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The purpose of this paper is to build a new deployable antenna with folded scissors ribs and to evaluate the reasonable characteristics of this new structure.

Based on the TerrStar-1 satellite, virtual design and shapes forming are considered in this paper with the structure design of the new antenna. Considering the relaxation units in net surface, form-finding evaluation is used to build mathematical model and operate the optimization algorithm so that the design of the new antenna with folded scissors ribs is achieved. Simulations are carried out to verify the antenna proposed.

It is found that the antenna with folded scissors ribs can be developed smoothly in the space.

The proposed the antenna with folded scissors ribs can be considered as a fall-back alternative for large antenna, with a diameter of over 10 m in the space, or is seen as another option for the system with a simple rigid structure.

Different from traditional antenna, it provides a valuable reference for the further research of large deployable antenna in space. The antenna in this paper is able to develop more than 30 m of diameter. Meanwhile, the surface density and the natural frequency and the root-mean-square error in surface are superior to those of the traditional antenna.

Information given applies to the Marks 1 to 5, the illustrations showing the Proctor 5. Differences between the Mk. 5 and earlier Mks. are described and, where possible, related to the illustrations. Information applies to all Marks unless otherwise stated.

In order to make the aperture of spatial deployable antenna larger, this paper proposed the study on a spatial annular tensegrity structure with 100 m large scale, which could be one of the ideal solutions to improve the dimension of the antenna. This study is aiming to figure out the dynamic characteristic of ultra-large annular tensegrity and address the problem of insufficient rigidity with local modes that many ring truss-type deployable antenna structures have faced.

This work is carried out based on the nonlinear dynamic modelling when fully considering the effect of bending and torsion deformation of beams, as well as the pretension of cables. Additionally, the structural stability analysis based on the proposed stability criterion is also presented to evaluate the tensegrity configuration with different distribution of cable groups.

This research results verify that the modified structure with radial ribs could eliminate the effect of the local vibration mode on stiffness and is suitable to meet the requirements of the annular tensegrity structure. Additionally, the calculation results demonstrate that the structural configuration of annular tensegrity with 36 groups of cables which share the nodes with radial ribs is more appropriate to enhance the stiffness and structural stability.

A new large annular tensegrity structure with radial ribs and tensioned cables is proposed. Based on the proposed structural configuration, the positive definiteness of the tangent stiffness matrix is carried out as the criterion of stability and the composition of the analytical expression of the tangent stiffness matrix is analyzed. Four levels of tensegrity structure stability have been carried out and the influence of the structural parameters on the stability and the rigidity has been analyzed. A scaled-down prototype is developed to verify the feasibility of the design of the hoop-column-rib configuration by the deployment and dynamic experiment.

AT the request of the Director‐General of the International Labour Office Mr. Petre Lupu, Rumania's Minister of Labour, has described the benefits brought to his country through setting up a Management Development Centre.

Students need to learn and practice creative thinking skills to ensure success in solving everyday, national, and global problems that include those affecting economic issues. The global economy requires workers to have research and innovation skills that depend upon creativity. However, many current educational programs focus mostly on factual content, doing little to inspire or apply the creative process. The project presented here shows an engaging activity that combines creative thinking skills with economic content. Although the activity occurred in a college course on creativity theory and practice, this challenging game can be easily adapted and embedded in the Kindergarten-12 social studies curriculum. This article discusses the set-up of the activity and its connection to creativity theory and curriculum standards. It showcases the work of eleven participants who each made a unique object or scene from a given set of craft and recycled materials, subsequently relating the resulting product to a current economic issue. Photographs of the resulting products are provided along with descriptions of the theme of each item, its connection to economics, and creative aspects of the work. Suggestions for adaptation to the Kindergarten-12 classroom are given.

Built as an integral component) Frames, stringers and stressed skin with integrally machined skin/stringer panels above the wing cut‐out. Entire shell pressurized, from front pressure bulkhead 2 to rear pressure bulkhead 33, at rear engine‐mounting, except for wing cut‐out and main and nose undercarriage bays

CLEARLY, I should have kept my trap shut last December, instead of expressing a hope for some snow over the Christmas holidays—in the month since then there has been little else descend from the skies, and my dear wife is already querying why we should spend vast sums of money on travelling to Austria in February for conditions readily available, as I write, on Hampstead Heath.

The autumn round of exhibitions produced a great deal to interest facilities managers. There was no office furniture in Milan, but Orgatechnik in Cologne saw the launch of what may well prove to be important additions to the office furniture systems market.

IT is a long time since The Life of Johnson defined man as a tool‐making animal, and the tools he used in those days were primitive when contrasted with the precise, complicated and sophisticated ones employed today. Early tools were really evolved through centuries as necessary extensions of a man's arms. A spade gave them leverage and a longer reach.

Supernumerary robotic limbs (SRLs) are a new type of wearable robot, which improve the user’s operating and perceive the user’s environment by extra robotic limbs. There are some literature reviews about the SRLs’ key technology and development trend, but the design of SRLs has not been fully discussed and summarized. This paper aims to focus on the design of SRLs and provides a comprehensive review of the ontological structure design of SRLs.

In this paper, the related literature of SRLs is summarized and analyzed by VOSviewer. The structural features of different types of SRLs are extracted, and then discuss the design approach and characteristics of SRLs which are different from typical wearable robots.

The design concept of SRLs is different from the conventional wearable robots. SRLs have various reconfiguration and installed positions, and it will influence the safety and cooperativeness performance of SRLs.

This paper focuses on discussing the structural design of SRLs by literature review, and this review will help researchers understand the structural features of SRLs and key points of the ontological design of SRLs, which can be used as a reference for designing SRLs.