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Crack sensor based on RFID tag has become a research hotspot in the field of metal structural health monitoring for its significant benefit of passive wireless transmission. While in practice, crack location will impact the performance of crack depth-sensing tag. The purpose of this paper is to provide a method for reducing disturbance of crack location on crack depth-sensing tag.

The effect analysis of crack location on crack depth-sensing tag is presented first to find disturbance reason and disturbance law. On the basis of that, a miniaturized tag is proposed to improve the current distribution and reduce the disturbance introduced by crack location.

The degree of crack location disturbance is closely related to the current distribution in the coverage area of tag. Because sensing tag performs better when crack locates in the high current density area, miniaturization of sensing tag is exploited to expand the high current density area and make the area more symmetrical. The simulated and experimental results demonstrate that tag miniaturization can enhance the performance of crack depth-sensing tag.

This paper provides a method to enhance the performance of crack depth-sensing tag.

RFID tags for sensing are available to operate and transmit sensing data to measurement equipment without battery and wires, which is a great advantage in establishing IoT environment. For crack sensing tags, however, the short service life of tags restricted their application. This paper aims to introduce a method of surface crack detection and monitoring based on RFID tag, which makes it possible for tags to be reused.

Metal plate to be monitored, acting as the ground plane of microstrip patch antenna, is underneath the crack sensing tag. The propagating surface crack in metal plate will change the electric length of tag’s antenna that is directly proportional to the crack depth and length. Thus, the deformation of sensing tag introduced by the load on metal structure is no longer a prerequisite for crack sensing.

The simulated and experimental results show that the proposed crack sensing tag can sense the change of surface crack with mm-resolution and sense surface crack propagation without a deformation, which means the proposed crack sensing tag can be reused.

The key advantage of the proposed method is the reusability of the RFID tags.

Radio frequency identification tags for passive sensing have attracted wide attention in the area of Internet of Things (IoT). Among them, some tags can sense the property change of objects without an integrated sensor, which is a new trend of passive sensing based on tag. The purpose of this paper is to review recent research on passive self-sensing tags (PSSTs).

The PSSTs reported in the past decade are classified in terms of sensing mode, composition and the ways of power supply. This paper presents operation principles of PSSTs and analyzes the characteristics of them. Moreover, the paper focuses on summarizing the latest sensing parameters of PSSTs and their matching equipment. Finally, some potential applications and challenges faced by this emerging technique are discussed.

PSST is suitable for long-term and large-scale monitoring compared to conventional sensors because it gets rid of the limitation of battery and has relatively low cost. Also, the static information of objects stored in different PSSTs can be identified by a single reader without touch.

This paper provides a detailed and timely review of the rapidly growing research in PSST.

Epoxy zinc-rich coatings are widely used in harsh environments because of the long-lasting cathodic protection of steel surfaces. The purpose of this paper is to use flake zinc powder instead of the commonly used spherical zinc powder to reduce the zinc powder content.

In this paper, the authors have prepared an anticorrosive zinc-rich coating using a flake zinc powder instead of the conventional spherical zinc powder. The optimal dispersion of scaly zinc powder in zinc-rich coatings has been explored by looking at the surface and cross-sectional morphology and studying the cathodic protection time of the coating.

The final epoxy zinc-rich coating with 35 Wt.% flake zinc powder content was prepared using sand-milling dispersions. It has a similar cathodic protection time and salt spray resistance as the 60 Wt.% spherical zinc-rich coating, with a higher low-frequency impedance modulus value.

This study uses flake zinc powder instead of the traditional spherical zinc powder. This reduces the amount of zinc powder in the coating and improves the corrosion resistance of the coating.

The purpose of this paper is to enhance the compatibility of titanium dioxide in epoxy resins and thus the corrosion resistance of the coatings.

In this work, TiO₂ was modified by the mechanochemistry method where mechanical energy was combined with thermal energy to complete the modification. The stability of modified TiO₂ in epoxy was analyzed by sedimentation experiment. The modified TiO₂-epoxy coating was prepared, and the corrosion resistance of the coating was analyzed by open circuit potential, electrochemical impedance spectroscopy and neutral salt spray test.

