft skin inspection application, how robotic deployment may alleviate human performance problems and workplace hazards during inspection, practical robotic deployment systems, their instrumentation packages, and our progress toward developing image enhancement and understanding techniques that could help aircraft inspectors to find cracks, corrosion, and other visually detectable damage.

The purpose of the research has been the primary consideration and evaluation of a cost effective, reliable, robust and simple process of radio frequency identification (RFID)-based stock control, asset management and monitoring of concrete safety bollards used in the road environment. Likewise, the consideration of the use of the same system and technology to other items in and around the general road infrastructure.

The research approach undertaken has been an evaluation of the use of currently available RFID technology, with a key emphasis on low cost, ease of use, reliability and convenience. Practical field exercises completed in considering the relevant RFID tags and readers and associated software and apps and necessary software integration and development have been undertaken. At the same time, evaluating the specific limits created in the specific environment is being applied. Of particular interest has been the use of a moving scan in a vehicle drive-through or pass-bye, type reading system. This has been determined to be viable and completely practical, drastically reducing the key issue of time-taken. Practical application of the system from idea to real life application has been undertaken. The integration of the use of the RFID tag and reader system with necessary and related software to database upload and storage has been established. The creation of an online facility to allow the appropriate use of the data and to include the convenient output of an asset report has been undertaken.

The findings have provided the necessary insight confirming the use of RFID technology as a simple yet reliable, cost effective and adaptable stock control, asset management and geo-locating system in the road environment. The use of such systems in this particular environment is in its infancy, and is perhaps novel and original in the specific aspect of using the system to stock control, manage and monitor road safety concrete bollards and other roadside objects in the road environment.

To establish if in fact, stock control geo-locating can be reliably undertaken with the use of RFID tags and readers in the specific road and road construction environment, particularly with the use of moving RFID reading of passive tags. To establish the minimum requirements of a field usable RFID tag and reader, specifically applicable to the concrete safety bollards, however to other roadside furniture. To identify the minimum requirements of a function, simple app to minimise general requirements of the overall stock control and monitoring of the RFID-tagged objects. To establish the possibility of reading the tag data, global positioning system (GPS) location and video imaging footage as a single operation function. To determine the basic parameters or limits of the GPS geo-locating, on the proposed products selected and overall system. To determine the current best practice in respect of reasonable accuracy and detail in relation to price considerations to a fully function stock control and monitoring system. To identify the minimum requirements of an online database to receive, house and provide ongoing access to and report on the data. To identify the key differences and benefits between traditional stock control and monitoring systems, against that of proposed RFID tag, read and geo-locating system.

The problem of port and starboard ambiguity will exist when only utilize the vector or scalar parameters. Meanwhile, the amplitude-phase error between the vector and scalar can also cause this problem. In this paper, a compound MEMS vector hydrophone which contains cilia vector microstructure and piezoelectric ceramic tube has been presented to solve the problem. Compared with traditional MEMS vector hydrophone, the compound MEMS vector hydrophone can realize the measurement of sound pressure and vibration velocity simultaneously.

A compound MEMS vector hydrophone has been presented. The unipolar directivity of the combined signal which combine the acoustic pressure and vibration velocity is used to achieve the direction of arrival (DOA). This paper introduced the working principle and the target detection mechanism of the compound vector hydrophone. The amplitude and phase error are analyzed and corrected in the standing wave tube. After that, the authors use beam-forming algorithm to estimate the DOA.

The experimental results in the standing wave tube and the external field verified the vector hydrophone's directional accuracy up to 1 and 5 degrees, respectively.

The research of compound vector hydrophone plays an important role in marine acoustic exploration and engineering applications.

This research provides a basis for MEMS hydrophone directivity theory. The compound vector hydrophone has been applied in the underwater location, with a huge market potential in underwater detection systems.

The purpose of this paper is to simulate and analyze the excitation and propagation of surface plasmon polaritons (SPPs) on sinusoidal metallic gratings in conical mounting.

Chandezon's method has been implemented in MATLAB environment in order to compute the optical response of metallic gratings illuminated under azimuthal rotation. The code allows describing the full optical features both in far- and near-field terms, and the performed analyses highlight the fundamental role of incident polarization on SPP excitation in the conical configuration.

Results of far-field polarization conversion and plasmonic near-field computation clearly show that azimuthally rotated metallic gratings can support propagating surface plasmon with generic polarization.

The recent papers experimentally demonstrated the benefits in sensitivity and the polarization phenomenology that are originated by an azimuthal rotation of the grating. In this work, numerical simulations confirm these experimental results and complete the analysis with a study of the excited SPP near-field on the metal surface.

ALL FOUR portable instrument approach and landing aid systems shown at the NATO evaluation competition are of considerable interest and significance.

IN the autumn of 1986, a Plessey Microwave Landing System (MLS) ground station was installed at runway 28R at Heathrow for participation in UK operational trials. At the same time, British Airways began evaluation in a Boeing 757 aircraft of both the system itself and receivers of several manufacturers. The first of these were from the Bendix Corporation and initiated trials which are due to last around 18 months. The MLS system, like ILS, uses ground based transmitters and airborne receivers to determine the aircraft's position in terms of azimuth and elevation angles with respect to the transmitters. The transmissions themselves may carry some or all of the information relating to approach azimuth and elevation angles (analagous to ILS Localiser and Glide Slope, respectively) as well as back azimuth and auxiliary data such as meteorological information. All of these functions operate on the same radio frequency using time division multiplexing whereby time slots for each function follow each other in a sequence. Each function transmission starts with a preamble which tells the receiver which function is being used thus enabling it to select the correct decoding format.

IN the design of the Hawk/Ground Attack/Trainer aircraft, Hawker Siddeley Aviation had two targets in view (a) to produce a versatile, tough aircraft to a fixed price and (b) to produce an aircraft having a very high degree of reliability as a complete weapon system.

THE YG‐1081 COLLISION WARNING SYSTEM (CWS) introduced by Honeywell Inc. operates on a cooperative basis with other aircraft with like equipment. The system is, in effect, a C‐band (5·08 GHz) pulse beacon ranging system. Each CWS serves both on interrogation and response function. There are three modes of operation: the interrogation mode, the response mode, and the system test mode.