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Forecasts of commodity prices are vital issues to market participants and policy makers. Those of corn are of no exception, considering its strategic importance. In the present study, the authors assess the forecast problem for the weekly wholesale price index of yellow corn in China during January 1, 2010–January 10, 2020 period.

The authors employ the nonlinear auto-regressive neural network as the forecast tool and evaluate forecast performance of different model settings over algorithms, delays, hidden neurons and data splitting ratios in arriving at the final model.

The final model is relatively simple and leads to accurate and stable results. Particularly, it generates relative root mean square errors of 1.05%, 1.08% and 1.03% for training, validation and testing, respectively.

Through the analysis, the study shows usefulness of the neural network technique for commodity price forecasts. The results might serve as technical forecasts on a standalone basis or be combined with other fundamental forecasts for perspectives of price trends and corresponding policy analysis.

The purpose of this paper is to measure the apparent and complex viscosities of the zinc‐rich coatings derived from sodium silicate solution modified with aluminium chloride (AlCl₃), and then theoretically analyse the relation between viscosity behaviour and physiochemical mechanisms.

According to the different dosages of AlCl₃, five coatings were prepared. The apparent viscosities as functions of shear rate, time and temperature, complex viscosity with variations of temperature and heating rate of these coatings were measured using an AR500 rheometer.

Results showed that the zinc‐rich coatings possessed the typical shear thinning behaviour and the apparent viscosity increased with time until solidification. Complex results showed that the complex viscosity depended strongly on heating rate. Both apparent and complex viscosities initially decreased to minimum and then started to increase, while temperature was ramped from 0 to 70°C.

It is believed that there is no published literature about the apparent and complex viscosities of the zinc‐rich coatings from sodium silicate solution modified with AlCl₃. This paper presents the first attempt to obtain the rheological data of these zinc‐rich coatings.

The purpose of this paper is to reveal the dynamic contact characteristics of the slip ring. Dynamic contact resistance models considering wear and self-excited were established based on fractal theory.

The effects of tangential velocity, stiffness and damping coefficient on dynamic contact resistance are studied. The relationships between fractal parameters, wear time and contact parameters are revealed.

The results show that the total contact area decreases with the friction coefficient and fractal roughness under the same load. Self-excited vibration occurs at a low speed (less than 0.6 m/s). It transforms from stick-slip motion at 0.4 m/s to pure sliding at 0.5 m/s. A high stiffness makes contact resistance fluctuate violently, while increasing the damping coefficient can suppress the self-excited vibration and reduce the dynamic contact resistance. The fractal contact resistance model considering wear is established based on the fractal parameters models. The validity of the model is verified by the wear tests.

The results have a great significance to study the electrical contact behavior of conductive slip ring.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2023-0300/

The purpose of this study is to reveal the mechanism of peer abusive supervision on bystander behavior based on the perspective of bystander from two different paths of bystander empathy and bystander hostility toward supervisor. At the same time, it discusses the moderation effect of bystander traditionality on the two paths.

This study conducted a three-wave longitudinal survey. The data were collected from 454 employees and their coworkers in several Chinese enterprises. The authors used Mplus 7.4 and adopted a bootstrapping technique in the data analysis.

Peer abusive supervision leads bystanders to empathize with the abused colleague and thus exhibit more organizational citizenship behaviors, and peer abusive supervision also induces bystanders to develop hostility toward the abusive supervisor and thus produce more workplace negative gossip behaviors. In addition, it is found that bystander traditionality has a moderation effect in the process by which peer perceptions of abusive supervision influence bystander empathy and bystander hostility.

Based on Affective Events Theory, this study explores the mechanism of colleague perception of abusive supervision on bystander behavior from a bystander perspective. The results of this study not only provide a more comprehensive expansion of the weighting factors in the influence mechanism of abusive supervision but also provide new ideas for organizations to reduce the negative effects of workplace abusive behaviors.

