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The purpose of his paper is to study the radar stealth performance of a Y-type quadrotor with coaxial rotors and parallel rotors.

This Y-type quadrotor is designed as an aerodynamic layout with parallel twin rotors at the front and coaxial twin rotors at the rear. The multi-rotor scattering (MRS) method based on multi-rotor dynamic simulation (MRDS) and electromagnetic scattering module (ESM) is presented. MRDS is used to simulate the complex rotation of parallel rotors and coaxial rotors. ESM is used to calculate the instantaneous radar cross-section (RCS) of the quadrotor.

For a single rotor, the minimum period of the RCS curve at a given azimuth is equal to the basic passage time of the blade, where increasing the speed can shorten this minimum period. When the elevation angle increases, the forward RCS fluctuation of the quadrotor increases, while the average RCS decreases. The change of the roll angle will affect both the mean and the maximum difference of the RCS–time curve at the given lateral azimuth. The increase of the pitch angle will enhance the dynamic amplitude of the RCS–time curve under the forward azimuth.

The research in this article can provide reference for the stealth design of the Y-type quadcopter in the future.

The originality is the establishment of the MRS method. This method could provide value for dealing with the electromagnetic scattering problem of coaxial rotors and parallel rotors.

The accelerating process of economic globalization and the increasingly fierce international competition are conducive to the promotion of the construction of the urban regional innovation system. Based on this, the Bayesian discriminant model was established in this paper, and the development stage of the regional innovation system was prejudged. Then according to the discriminant analysis, the results of the pre judgment were tested. In addition, based on the innovation system of urban planning and construction, a framework of urban planning analysis based on regional innovation system was put forward, which was used to guide regional planning and implementation, and was applied to the planning of Shanxi science and technology innovation city. It is proved that the fuzzy evaluation system based on Bayes is beneficial to the innovative planning of the new city.

The purpose of this paper is to use artificial intelligence to evaluate the risks of urban power network planning.

A fuzzy Bayesian least squares support vector machine (LS_SVM) model is established in this paper, which can learn the risk information of urban power network planning through artificial intelligence and acquire expert knowledge for its risk evaluation. With the advantage of possessing learning analog simulation precision and speed, the proposed model can be effectively applied in conducting a risk evaluation of an urban network planning system. First, fuzzy theory is applied to quantify qualitative risk factors of the planning to determine the fuzzy comprehensive evaluation value of the risk factors. Then, Bayesian evidence framework is utilized in LS_SVM model parameter optimization to automatically adjust the LS_SVM regularization parameters and nuclear parameters to obtain the best parameter values. Based on this, a risk comprehensive evaluation of urban network planning based on artificial intelligence is established.

The fuzzy Bayesian LS_SVM model established in this paper is an effective artificial intelligence method for risk comprehensive evaluation in urban network planning through empirical study.

The paper breaks new ground in using artificial intelligence to evaluate urban power network planning risks.

Now in its seventh major version, the Inmagic database, retrieval and application development software provides a continuously improved system for the library, information centre or any organisation requiring a powerful, variable length field and record database system with powerful Boolean search and complex report generation facilities. The Companion package, Biblio, features predefined database definitions and reports applicable to the library automation situation as well as an excellent tutorial and learning package for any user of the Inmagic software.

In the last few years many new types of light‐guiding optical film structures have been developed. Several applications have been published in the field of optical and optoelectronic integrated circuits, sensor‐elements, etc. The basic component of these systems is the optical waveguide which can be realised with optical fibres or fabricated as a layer structure from different dielectrics and many kinds of glasses. The purpose of this paper is to describe some problems and solutions of optical waveguide thick film manufacturing and also connecting techniques with optical fibres.

THE Nineteenth Salon International de l'Aeronautiquc was principally a British and French affair, although there were notable contributions also from the Netherlands, Italy and the U.S.A. As an exhibition, however, it was patchy and many of the exhibitors showed nothing new; some because of security restrictions, but others undoubtedly because they simply had nothing new to show after two years. The restrictions and economics of today were very much in evidence, and it was even surprising how some of the manufacturers have managed to exist at all since the end of the War.

AT the outset we ought to say that we could probably have done more justice to a paper on the “High Output cf Aero‐Engines.”

The purpose of this paper is to describe the origins of today's new office concepts, focusing on the emergence of mobile and flexible working practices in the 1960s and 1970s. Thereby it intends to add a sense of historical awareness to the ongoing debate about the work environment.

The historical description is based on literature study, looking at research reports, design handbooks and depictions of office life in popular culture such as movies and advertisements.

The paper demonstrates that today's “new ways of working” are by no means new. It shows that the concepts of mobile offices, paperless offices, videoconferencing and flexible workplaces all originate from the end of the 1960s and the early 1970s. It also shows that these concepts were far from mainstream, standing in stark contrast to the rigidity and conservatism of everyday office life at the time.

This paper is the first result of a larger historical analysis of the recent history of the work environment. Further historical research will add to the presented insight in the evolution of office concepts.

The paper's insight into the historical development of office concepts can help workplace strategists to make better, more careful forecasts of future workplace trends.

Whereas most literature on the office concept tends to look at novel ideas and future developments, this paper looks back at the recent past. It discusses early workplace experiments that have been largely ignored, or remained unidentified, in much of the discourse on new ways of working.

Online shopping cart abandonment presents a major problem for online fashion apparel retailers today. This exploratory research aims to validate scales that measure antecedents of online shopping cart abandonment (OSCA) and examine how these reasons contribute to OSCA behaviour. The findings indicated that the eight different reasons (financial reasons, organisational tool, time pressure, intangibility, privacy issues, aesthetic design, social influences and entertainment factors) that drive OSCA are distinct and account for unique variance in the model, validating the measures. Also, the findings revealed that financial reasons and using the cart as an organisational tool are the top two reasons why consumers abandon their carts. This study provides researchers with a better theoretical understanding of the reasons why consumers abandon their online shopping carts. It validates the various reasons why consumers abandon their shopping carts and provides valuable managerial insights on how online marketers may enhance the translation of online browsing behaviour into actual purchases.

A striking feature of Jaques' work is his “no nonsense” attitude to the “manager‐subordinate” relationship. His blunt account of the origins of this relationship seems at first sight to place him in the legalistic “principles of management” camp rather than in the ranks of the subtler “people centred” schools. We shall see before long how misleading such first impressions can be, for Jaques is not making simplistic assumptions about the human psyche. But he certainly sees no point in agonising over the mechanism of association which brings organisations and work‐groups into being when the facts of life are perfectly straightforward and there is no need to be squeamish about them.