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High-silicon cast iron has excellent corrosion resistance in some specific medium. But the effects of pH value, chloride concentration and soil moisture content on corrosion behavior are still unknown. This study aims to provide reference for the application of high-silicon cast iron in different environments.

Electrochemical impedance spectroscopy and potentiodynamic polarization curves were used to investigate the corrosion mechanism and rate. The morphology was observed by scanning electron microscopy. The chemical compositions of the corrosion products were detected by energy-dispersive spectroscopy and X-ray diffraction.

When the solution is acidic, the corrosion of high-silicon cast iron is more serious. When the chloride concentration is 0.1 per cent, the corrosion rate of high-silicon cast iron is the largest. A passive film is formed on the surface to prevent the corrosion reaction with the increasing of chloride concentration. The corrosion rate is the largest when water content is 15 per cent, and the corrosion is the lightest when water content is 30 per cent.

This study provides support for the selection of high-silicon cast iron as grounded material.

A consistent implementation of the general computational framework of unified second-order time accurate integrators via the well-known GSSSS framework in conjunction with the traditional Finite Difference Method is presented to improve the numerical simulations of reactive two-phase flows.

In the present paper, the phase interaction evaluation in the present implementation of the reactive two-phase flows has been derived and implemented to preserve the consistency of the correct time level evaluation during the time integration process for solving the two phase flow dynamics with reactions.

Numerical examples, including the classical Sod shock tube problem and a reactive two-phase flow problem, are exploited to validate the proposed time integration framework and families of algorithms consistently to second order in time accuracy; this is in contrast to the traditional practices which only seem to obtain first-order time accuracy because of the inconsistent time level implementation with respect to the interaction of two phases. The comparisons with the traditional implementation and the advantages of the proposed implementation are given in terms of the improved numerical accuracy in time. The proposed approaches provide a correct numerical simulation implementation to the reactive two-phase flows and can obtain better numerical stability and computational features.

The new algorithmic framework and the consistent time level evaluation extended with the GS4 family encompasses a multitude of past and new schemes and offers a general purpose and unified implementation for fluid dynamics.

In computational fluid dynamics for two-phase reactive flow of interior ballistic, the conventional schemes (MacCormack method, etc.) are known to introduce unphysical oscillations in the region where the gradient is high. This paper aims to improve the ability to capture the complex shock wave during the interior ballistic cycle.

A two-phase flow model is established to describe the complex physical process based on a modified two-fluid theory. The solution of model is obtained including the following key methods: an approximate Riemann solver to construct upwind fluxes, the MUSCL extension to achieve high-order accuracy, a splitting approach to solve source terms, a self-adapting method to expand the computational domain for projectile motion and a control volume conservation method for the moving boundary.

The paper is devoted to applying a high-resolution numerical method to simulate a transient two-phase reactive flow with moving boundary in guns. Several verification tests demonstrate the accuracy and reliability of this approach. Simulation of two-phase reaction flow with a projectile motion in a large-caliber gun shows an excellent agreement between numerical simulation and experimental measurements.

This paper has implications for improving the ability to capture the complex physics phenomena of two-phase flow during interior ballistic cycle and predict the combustion details, such as the flame spreading, the formation of pressure waves and so on.

This approach is reliable as a prediction tool for the understanding of the physical phenomenon and can therefore be used as an assessment tool for future interior ballistics studies.

Even the smartest organizations believe that “good enough is never good enough.” Highly intelligent people may be able to do important things individually; still, it is their accumulated brainpower that allows them to do great things. Collective intelligence means when a group of people do things that seem intelligent. On the other hand, when intelligent people are gathered or hired in an organization, they tend toward collective stupidity and slow-wittedness. Therefore, the purpose of the present study is to develop a model of the factors affecting and affected by collective stupidity.

This study was conducted using a mixed-method approach and in two phases: qualitative and quantitative. First, in the qualitative phase and in order to achieve new findings, semi-structured interviews with experts from 12 knowledge-based companies were used to design a conceptual model and formulate the hypotheses. At the end of the qualitative phase, the conceptual model and relationships between variables were drawn. Then, in the quantitative phase, by running structural equation modeling, the antecedents and consequences of collective stupidity derived from the qualitative phase findings were analyzed and the research hypotheses were tested in 110 industrial knowledge-based companies.