This paper aims to propose the mechanism of cross-network effect embedded, which can help cross-border e-commerce (CBEC) platforms strengthen cooperative relationships with sellers more equitably and effectively by using the network structural characteristics of the platforms themselves.

A two-stage evolutionary game model has been used to confirm the influence factors. The mathematical derivation of evolutionary game analysis is combined with the simulation method to examine the role of cross-network effect in cooperation. The evolutionary game model based on the cross-network effect is proposed to achieve better adaptability to the study of cooperation strategy from the two-sided market perspective.

The evolutionary game model captures the interactions of cross-network effect and the influence factors from a dynamic perspective. The cross-network effect has a certain substitution on the revenue-sharing rate of SMEs. CBEC platforms can enhance the connection between consumers and the website by improving the level of construction, which is a good way to attract sellers more cost-effectively and efficiently.

This study provides a new method for the validation of the cross-network effect, especially when data collection is difficult. But this method is only a numerical simulation. So the conclusions still need to be further tested empirically. Besides, researchers are advised to explore the relationship between the added user scale and the cross-network effect in some specificCBEC platforms.

This study provides a new method for the validation of the cross-network effect, especially when data collection is difficult. But this method is only a numerical simulation. So the conclusions still need to be further tested empirically. Besides, researchers are advised to explore the relationship between the added user scale and the cross-network effect in some specific CBEC platforms.

Investigations that study cooperation strategy from the cross-network effect perspective in CBEC are limited. The research figured out which influence factors are affected by the cross-network effect in cooperation. A two-stage evolutionary game model was proposed to explain the interaction of the factors. The evolutionary game analysis with a simulation method was combined to highlight the role of cross-network effect on cooperation strategy to give a deeper investigation into the sustainable cooperation ofCBEC.

The purpose of this study is to ensure the safe use of carbon fiber composite pressure vessels in the nuclear industry environment.

This study investigated the degradation behaviors of carbon fiber reinforced composite (CFRP) using the specific corrosive media HF solution, with a focus on the damage to the surface epoxy layer. The degradation behaviors of CFRP in HF solution were examined by electrochemical methods and surface characterization, using HCl, NaCl and NaF solution for comparison.

The results showed that the specimen in HF solution will have a value of |Z|_0.01 Hz one order of magnitude lower, a substantially lower contact angle, more breakage of the surface epoxy and the stronger O─H peak and weaker C─O─C peak in the Fourier transform infrared spectrum, indicating severe hydrolytic damage to the surface epoxy.

The work focuses on the degradation damage to CFRP surface epoxy by specific corrosive media HF.

With the vigorous development of the e-commerce delivery service industry, delivery service has become an important factor for e-tailers to obtain the market competitive advantage. However, how to choose the best delivery service strategy is a difficult problem for e-tailers in practice. The purpose of this paper is to investigate the effect of delivery service on e-tailers and online platforms.

Based on the Stackelberg game, the research study establishes and solves three models, namely dual self-supporting delivery service model, dual third-party delivery service model and differential delivery service model.

The results show that when the self-supporting and third-party delivery cost coefficients are all small, no matter which delivery service providers the competitor selects, the e-tailer selects delivery with a lower service fee. When the self-supporting and third-party delivery service fee are all low, no matter which delivery service providers the competitor selects, the e-tailer selects delivery with a smaller service cost. Both service fee and service cost determine the choice of e-tailers' delivery strategy. When the commission rate is moderate, both e-tailers are willing to choose the self-supporting delivery strategy, but the platform only prefers to provide self-supporting delivery to them with a lower delivery service sensitivity coefficient.

This paper analyzes the optimal delivery service strategies for e-tailers to compete with competitors, and explores the impacts of parameters for e-tailers and online platforms in their decision-making. The findings provide valuable implications for relevant practices.

The recent surge in behavioral studies on the coordination mechanisms in supply chains (SCs) and advanced methods highlights the role of SC coordination (SCC) and behavioral issues associated with improving the performance of the operations. This study aims to critically review the behavioral aspect of channel coordination mechanisms.