High-temperature mechanical modification can improve the compatibility of TiO₂ in epoxy resin. At the same time, the modified TiO₂-epoxy coating showed better corrosion resistance. Compared to the unmodified TiO₂-epoxy coating, the coating improved the dry adhesion force by 61.7% and the adhesion drop by 33.3%. After 2,300 h of immersion in 3.5 Wt.% NaCl solution, the coating resistance of the modified TiO₂ coating was enhanced by nearly two orders of magnitude compared to the unmodified coating.

The authors have grafted epoxy molecules onto TiO₂ surfaces using a high-temperature mechanical force modification method. The compatibility of TiO₂ with epoxy resin is enhanced, resulting in improved adhesion of the coating to the substrate and corrosion resistance of the coating.

Since carbon nanotubes (CNTs) were discovered by Iijima in 1991, they have gained more and more attention by people because of their unique physical and chemical properties. The CNTs have one-dimensional nanostructure, high surface adsorption capacity, good conductivity and electronic ballistic transmission characteristics and therefore have excellent mechanical, electrical, physical and chemical properties. CNTs are ideal basic materials to make nanometer gas sensors. Nanometallic materials function as to enhance electrode activity and promote the electron transfer, so if composite nanometallic materials M (such as Au, Pt, Cu and Pd) and CNTs are used, all kinds of their characters of components would have coeffect. Electrochemical sensors by use of such composite as electrode would have a higher detection sensitivity.

CNTs were synthesized via chemical vapor deposition technique and were purified afterward. CNTs-M(Pt,Au) suspension was prepared by chemical deposition using spinning disc processor (SDP) and was coated on gold electrode. The modified electrodes were constructed, based on immobilization of glucose oxidase on an Au electrode by electrostatic effect. CNTs-Pt/ glassy carbon electrodes (GCE) electrodes were made by electrochemically deposition of platinum particles on GCE modified by CNTs. The microstructures of the harvested CNTs, CNTs-M (M = Au, Pt) were analyzed under scanning electron microscopy and transmission electron microscopy. The application of the sensor in medical detection has been evaluated.

The results shown that CNTs-Au biosensors exhibit good reproducibility, stability and fast response to glucose detection, it can be used in the clinic detection of glucose concentration in human serum. Using CNTs-Pt/GCE for formaldehyde detection exhibited high sensitivity and good reproducibility.

This study modified CNTs by using self-assembled techniques through SDP with nano Pt and Au by electrodeposition for the first time. CNTs-Pt/GCE electrode was prepared by depositing platinum particles electrochemically on GCE modified by CNTs. CNTs-Au-modified electrode was prepared by immobilization of glucose oxidase on an Au electrode first by electrostatic effect. Electrochemical behaviors of glucose at CNTs-Au and formaldehyde at CNTs-Pt/GCE were investigated by cyclic voltammetry.

To setup a theoretical model for grasping cutting pieces of garment better, which will help to design a special soft gripper and push forward the automated level of garment manufacturing.

This paper first analyzed the mechanics of the grasping process and concluded the main factors that affect the success of grasping. A theoretical model named grasping fabric model (GFM) was constructed to show the mechanical relationship between the soft gripper and the fabric pieces. Subsequently, two fabric samples were selected and tested for their friction properties and critical buckling force, and the test data were substituted into the theoretical model GFM to obtain the grasping parameters required for fabric grasping layer by layer.

It was found that (1) the critical buckling force of the fabric is mainly influenced by the bending stiffness and the deformation length of the fabric during grab. (2) The difference between the friction between the soft gripper and the fabric and the friction between the fabric, that is DF1-2, has an important influence on the accuracy of grasping layer-by-layer.

It showed that the grasping parameters provided by GFM enable the two samples to be more effectively separated layer by layer, which verifies that the GFM model is strong enough for the possible application in garment automated production.