The results of the qualitative phase revealed that individual, group and organizational factors were the antecedents of collective stupidity, with individual factors having three dimensions, collective ones including two dimensions and organizational ones focusing on the characteristics of managers/companies. It was also found that collective stupidity had individual consequences in three dimensions and organizational consequences in five dimensions; and one-sidedness, non-strategic thinking, organizational injustice and weakness in the management of key personnel were extracted as mediators. The results of the quantitative phase confirmed the research model and showed that individual factors and organizational consequences had the lowest (0.037) and highest (1.084) effect sizes on collective stupidity, respectively.

The study of the phenomenon in a particular context and the difficulty of generalizing the findings to other situations, the small size of the study population due to the disproportionate number of experts to the total staff in the qualitative phase, and the limited participation of experts due to the negative nature of the issue in the quantitative phase. Taking advantage of the diversity of experts' mental abilities through equipping the organization with tools for recognizing collective stupidity, improving collective decision-making, enhancing the efficiency of think tanks and organizational prosperity in the age of knowledge economy, preventing damage to the body of knowledge of the company and reducing social loafing can be the main operational implications of this study.

Using a mixed-method approach for analyzing the antecedents and consequences of collective stupidity in this study and examining such a phenomenon in a knowledge-based organizational context and its implementation in a developing country can be among the innovations of the present research. By following a few studies conducted in this field in addition to the organizational pathology of the phenomenon using a fundamental method, this study obtained deep results on how to make the maximum use of experts’ capacities. This was to the extent that in all of the three sections, i.e. the antecedents and consequences of collective stupidity, a new factor emerged.

This paper seeks to explore the evolution of a third generation mobile communications (3G) industry based on TD‐SCDMA technical standard in China through the lens of network analysis.

The authors argue that inter‐firm alliances help companies gain and integrate internal and external resources and foster technical innovation. The paper analyzes alliance governance structures and governance mechanisms in particular, and shows how they protect and improve network‐based innovation capabilities and competitive advantages during a ten‐year period with the method of social network analysis and case studies.

The authors offer a theoretical model that incorporates cooperation among organizations, the maturity of the industrial chain, and the accumulation of organizational knowledge and social capital.

The paper offers a theoretical model of factors that contributes greatly to the development of technical innovation.

Prior research studies have discussed the role of corporate social responsibility (CSR) during crisis situations in increasing the resilience and sustainability of the companies. There are two basic models of crisis management – reactive and proactive. When a crisis occurs, suddenly firms tend to act reactively and progressively take proactive steps to manage the crisis. CSR can also be reactive and proactive during crisis situations. Against this backdrop, this paper aims to explore whether CSR during the COVID-19 pandemic moved from a reactive to a proactive stance, with specific focus on CSR legislation, corporate CSR response and corporate thinking about CSR.

This paper adopts a mixed methods approach, using both qualitative and quantitative research designs. This study draws upon both primary and secondary data.

The results highlighted the change in the CSR approach from being reactive to being proactive as the pandemic progressed. This was observed through the increase in frequency of CSR legislation, and the shift in the intent of CSR legislation from “prompting to donate” to “prompting to volunteer.” Similarly, the shift in reactive to proactive CSR corporate response was observed through the increased spending on CSR and improved COVID-related CSR reporting.

This study recommends companies to manage crises by becoming more proactive. CSR activities need to be closely aligned with national developmental objectives, and collaborate with various stakeholders to achieve the intended outcomes of the activities.

To the best of the authors’ knowledge, this research paper is one of the few to study the impact of COVID-19 pandemic on CSR in India at a time when India went through three waves of the pandemic. This study corroborates with other studies in terms of managing crisis.

The purpose of this paper is to show how intelligence techniques have been used in information management systems.

The results of a literature review on intelligence decision systems used in enterprise information management are analyzed. The intelligence techniques used in enterprise information management are briefly summarized.