Following a systematic literature review methodology, the authors adopt a combination of bibliometric (to reflect the current state of the field), content (using Leximancer data mining software to develop thematic maps) and theory-oriented qualitative analyzes that provide a holistic conceptual framework to unify the literature’s critical concepts.

The analysis confirms the plethora of risk-oriented publications, demonstrating that the second largest category of studies is concerned with social preferences theory. Most studies were based on experiments, followed by analytical modeling, revealing the impact of heuristics and individual preferences in SC decisions and suggesting promising managerial and theoretical avenues for future research.

The study sheds light on behavioral decision theories applied to SC coordination by categorizing the literature based on the adopted theories. The methodological contributions include using automated content analysis and validating the outcome by interviewing leading scholars conducting active research on “behavioral operations management and SC contracts.” The authors also propose several directions for future research based on the research gaps.

This study aims to discover whether COVID-19 phobia has a positive and significant effect on the stress, depression and anxiety levels of industrial consumers in addition to reveal whether environmental awareness plays a mediating role between COVID-19 phobia and stress, depression and anxiety.

In this study, a quantitative method was used to reveal the role of anxiety, depression and stress (psychological effects) and environmental awareness caused by covid-19 phobia on industrial consumers. The universe of the study is small and medium-sized enterprises operating in the province of Sanliurfa, which is located in the southeast region of Turkey and the second largest city in the region, and are industrial customers. Questionnaire method was used in the study. In addition, data were collected from 406 people who agreed to participate in the study. In the study, in which intermediary and regulatory analyzes were made, the process macro program was used.

The results show that there is a medium relationship between COVID-19 phobia and environmental awareness; and COVID-19 phobia and stress, depression and anxiety. No relationship was found between environmental awareness and stress, depression and anxiety. COVID-19 phobia was found to have a positive and significant effect on environmental awareness and stress, depression and anxiety, while environmental awareness was found to have no effect on stress, depression and anxiety. Finally, environmental awareness was found to play a mediating role between COVID-19 phobia and stress, depression and anxiety.

In this study, four hypotheses were developed. Of these hypotheses, three are for the simple effect and one for the mediation effect. Out of four hypotheses, three were supported. The most important inference obtained from the study was finding the mediation effect of environmental awareness between COVID-19 phobia and anxiety, depression and stress.

To the best of the authors’ knowledge, no studies in the literature were made on the relationship among COVID-19 phobia, environmental awareness, stress, depression and anxiety. This study also examines the mediating effect of environmental awareness in the relationship between COVID-19 phobia and stress, depression and anxiety. The fact that the study is on the negative effects of the pandemic on one of the most affected occupational group also increases its original value.

This study aims to present two stage pseudomorphic high electron mobility transistor-based low noise amplifier (LNA) designed using low temperature co-fire ceramic (LTCC) technique for ultra-high frequency (UHF) band. The LNA operates in the frequency range of (400∼500) MHz which is suitable for wireless communication applications.

This LNA uses resistive capacitive (RC) feedback in the first stage to have wide bandwidth and interstage network for gain enhancement. By using external RC feedback, stability is improved and noise matching in the input stage is isolated by decoupling inductor. The excellent performance parameters including gain, noise figure (NF), wideband and linearity are attained without affecting the power consumption, compactness and cost of the proposed design.

Simulation is carried out using advanced design software and the result shows that gain of 33.7 dB, NF 0.416 dB and 1 dB compression point (P_1dB) of 18.59 dBm are achieved with a supply voltage of 2.5 V. The return loss of input and output are −19.3 dB and −10.5 dB, respectively. From the above aforementioned parameters, it is confirmed that the proposed LNA is a promising candidate for receivers where high gain and very low NF are always demandable with good linearity for applications operating in the UHF band.

The innovation of the proposed LNA is that the concurrent attainment of high gain, low NF, wideband, optimum input matching, good stability by RC feedback and interstage network using LTCC technique to achieve robustness, low cost and compactness to prove the applicability of design for wireless applications.