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COMPREHENSIVE research on the stress conditions of the airscrew hub, arising from the centrifugal forces which exceed 30 tons on each blade, have led to important advances in design which, with minimum dimensions and weight, allow the installation in the hub of the pitch‐adjusting mechanism. Some examples show how the basic principles of the design originated in complementary experimental and mathematical research; where calculation was abandoned owing to excessive complication in shape, the gap was filled by practical stress measurements, while, on the other hand, it was possible by calculation to extrapolate the results of experimental tests to points which were not accessible for direct measurement.

THE originality of the Escher Wyss airscrew, which has been adopted by the Swiss Air Force, is based on the fact that its conception has, since its inception, taken into account all the requirements of a modern variable pitch airscrew. These conditions may be summarized as follows, that the airscrew must normally ensure automatic control at constant engine speed, adapting itself to every condition of flight, and that it should provide, when required, for operation as an aerodynamic brake, and be capable of being moved to the fully feathered position. The essentially mechanical problems, such as the anchorage of the blades in the hub and the design of the pitch control mechanism, must naturally find correct solutions to ensure reliability, together with that simplicity of control which is an essential property of all modern aircraft components.

SINCE the first successful flight tests were made with the Escher Wyss airscrew some years ago, this type has been distinguished in this sphere by several fundamental innovations . From the beginning a very high speed of adjustment of approximately 8 deg./sec. was attained in normal operation as an automatic, constant‐speed airscrew. This property and the wide range of speed control between 100 per cent and approximately 40 per cent of the rated r.p.m. made it possible completely to release the pilot from control of the airscrew. Thus the problem of the automatic airscrew was finally solved (Fig. 1). That this solution was satisfactory has been proved by many years' service under the most stringent conditions in the Swiss Air Force.

UNTIL 1952 Queen's University was fortunate to have one main library building. With the establishment of the Institute of Clinical Science in the hospital area 1½ miles from the main university site, the formation of a separate medical library near the hospitals was considered essential.

IN the annual reports of many libraries in all parts of the country decreased issues are bewailed. True the decrease, in most cases, does not amount to much; but there it is, and in each annual report it has to be explained. And the explanation in most general favour at the moment is the double‐barrelled one of “picture‐palaces” and “cheap editions.” Whether or not this explanation is correct does not concern us greatly. But we must protest against the attitude being taken in so many places, that a decrease of any kind necessarily must be an evil. The work of a library cannot really be shewn by the total at the foot of a column of figures.

The study intends to develop guidelines for the communication and marketing policy of Swiss tourism service providers aiming at targeting the future senior citizen market. It is of an exploratory nature, and based on interviews with current senior citizens in Switzerland and a Delphi study with 30 experts from the Swiss tourism and hospitality sector, as well as specialists from senior citizen associations and research institutes. The results show the importance of the increasing request by senior citizens for learning experience through holidays. The different marketing strategies aimed at such clientele will be increasingly profiled according to the specific motivation and preferences of this clientele.

Recent years have seen an upsurge of interest in the study of emotions in organizations. Research, however, has been hampered by the ephemeral nature of emotions and a lack of an integrated multi-level model. This article therefore presents a five-level model of emotions in organizations. At the lowest level is within-person variation, defined in terms of affective events theory. Levels of the model then proceed through individual, dyadic relationship, group, and organization-wide perspectives. The article also outlines the neurophysiological processes that underlie the experience, perception, and communication of emotion; it concludes with a discussion of implications for research and practice.

The purpose of this paper is to propose a novel jump control method based on Two Mass Spring Damp Inverted Pendulum (TMS-DIP) model, which makes the third generation of hydraulic driven wheel-legged robot prototype (WLR-3P) achieve stable jumping.

