New design of large fully-steerable radio telescope reflector based on homogenized mesh structure

The self-weight of a large fully-steerable radio telescope is one of the important factors affecting its performance. In the existing reflector system scheme, the problem of surface accuracy caused by its large and heavy structure has seriously restricted the application and implementation of large radio telescopes. Therefore, a new mesh structure scheme for a large fully-steerable radio telescope reflector is proposed in this paper. This scheme is based on a homogenized mesh back-up structure in the form of a quasi-geodesic grid and regular quasi-tri-prism or tetrahedron, which can significantly reduce the structural complexity and self-weight of the reflector under the condition that the reflector can meet the desired performance requirements. Finally, the feasibility and rationality of the scheme are evaluated by numerical simulation analysis, which has significant advantages and provides a new design for the reflector of a large fully-steerable radio telescope.

SYNTACTIC CONCEPT OF BEING AN OBJECT ATTRIBUTE

In our work, we proceed from the fact that syntactic structural schemes have a sign nature and their signified-syntactic concepts. Our article is based on the concept of the existence of typical propositions that have been fixed using syntactic constructions (positional and structural schemes of a simple sentence). The article defines the relationship between the syntactic concept and the sentence structure scheme in modern scientific research from the point of view of the linguocognitive approach; the definitions of the concepts "syntactic concept" and "sentence structure scheme" are presented; a linguocognitive approach to the study of sentence structure schemes through the prism of syntactic concepts is considered, the problems of interaction of syntax and semantics, as well as the principles of their interaction in the process of sentence analysis are considered. The article identifies the main syntactic schemes that represent the concept of the attribute of being an object, the basis of which is the verbs of being+object attribute.

Selection of the Optimal Load Bearing Wing Structure Scheme for an Unmanned Aerial Vehicle

This article presents the results of optimization of the load bearing structure of the wing of an unmanned aerial vehicle. The criteria and optimization parameters were considered, respectively: the minimum wing mass, number of spars and ribs, location parameters of the spars and ribs, and thickness of the wing's load bearing elements. The maximum wing deflection was considered as a limiting factor. The calculated model took into account the change in the thickness of the spars along the direction of the wingspan, while the thickness of the skin and ribs was considered as constant. The optimal load bearing scheme of the wing was selected by the criterion of the minimum wing mass based on the maximum permissible deflection of the wing. Calculations of the stress-strain state of the wing were performed using a finite element model in the FEMAP software package.

Experimental research and floating gait planning of crablike robot

In order to improve the swimming performance of a paddle-propelled crablike robot, the sequence and parameters of swimming gait are planned according to the bionic swimming mechanism. Based on the bionic prototype of Portunus trituberculatus, the structure scheme of a leg–paddle hybrid driven robot is proposed with the functions of walking on land, crawling on seabed, and swimming underwater. By analyzing the underwater propulsion mechanism of single paddle and hydrodynamic performance of double paddles cooperatively propulsion, four direct swimming gaits are planned and the corresponding attitude changes are theoretically analyzed. Then, the numerical simulation and direct swimming experiments are carried out to verify the effectiveness of proposed gaits and correctness of force analysis. In alternate swimming gait of lift-based mode, the robot swims forward in a rolling attitude, with an advantage of the minimum water resistance and the optimum swimming velocity and efficiency. The influence of flapping frequency and relative phases of paddles on the swimming velocity shows the trend of raise first and then fall.

Cluster based Energy Efficient multipath Routing in WSN

A wireless sensor network (WSNs) is made out of a huge gathering of sensor nodes with restricted assets as far as battery supplied energy. Consequently, the plan of an energy-efficient and extensible routing protocol is a critical worry for WSN applications. In this paper, we propose a novel improved Cluster based energy efficient multipath routing protocol (ICEEMRP) is utilized for energy efficient selection and reselection of CH for multipath routing to transfer the data from source to destination efficiently and simultaneously improving network lifetime. The proposed work take up an improved multipath structure scheme in order to accomplish the balance of the network energy utilization. The proposed plan also plays out the aggressive calculations for parameters, like, packet delivery ratio, energy utilization, network lifetime, and network overhead. The results shows that there is an enormous amount of energy saved in the network and hence improved network lifetime compared to conventional routing techniques

Debt And Equity-Based Financing, Size And Islamic Banks Profitability: Empirical Evidence From Indonesia

<em></em><em></em><p><em>Islamic</em><em> Banking as a financial institution functions to collect and distribute funds to the public. To carry out these functions, the capital structure scheme uses debt and equity based financing. In addition, the implementation is also influenced by the size which ultimately affect the performance of Islamic banking.</em><strong><em> </em></strong><em>This study aims to examine debt and equity-based financing, size and Islamic banks profitability: empirical evidence from Indonesia. The research method used is model estimation test of Moderated Regression Analysis (MRA) to see size as moderation variable. Banks profitability is represented by ROA and ROE. This study uses Islamic bank panel data from financial reports published during the sample period covering 2008-2017. The empirical findings show that debt and equity-based financing affect banks profitability. </em><em>Furthemore</em><em>, bank size does not moderate the debt and equity-based financing relationship to Islamic banks profitability.</em><strong></strong></p><p><strong><em></em></strong><em><br /></em></p>