Intelligence techniques are rapidly emerging as new tools in information management systems. Especially, intelligence techniques can be used to utilize the decision process of enterprises information management. These techniques can increase sensitiveness, flexibility and accuracy of information management systems. The hybrid systems that contain two or more intelligence techniques will be more used in the future.

The intelligence decision systems are briefly introduced and then a literature review is given to show how intelligence techniques have been used in information management systems.

The purpose of this paper is to introduce the elementary concepts and fundamental principles of grey systems and the main components of grey systems theory. Also to discuss the astonishing progress that grey systems theory has made in the world of learning and its wide‐ranging applications in the entire spectrum of science.

The characteristics of unascertained systems including incomplete information and inaccuracies in data are analysed and four uncertain theories: probability statistics, fuzzy mathematics, grey system and rough set theory are compared. The scientific principle of simplicity and how precise models suffer from inaccuracies are also shown.

The four uncertain theories, probability statistics, fuzzy mathematics, grey system and rough set theory are examined with different research objects, different basic sets, different methods and procedures, different data requirements, different emphasis, different objectives and different characteristics.

The scientific principle of simplicity and how precise models suffer from inaccuracies are shown. So, precise models are not necessarily an effective means to deal with complex matters, especially in the case that the available information is incomplete and the collected data inaccurate.

The elementary concepts and fundamental principles of grey systems and the main components of grey systems theory are introduced briefly. The reader is given a general picture of grey systems theory as a new method for studying problems where partial information is known, partial information is unknown; especially for uncertain systems with few data points and poor information.

The purpose of this paper is under the analysis framework of the system theory, analyzing the optimal contract mode of agricultural supply chain to guarantee the stability of agricultural supply chain and the equilibrium of agricultural product market, to analyze the effect of farmers’ risk attitude on the selection of contract modes and to find the way to encourage farmers’ productive effort and to avoid farmers’ hitchhiking behavior, to guarantee the stability of agricultural supply chain.

Under the guidance of the system theory, using the Stackelberg model and the nonlinear programming theory, this paper comparatively analyzes farmers’ effort (productive effort and sales effort), farmers’ income and the stability of agricultural supply system of four types of contract modes between farmers, third-party organizations and market.

First, in the agricultural market, market-type contract cannot maximize farmers’ income. The main reason is that farmers do not have enough ability to avoid market risk and to bargain. Second, for farmers of risk seeking, choosing a market-type contract and secondary-income contract can increase their income. Third, under the fixed-purchase price contract, the hitchhiking behavior would happen. Fourth, when farmers’ productive efforts are the same, farmers’ income under the secondary-income contract is higher than under the fixed-purchase price contract. Because under the secondary-income contract, farmers have the opportunity to obtain the secondary distribution of benefits, farmers’ hitchhiking behavior could be avoided.

Analyzing the contract modes between farmers and the third-party organization in the agricultural market could reduce the influence of price fluctuation, avoid the uncertainty of the relationship between the supply and demand, stimulate the productive effort of farmers and provide theoretical guidance for establishing efficient and stable agricultural supply system.

The purpose of this paper is to investigate the effect of different soldering temperatures on the performance of chip-on-board (COB) light sources during vacuum reflow soldering.

First, the influence of the void ratio of the COB light source on the steady-state voltage, luminous flux, luminous efficiency and junction temperature has been explored at soldering temperatures of 250°C, 260°C, 270°C, 280°C and 290°C. The COB chip has also been tested for practical application and aging.

The results show that when the soldering temperature is 270°C, the void ratio of the soldering layer is only 5.1%, the junction temperature of the chip is only 76.52°C, and the luminous flux and luminous efficiency are the highest, and it has been observed that the luminous efficiency and average junction temperature of the chip are 107 lm/W and 72.3°C, respectively, which meets the requirements of street lights. After aging for 1,080 h, the light attenuation is 84.64% of the initial value, which indicates that it has higher reliability and longer life.

It can provide reference data for readers and people in this field and can be directly applied to practical engineering.