First, according to the configuration of the WLR, a TMS-DIP model is proposed to simplify the dynamic model of the robot. Then the jumping process is divided into four stages: thrust, ascent, descent and compression, and each stage is modeled and solved independently based on TMS-DIP model. Through WLR-3P kinematics, the trajectory of the upper and lower centroids of the TMS-DIP model can be mapped to the joint space of the robot. The corresponding control strategies are proposed for jumping height, landing buffer, jumping attitude and robotic balance, so as to realize the stable jump control of the WLR.

The TMS-DIP model proposed in this paper can simplify the WLR dynamic model and provide a simple and effective tool for the jumping trajectory planning of the robot. The proposed approach is suitable for hydraulic WLR jumping control. The performance of the proposed wheel-legged jump method was verified by experiments on WLR-3P.

This work provides an effective model (TMS-DIP) for the jump control of WLR-3P. The results showed that the number of landing shock (twice) and the pitch angle fluctuation range (0.44 rad) of center of mass of the jump control method based on TMS-DIP model are smaller than those based on spring-loaded inverted pendulum model. Therefore, the TMS-DIP model makes the jumping process of WLR more stable and gentler.

This study aims to analyze driver risks in the driving environment. A complete analysis of context aware assistive driving techniques. Context awareness in assistive driving by probabilistic modeling techniques. Advanced techniques using Spatio-temporal techniques, computer vision and deep learning techniques.

Autonomous vehicles have been aimed to increase driver safety by introducing vehicle control from the driver to Advanced Driver Assistance Systems (ADAS). The core objective of these systems is to cut down on road accidents by helping the user in various ways. Early anticipation of a particular action would give a prior benefit to the driver to successfully handle the dangers on the road. In this paper, the advancements that have taken place in the use of multi-modal machine learning for assistive driving systems are surveyed. The aim is to help elucidate the recent progress and techniques in the field while also identifying the scope for further research and improvement. The authors take an overview of context-aware driver assistance systems that alert drivers in case of maneuvers by taking advantage of multi-modal human processing to better safety and drivability.

There has been a huge improvement and investment in ADAS being a key concept for road safety. In such applications, data is processed and information is extracted from multiple data sources, thus requiring training of machine learning algorithms in a multi-modal style. The domain is fast gaining traction owing to its applications across multiple disciplines with crucial gains.

The research is focused on deep learning and computer vision-based techniques to generate a context for assistive driving and it would definitely adopt by the ADAS manufacturers.

As context-aware assistive driving would work in real-time and it would save the lives of many drivers, pedestrians.

This paper provides an understanding of context-aware deep learning frameworks for assistive driving. The research is mainly focused on deep learning and computer vision-based techniques to generate a context for assistive driving. It incorporates the latest state-of-the-art techniques using suitable driving context and the driver is alerted. Many automobile manufacturing companies and researchers would refer to this study for their enhancements.

The purpose of this paper is to explore and describe online communication about the experiences and attitudes toward Swedish Healthcare Direct, a national telephone advice nursing (TAN) service.

A descriptive research design was adopted using a six-step netnographic method. Three Swedish forums were purposefully selected and data from the virtual discussions were collected.

Three themes emerged: expectancy and performativity of the nurses, absurdity in accessibility and the scrutinizing game. The most prominent finding was the scrutinizing game, which included aspects of bidirectional mistrust from both nurses and callers. Another salient finding was the attitudes that callers held toward nurses who used a technique interpreted as “passing the buck.”

The use of a nethnographic method is novel in this area of research. Consequently, the body of knowledge has regarding telephone advise nursing service has significantly been broadened. A limitation in this study is that demographic data for the posters are not available.

Bidirectional distrust is an important issue that must be acknowledged by TAN services, since it might damage the service on a fundamental level. Healthcare providers, politicians, and researchers should account for the power and availability of virtual discussions when seeking consumers’ opinions and evaluating the quality of the care provided.

This analysis of the ongoing discussions that take place on the internet provides insight into callers’ perceptions of a national TAN service. The bidirectional mistrust found from both the nurses and the callers might be a threat to callers’ compliance with the advice given and their care-seeking behavior.