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This study aims to investigate the corrosion inhibitor effect of migrating corrosion inhibitor (MCI) on Q235 steel in high alkaline environment under cathodic polarization.

This study investigated the electrochemical characteristics of Q235 steel with and without MCI by polarization curve and electrochemical impedance spectroscopy. Besides, the surface composition of Q235 steel under different environments was analyzed by X-ray photoelectron spectroscopy. In addition, the migration characteristic of MCI and the adsorption behavior of MCI under cathodic polarization were studied using Raman spectroscopy.

Diethanolamine (DEA) and N, N-dimethylethanolamine (DMEA) can inhibit the increase of Fe(II) in the oxide film of Q235 steel under cathodic polarization. The adsorption stability of DMEA film was higher under cathodic polarization potential, showing a higher corrosion inhibition ability. The corrosion inhibition mechanism of DEA and DMEA under cathodic polarization potential was proposed.

The MCI has a broad application prospect in the repair of damaged reinforced concrete due to its unique migratory characteristics. The interaction between MCIs, rebar and concrete with different compositions has been studied, but the passivation behavior of the steel interface in the presence of both the migrating electric field and corrosion inhibitors has been neglected. And it was investigated in this paper.

The purpose of this study is to investigate the characteristic and function of oxide film formed on grinding wheel in electrolytic in-process dressing (ELID) precision grinding and improve the quality of ELID grinding.

Dynamic film forming experiments were carried out with a simulation device close to the actual processing conditions. Then, the ELID grinding experiments of bearing rings were performed using grinding wheels with good film forming effect. The experiment was designed by quadratic regression general rotation combination method. The influence of grinding depth, electrolytic voltage, duty cycle and grinding wheel linear speed on grinding effect is analyzed.

A mathematical model for the formation rate of oxide film was established. The experiments show that the composition of grinding wheel and grinding fluid, as well as the electrical parameters, influence the film forming effect. Thus, the oxide film plays an important role in ELID grinding.

This study provides a reference for the design and selection of grinding wheel and grinding fluid and the setting of process parameters in ELID grinding.

The purpose of this paper is to understand what inhibit or facilitate cloud computing (CC) assimilation.

The authors investigate the effects of two enablers, top management support (TMS) and government support (GS), and two inhibitors, organization inertia (OI) and data security risk (DSR) on CC assimilation. The authors posit that enablers and inhibitors influence CC assimilation separately and interactively. The research model is empirically tested by using the field survey data from 376 Chinese firms.

Both TMS and GS positively and DSR negatively influence CC assimilation. OI negatively moderates the TMS–assimilation link, and DSR negatively moderates the GS–assimilation link.

The results indicate that enablers and inhibitors influence CC assimilation in both separate and joint manners, suggesting that CC assimilation is a much more complex process and demands new knowledge to be learned.

For these firms with a high level of OI, only TMS is not enough, and top managers should find other effective way to successfully implement structural and behavioral change in the process of CC assimilation. For policy makers, they should actively play their supportive roles in CC assimilation.

A new framework is developed to identify key drivers of CC assimilation along two bipolar dimensions including enabling vs inhibiting and internal vs external.

The purpose of this paper is to achieve accurate integrated navigation results for the unmanned aerial vehicle (UAV) systems even in the presence of possible navigation faults in the subsystems of the federated Kalman filter.

The federated Kalman filter is modified from two aspects to get accurate navigation results under abnormity. First, time-variant vector distribution coefficients trading off the navigation accuracy and the observability degree of each state component are computed to replace the traditional scalar coefficients. Second, a fault-tolerant filter is proposed as the local navigation filter.

Simulations for the navigation of a UAV system show that the proposed method can be applied for accurate navigation purpose even in the presence of subsystem navigation faults.

New fault-tolerant federated Kalman filters for integrated navigation are presented to achieve accurate navigation solutions.

