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IF the plane of symmetry of the wheel is the same in both its landing and retracted positions, retraction is achieved by simple rotation about an axis which is perpendicular to the plane of the wheel.

The field of nonmarket strategy has expanded rapidly over the past 20 years to provide theoretical and practical guidance for managers seeking to influence policymaking. Much of this scholarship has built directly on spatial and “pivotal politics” models of lawmaking. While extremely helpful at identifying crucial targets for lobbying, these models treat all policymakers as identical in their abilities to advance legislative agenda items through various policymaking hurdles. We build upon these earlier models, but include policymakers who vary in their relative effectiveness at advancing measures through the legislative process. We identify how the implications of our model deviate from those of conventional (pivotal politics) analyses. We then present an empirical strategy for identifying effective Lawmakers in the United States Congress, and illustrate the utility of this approach for managers developing nonmarket strategies in legislative institutions, relying on the case of banking and financial services reforms between 2008 and 2011.

Knowledge concerning the meaning of the object of learning is an important contribution of Learning study. The purpose of this paper is to generate this kind of knowledge and show how it can be developed and refined in the different phases of a Learning study.

The paper reports on a Learning study in primary technology education conducted with students aged six to seven years old, with the aim to explore a specific object of learning; to construct a linkage mechanism for transferring and transforming movement.

The findings show several aspects to discern by the learner in order to grasp the object of learning and reveal how this knowledge was gradually developed during the Learning study. The presumed aspects, those identified in the pre- and post-test, as well as how they were elaborated in the lesson contributed to refining the meaning of the object of learning.

In Learning study, knowledge concerning the meaning of the object of learning is generated. By empirically demonstrating the development and specification of this knowledge during a Learning study, this paper will contribute to the discussion of knowledge products from Learning studies as well as to knowledge concerning what there is to know in order to develop a specific capability in technology education.

This study aims to summarize the trend and overall aspect of Circular Economy (CE) in supply chain management research as a contribution of the previous research towards the CE concept narrowed in perspective, without presenting a specific application. Further, it is explored to identify the research hotspot, knowledge base, topic, landmark and pivot point in this research.

The scientometric mapping of CE in supply chain research papers is analyzed using VOSviewer and CiteSpace software to cover the broader field spectrum and overcome a manual review. The Research papers are extracted from the Web of Science core collection comprising keywords “Circular Economy*” and “Supply Chain*”. A number of 1,092 papers are selected from the reputed journals over 20 years (2001–2021) for review.

The co-operation visualization network analysis initially identifies the descriptive analysis of overall publications, leading authors, countries, institutions and journal sources. The co-occurrences of keywords present the research hotspot. Moreover, the co-citation cluster analysis identifies knowledge base, research topic, landmark and pivot point. Industry 4.0 integrated supply chain, their driver, barrier, challenges and risks need further investigation.

The findings are based on networks visualization analysis principles, which indicate connection, quality and impact of academic works that might be open to accusations. The methodology chosen for the research and findings interpretations are based on researchers' perceptive limitations and subjective judgment.

This review paper covers a diverse view to attain sustainable development goals due to considerable attention from researchers, practitioners and policymakers. Also is expected to set the future direction of the CE in the supply chain research.

The purpose of this paper is to describe a robot vision system which put rings on hooks that are moving freely on a conveyor belt. The hook can show a significant swinging which can be well approximated by a pendulum movement. The problem is of large relevance for many industrial applications and the challenge is to compute a 3D pose that is sufficiently precise to allow for successful placements of the rings.

This requires a fast and precise tracking and a compensation for latencies connected to the processing of visual information as well as the actual robot action.

The authors achieve this through a precise pose estimation in a high‐resolution stereo setup, as well as a modeling of the hook movement as a combination of a translational and a pendulum movement.

The paper shows that under normal conditions close to 100 percent success can be achieved such that this technology now can be transferred into industrial systems.

Cycloidal rotors, also known as cyclogyros, are horizontal axis rotary-wing machines with potential for Vertical Take-Off and Landing aircraft applications. The paper aims to devise and validate a new semi-empirical analytical model that is capable of assisting in the structural and aerodynamic design of cyclogyros.

The analytical model comprises a purely analytical kinematic sub-component that is used for analyzing the structural feasibility of the rotor. Several geometrical parameters are assessed, e.g. the oscillation schedule of the blades as a function of the properties of the pitching mechanical system. The dynamic sub-component of the model is used for estimating the rotor thrust production and power consumption. This sub-component is semi-empirical and uses a calibration function that was devised using the available experimental data.

