Analysis on the characteristics of domestic and foreign blue economy research based on CiteSpace

Blue economy is one of the hot research topics both at home and abroad,which is of great significance to the construction of a strong maritime country and the high-quality development of national economy.This paper summarizes the research highlights and characteristics of blue economy at home and abroad,based on the visual analysis of analyzing 414 literature from Web of Science Core Collection Database(SSCI)and CNKI General Database,using CiteSpace 6.1.R3.The results show that:(1)The number of articles in the field of blue economy at home and abroad is on rise during 2010-2021,and the volume of foreign articles about blue economy is significantly higher than that of domestic ones.The domestic and foreign articles about blue economy were more of a theoretical mechanism research.(2)Domestic blue economy cooperation network is budding,blue economy research in coastal provinces and cities of China has policy support and scientific research advantages,and Ocean University of China is the core institution in the research field of blue economy in China.With close international blue economy network cooperation,the university is the main scientific research unit of blue economic cooperation at home and abroad.United States,the United Kingdom and Australia attach great importance to blue economy and have a good scientific research foundation,holding an absolutely dominant position in the field of blue economy research.(3)Blue industry and blue practice are the hot research topics of China's blue economy,and the evolution of research topics can be divided into three phases.Among other topics,regional analysis,sustainable blue economy,ocean governance,are the priority research areas of international blue economy research.

An Experimental Research to Study the Microwaves transmission Characteristics of Ablating Material in Arc-Heated Plasma Flow

in this paper, an experimental research the effect of ablating material on the reflection and the transmission of microwaves in arc-heated plasma flow is presented by using the C band microwave measuring system. The results show that the ablating material with accidented surface and its high temperature have remarkably affected the reflection and the transmission of microwaves. The experiment proves that the system has outstanding precision and reliability.

CHARACTERISTICS OF STRENGTH CONTROL OF ADAPTIVE STRUCTURE WITH ELECTROMECHANICAL COUPLING

Based on the programming method, an electromechanical coupling adaptive statically indeterminate truss structure is controlled for increasing its load capacity. Several main parameters during the process of design of the adaptive structure are selected for a study of its characteristic during the control stage. The curves of each parameter for the effect of control results are plotted and corresponding conclusions are drawn. Thus, the theoretical basis is presented for optimal design, manufacture and control of the adaptive structure.

A New Kind of Pilot Controlled Proportional Direction Valve with Internal Flow Feedback

Proportional direction valve is one of the most fundamental elements in electronic-hydraulic control technique. Its function is to control the operating speed, direction, position, and strength of output force of the hydraulic actuator continuously. Considering the different application and the cost, the existing technique mainly includes the internal feedback valve used in open loop system, and the electronic closed loop controlled valve used in closed loop system. Because of their different mechanical structure and the gre at different in performance, it brings inconvenience for customer to select, also inconvenience for enterprise to produce. Aiming at this problem, the idea of combining the above two kinds of valves into one body is proposed first, and then the new valve＇s structure to realize this target is designed. The idea intends to apply the displacement pilot flow feedback control principle in present 2-position 2-way valve system to the proportional direction valve of 3-position 4-way system. Newly designed feed forward controller can decouple the interference between the internal feedback and the electronic closed loop. Redundant conversion is designed to electronic switch mode. Experiment on dynamic and static characteristic of new proportional direction valve in internal feedback control mode and electronic closed loop control mode is discussed to prove the new theory is correct. Although the new valve is of excellent dynamic response characteristic, its steady control characteristic in open loop control mode needs to be improved further. The research results prepare one new fundamental element for electronic-hydraulic control technology.

Experimental analysis of high temperature capacitance variance of MLCC

High temperature capacitance variance of multi-layer ceramic capacitor （MLCC） is researched.Combined with the characteristics of MLCC,the application of MLCC in fuze is proposed,and the temperature stability of MLCC is also discussed.The experimental results indicate that the capacitance of low frequency MLCC is largely affected by temperature.

龙口矿区2号煤层顶板粘土岩特征及研究意义

本文在详实调查和实验分析基础上，论述了2号煤层顶板粘土岩的特征，并指出了此研究在矿产综合利用和巷道工程管理中的实用意义。

Research on the temperature characteristic of Love wave device with structure of multi-waveguides used for gas sensor

This paper aimed at extracting optimal structural parameters for Love wave device with structure of multi-waveguides to improve its temperature stability. The theoretical model dealing with the Love wave propagation in multi-waveguides was established first, the dispersion characteristic is depicted by the acoustic propagation theory of stratified media and boundary conditions. Combing with the dispersion characteristics and Tomar＇s method, the optimal structural parameters for the Love wave device with zero temperature coefficient were extracted, and confirmed by the following experimental results. Excellent temperature coefficient of the Love wave device with SU-8/SiO2 on ST-90°X quartz substrate was evaluated experimentally as only 2.16 ppm/℃, which agrees well with the calculated results. The optimized Love wave device is very promising in gas sensing application.

Research on acoustic emission characteristics of local corrosion on Q235 steel

To solve the problem of corrosion acoustic emission （AE） source feature extraction and recognition, the AE detection validation and the amplitude-frequency characteristics were derived in theory. The amplitude of AE signal generated by bubble burst is proportional to its radius square and the liquid level, while the AE signal frequency is inversely proportional to the bubble radius. The AE signal amplitude of the steel and the steel corrosion product cracking is proportional to the local stress, and the AE signal frequency is proportional to the crack propagation velocity and inversely proportional to the crack propagation distance. Three Q235 specimens were separately immersed in the solution of 10% FeC13.6H20, 5% CuSOa.5H20 and 10% FeC13.6H20 with 0.01 mol/L HCL. The AE systems with high frequency and low frequency were used to detect the whole corrosion process AE signals. The AE signals of Q235 steel and the steel corrosion products cracking were detected as the verification experiment. The AE signals from different sources could be distinguished by AE hits count and the power spectrum. It is coincident with theoretical analysis. These conclusions have significant guidance for the corrosion detection and evaluation by on-line acoustic emission detecting.

Object-Oriented Analysis of ELIMINO

ELIMINO is a mathematical research system developed for theimplementation of Wu's method, a powerful method for polynomial equation systemsolving and geometric theorem proving. The aim of ELIMINO is to provide usera programmable interpreting environment to use Wu's method in scientific researchand engineering computation. In this paper, the development of ELIMINo systemis outlined and the techniques adopted are discussed, then some details about theobject-oriented analysis of ELIMINO are presented.