The aim of the paper is to shed light on the use of chitosans and chitooligosaccharides as biopreservatives in various foods animal. Foods of animal and aquatic origin (milk, meat, fish, eggs, sea foods, etc) become contaminated with a wide range of microorganisms (bacteria, molds and yeasts) during harvesting, transporting, processing, handling and storage operations. Due to the perishable nature of these foods, their preservation is of utmost importance. Though many synthetic chemicals are available, yet their use is quite restricted due to their hazardous effects on human health.

Within the domain of food industry, traditionally chitosan is used for biopreservation of foods, which is well known for its nutritional and medicinal properties in human nutrition. However, chitooligosaccharides also possess a number of nutraceutical and health promoting properties in addition to their preservative effect and shelf-life extension of foods. In this study, the comparative effects of both chitosan and chitooligosaccharides on preservation of foods of animal and aquatic origin have been summarized.

Though chitosan has been extensively studied in various foods, yet the use of chitooligosaccharides has been relatively less explored. Chitooligosaccharides are bioactive molecules generated from chitosan and have several advantages over the traditional use of chitosan both in food products and on human health. But unfortunately, little or no literature is available on the use of chitooligosaccharides for preservation of some of the foods of animal origin. Notable examples in this category include cheese, beef, pork, chicken, fish, sea foods, etc.

This paper focuses on the effects of chitosans and chitooligosaccharides on the processing and storage quality of foods of animal and aquatic origin, which offers a promising future for the development of functional foods.

This paper aims to examine how banks’ accounting disclosure policies affect information content in stock prices and stock crash risk.

This paper uses 1996-2013 as the sample period. The final sample includes 10,045 observations in 37 countries. This paper uses stock return synchronicity to measure information content in stock prices. This study uses the frequency difference between extremely negative and positive stock returns to measure stock crash risk. To measure the level of bank accounting disclosure, this research follows Nier and Baumann (2006) to construct an aggregate disclosure index based on inclusions and omissions of a series of items in a bank’s annual accounting reports.

This paper finds that banks’ stocks have lower stock return synchronicity and fewer extremely negative returns if banks have higher levels of financial statement disclosure. These results suggest that banks’ stocks have higher information content and lower crash risk if banks’ information environment is more transparent.

Overall, this paper provides new insight about how to increase banks’ transparency and the safety of the banking industry, which is beneficial to economic growth. To increase banks’ transparency and reduce the possibility of extremely negative stock returns, one way to regulate banks is to increase their accounting disclosure. In addition, the extant literature (Chen et al., 2006, Durnev et al., 2003, 2004; Wurgler, 2000) demonstrates that firms with lower stock return synchronicity have more transparent information environments and higher investment efficiency. Thus, this paper finds that higher levels of bank accounting disclosure are associated with lower stock return synchronicity, which further reduces banks’ opacity and increases banks’ investment efficiency. Finally, compared to business firms, stock crash risk has much direr consequences because one bank’s stock crash will affect overall financial stability. Thus, it is important for authorities to know the effects of accounting disclosure on bank stock crash risk.

Physical contact and traditional sensitive structure Physical contact and traditional pressure-sensitive structures typically do not operate well in harsh environments. This paper proposes a high-temperature pressure measurement system for wireless passive pressure sensors on the basis of inductively coupled LC resonant circuits.

This paper begins with a general introduction to the high-temperature pressure measurement system, which consists of a reader antenna inductively coupled to the sensor circuit, a readout unit and a heat insulation unit. The design and fabrication of the proposed measurement system are then described in detail.

A wireless passive pressure sensor without an air channel is fabricated using high-temperature co-fired ceramics (HTCC) technology and its signal is measured by the designed measurement system. The designed heat insulation unit keeps the reader antenna in a safe environment of 159.5°C when the passive sensor is located in a 900°C high-temperature zone continuously for 0.5 h. The proposed system can effectively detect the sensor’s resonance frequency variation in a high bandwidth from 1 to 100 MHz with a frequency resolution of 0.006 MHz, tested from room temperature to 500°C for 30 min.