In order to analyze the level of independent controllability and its evolution of high-end equipment manufacturing industry from Jiangsu Province, this article introduces the dual-excitation control line method to construct a comprehensive evaluation model for independent controllability.

Through the collection of information of high-end equipment manufacturing industry's independent and controllable capabilities on different indicators, the three aspects of advancement, autonomy and controllability, an empirical evaluation of 10 enterprises in the high-end equipment cluster in Jiangsu Province was conducted in terms of advancement, autonomy and controllability.

It effectively reveals the area and evolution characteristics of the “reward” and “punishment” of different indicators of each representative enterprise and reflects the development status and different characteristics of each representative enterprise on the three indicators. The research results provide decision-making guidance for enterprises in the management and control of advanced manufacturing systems with independent and controllable capabilities.

Existing research focuses on the evaluation of enterprises' independent controllability only on a single angle or index. This paper maps the dynamic evaluation problem of multiple time-point data to the evaluation problem of single time-point multi-index data and investigates the fluctuation of the performance of the same enterprise under different indexes, so as to comprehensively evaluate the independent controllable level of high-end equipment manufacturing industry and analyze the reasons. Further, this paper first establishes an evaluation index system of independent controllable level of high-end equipment manufacturing industry and quantitatively measures the advanced, independent, controllable and other aspects of typical enterprises in this industry by constructing a double incentive control line evaluation model.

The purpose of this paper is twofold to examine the factors that contribute to local bias of venture capital in China and to explore the relationship between local bias and performance of venture capital institutions.

Local bias was measured in line with the model developed by Cumming and Dai (2010). Regression techniques were performed for our long-term cross-sectional data to analyse the potential determinants of local bias. This is followed by the Probit model to test the relationship between local preference and successful exit.

The overall finding indicated that local bias in China increased over time. The stiff competition among venture capital institutions reduced local bias, but the enhanced innovation capabilities of a particular geographical area amplified local bias because of the knowledge spillover effect. Finally, the results suggested that venture capital institutions with less local bias enjoy a greater likelihood of making successful exits.

This study used successful venture capital exit as a proxy for venture capital institution’s performance because of the unavailability of information such as internal rate of return. Future research should try to adopt other way of measuring venture capital institution’s performance.

This study sheds light on the various possible causes of local bias that the policymakers need to be aware of. Despite the rapid rise of China’s venture capital market in recent years, venture capital institutions have yet to make inroads into the local high-tech industry. This study implies to the policymakers that to reverse this trend, they should formulate policies that foster the long-term performance of venture capital institutions, mitigate the severity of local bias and raise the competitiveness of the Chinese venture capital market.

Because of data limitations, there is currently lack of prior empirical research on local bias of Chinese venture capital institutions based on large-scale data. This study intends to fill the gap.

This paper aim to investigate the influence of PA on the corrosion behavior of carbon steel with blast cleaned or pre-rusted treatments, and interpret the inhibition mechanism of PA on the steel with different surface treatments.

The influence of PA on the corrosion behavior of blast cleaned or rusty steel was investigated by means of electrochemical impedance spectroscopy (EIS). The EIS data were analyzed using the @ZsimpWin commercial software. The morphology and component of steel after immersion were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), Fourier transformation infrared (FTIR) and X-ray diffractometer (XRD).

EIS analysis results indicated that PA had good corrosion inhibition for blast cleaned or rusty steel. SEM, EDS, FTIR and XRD further indicated that PA had two main corrosion inhibition processes for the corrosion inhibition of blast cleaned or rusty steel: corrosion dissolution and formation of protective barrier layers.

Most published works focus the attention only toward the effect of corrosion inhibitor for the clean metal surfaces. However, the surface condition of metal sometimes is unsatisfactory in the practical application of corrosion inhibitor, such as existing residual rust. Some studies also have shown that several corrosion inhibitors could be applied on partially rusted substrates. These inhibitors mainly include tannins and phosphoric acid, but not PA. Therefore, the authors investigated the influence of PA on the corrosion behavior of carbon steel with blast cleaned or pre-rusted treatments in this paper.