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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 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.

This paper presents the result of a document review on leisure and travel developments in mature Central European markets. Based on an extensive analysis of (1) socio‐demographic developments, (2) developments with regard to changing values, (3) developments with regard to the economic framework, (4) the future role of work, leisure and allocation of time here fore, (5) consumption trends, and (6) a number of singular other issues, implications for the tourism industry are drawn: (1) There is an increasing international standardisation (homogenisation) of basic service factors in terms of infrastructure and key service elements functionality, coupled with differentiating efforts in terms of specific service elements and experiences provided. (2) Due to and based on network advantages, future quantitative growth is basically triggered by large supply networks and travel corporations. (3) Growth will further take place at best suitable destinations in terms of securing time efficiency of travel experience, multi optionality of supply and international level of quality.

The purpose of this project was to create a contemporary taxonomy of Career and Technical Education (CTE) teacher competencies in order to evaluate and improve CTE teacher education.

This study utilized a modified Delphi technique with a large sample of CTE experts – teachers, administrators, and teacher‐educators in the state of Michigan, USA to identify the competencies and their relative importance.

As a result, new competencies were added and a number of old competencies were deleted or changed. The product of this research is a matrix of 144 competencies in 13 categories, which also shows the level of importance and degree of consensus for each competency.

The state plans to use the new competencies for a variety of purposes, however caution is advised for making conclusions and generalizations from the study for other applications.

Using the matrix as its infrastructure, CTE teacher‐education institutions can assess their curricula to determine where the competencies are addressed, and use it in the form of a follow‐up survey with recent graduates. CTE administrators might utilize the competencies for internal evaluation of new teachers and as a needs assessment for professional development.

Any effort to improve CTE teaching and teacher‐education, by researchers or policy‐makers, should begin with a consensus on the competencies required for successful teaching and learning.