Expensive and bulky equipment (impedance analyzers or network analyzers) restrict the use of the readout method outside the laboratory environment. This paper shows that a novel readout circuit can replace the laboratory equipment to demodulate the measured pressure by extracting the various sensors’ resonant frequency. The proposed measurement system realizes automatic and continuous pressure monitoring in a high-temperature environment with a coupled distance of 2.5 cm. The research finding is meaningful for the measurement of passive pressure sensors under a wide temperature range.

The purpose of this paper is to investigate the pose control of rigid spacecraft subject to dead-zone input, unknown external disturbance and parametric uncertainty in space maneuvering mission.

First, a 6-Degree of Freedom (DOF) dynamic model of rigid spacecraft with dead-zone input, unknown external disturbances and parametric uncertainty is derived. Second, a super-twisting-like fixed-time disturbance observer (FTDO) with strong robustness is developed to estimate the lumped disturbances in fixed time. Based on the proposed observer, a non-singular fixed-time terminal sliding-mode (NFTSM) controller with superior performance is proposed.

Different from the existing sliding-mode controllers, the proposed control scheme can directly avoid the singularity in the controller design and speed up the convergence rate with improved control accuracy. Moreover, no prior knowledge of lumped disturbances’ upper bound and its first derivatives is required. The fixed-time stability of the entire closed-loop system is rigorously proved in the Lyapunov framework. Finally, the effectiveness and superiority of the proposed control scheme are proved by comparison with existing approaches.

The proposed NFTSM controller can merely be applied to a specific type of spacecrafts, as the relevant system states should be measurable.

A NFTSM controller based on a super-twisting-like FTDO can efficiently deal with dead-zone input, unknown external disturbance and parametric uncertainty for spacecraft pose control.

This investigation uses NFTSM control and super-twisting-like FTDO to achieve spacecraft pose control subject to dead-zone input, unknown external disturbance and parametric uncertainty.

This chapter elaborates the peculiarities for the formation of the circular economy, substantiates its current contribution and future potential as to economic growth, and elaborates the concept and the implementation of the circular economy in Russia. Russian projects in the sphere of sustainable development and “ecologization” (reduction in energy, resource consumption, and polluting emissions) of industrial productions, mitigation, and processing of waste, protection of water resources, and restoration of forests are built into the linear model of production. The performed calculations on the basis of the existing statistical data allow evaluating the scale of the circular economy in Russia at $ 755.05 billion (as GDP in current market prices is 30.97% provided by the volume of used and decontaminated waste of production and consumption). In future, it is highly probable that the scale of the circular economy in Russia will reach 50% of GDP – $ 950.95 billion (as of 2018). To accelerate the rate and quality of economic growth, positive results from the implementation of these projects must be achieved. Complete transition to the model of the circular economy can provide new possibilities for long-term growth and the development of the Russian economy.

The purpose of this paper is to present findings from an initial year of mentoring and induction provided to new assistant principals (APs) served by the Kansas Educational Leadership Institute (KELI) and to identify program characteristics that support leadership development for first year APs.

The current research utilized surveys and interviews for data collection. The participants included 12 new AP mentees and five mentors currently participating in the KELI program. Two comparable questionnaires are designed to examine perceptions of both groups on the effectiveness of the program in general, mentoring/induction approaches used, and the appropriateness of the intensity of engagement required. The semi-structured interviews provide contextualized understanding of the same aspects examined in the surveys.

The findings reveal that mentees found mentoring/induction experiences with KELI highly valuable. The mentor-mentee matching mechanism together with other structured components in the KELI program such as mentor coaching training and multiple professional learning opportunities was instrumental for promoting a trustful relationship, reciprocal learning, and personalized and growth-based assistance that are key to successful mentoring/induction experiences.

The study findings will inform the research-based requirements in KELI’s model and further define effective components in serving the unique and varied responsibilities inherent in the AP position.

There is a need to identify elements in effective mentoring and induction support for new APs and to encapsulate best practices to further develop skills and dispositions for this important leadership position.