For a set of initial conditions and geometrical parameters, the model is capable of providing a real animation of the cyclogyro operation. It is shown that the motion of the blades does not comply with the requirements of a perfect cycloidal curve. The study concerning the simulation of the virtual camber effect on the drum blades, with and without the pitch effect, shows that the virtual camber strongly depends on the chord-to-radius ratio and on the aircraft advance velocity.

A new analytical model capable of assisting in the geometrical and aerodynamic design of cyclogyros is here proposed. The model is capable of providing approximate estimations of the cyclogyro thrust production and power consumption under operating design conditions.

Flight control mechanism for an airplane, comprising a pivotally supported control surface with a hinged boost tab thereon, means for swinging the control surface for airplane manoeuvring purposes, comprising an element mounted to rotate about an axis in coaxial relation with the pivot axis of the control surface, and an elongated torsional spring in concentric relation with said pivot axis of the control surface, having one end thereof fixedly connected to the element and its other end fixedly connected to said control surface, and adapted when the element is rotated while the control surface is subjected to low air resistance to swing said control surface conjointly with the element and further adapted when the element is rotated while the control surface is subjected to high air resistance to permit said element to rotate relatively to the control surface, and means operative in response to rotation of the element relatively to the control surface to tilt the tab into a position wherein it serves to assist in swinging the control surface.

The purpose of this paper is to investigate a dissipative reinforced concrete structural wall that can improve the behavior of a tall multi-storey building. The main objective is to evaluate the damage of a dissipative wall in comparison with that of a solid wall.

In this paper, a comparative nonlinear dynamic analysis between a dissipative wall and a solid wall is performed by means of SAP2000 software and using a layer model. The solution to increase the seismic performance of a reinforced concrete structural wall is to create a slit zone with short connections. The short connections are introduced as a link element with multi-linear pivot hysteretic plasticity behavior. The behavior of these short connections is modeled using the finite element software ANSYS 12. In this study, the authors propose to evaluate the damage of reinforced concrete slit walls with short connections using seismic analysis.

Using the computational model created in the second section of the paper, a seismic analysis of a dissipative wall from a multi-storey building was done in the third section. From the results obtained, the advantages of the proposed model are observed.

A simple computational model was created that consume low processing resources and reduces processing time for a dynamic pushover analysis. Unlike other studies on slit walls with short connections, which are focussed mostly on the nonlinear dynamic behavior of the short connections, in this paper the authors take into consideration the whole structural system, wall and connections.

THE General Dynamics)'Grumman F‐111 fighter is noteworthy on many counts: first, and most important in the context of coverage of variable sweep types in this issue, the F‐111 is the world's first variable sweep air‐craft to be designed and built for operational service. Second, the F‐111 represents the first successful attempt by the United States to design and build a multi‐mission aircraft suitable for service with both the United States Navy and the United States Air Force—obviously the F‐111 is not the first aircraft to become operational with more than one of the United States services (the McDonnell Phantom is currently in service with the U.S.A.F., the U.S. Navy and the U.S. Marines)—but it is the first to be designed from the initial concept to satisfy U.S.A.F. and U.S. Navy mission requirements. Thirdly, the existence of the F‐111 programme was directly responsible for the cancellation of the TSR‐2 programme because even though Britain's Government cur‐rently appear to be seeking an alternative replace‐ment for the cancelled TSR‐2 (in the form of an uprated Hawker Siddeley Buccaneer—designated the Buccaneer 2 Star—or an improved Dassault Mirage IV with two afterburning Rolls‐Royce Speys instead of the S.N.E.C.M.A. Atar turbo‐jets), it is doubtful if the TSR‐2 would ever have been cancelled had not the American Government offered Britain the opportunity of pur‐chasing the high‐performance multi‐mission F‐111 as a lower cost substitute. If the R.A.F. does re‐equip with the F‐111 instead of the TSR‐2 then in terms of performance, i.e. range, speed, weapons load, ability to survive at low level, ability to navigate to target in all weathers (day and night), ability to operate from short rudimentary airstrips and ferry range, the F‐111 should, with only mild reservations, fulfil all the mission profiles planned for the TSR‐2, and will offer attractive bonuses in addition. On the other hand, unless something approaching a complete redesign and rebuild of the Buccaneer or Mirage IV is carried out, neither aircraft can approach the performance of the TSR‐2.