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Entrepreneurial process strongly relies on context. The previous entrepreneurship research in developed countries over-emphasizes on its economic impact, but ignores its social impact, which leads to the slow development of entrepreneurship theories. Transitioning China provides entrepreneurs with a typical environment where opportunities and constraints coexist, which is a new research area in the field of entrepreneurship study.

Based on the grounded theory approach, this paper generalizes a local entrepreneurial process model from a multiple case study.

The paper states that the interaction among entrepreneurs, opportunities and institutional context is the core of the process. To be specific, entrepreneurial process includes an inner and an outer mechanism. The inner mechanism is based on the relations among institutional constraints, entrepreneurs and opportunities: nascent entrepreneurs, forced by institutional constraints to start a business, undergo a psychological process with entrepreneurial angst, reflective learning and effectuation and finally create business opportunities. The outer mechanism is grounded in the relations among new ventures, institutional evolution and opportunity development: new ventures facilitate institutional evolution through institutional entrepreneurship strategies, which in turn supports the ventures in the sustainable development of opportunities.

This study illuminates the social and institutional impact of entrepreneurial behavior, which is gradually fading and forgotten in modern society. The findings of the study enrich the research on entrepreneurial process, entrepreneurial cognition and institutional entrepreneurship and also provide implications for entrepreneurs.

In this study, an eco-friendly cotton fabric (CF) treatment method was proposed to induce anti-ultraviolet and flame retardant properties, and a new application of tannic acid (TA) and phytic acid (PA) in ultraviolet protection and flame retardant fabric was put forward.

By combining diethylenetriamine, PA and TA on CF, a chemical reaction intumescent flame retardant CF with anti-ultraviolet and anti-flame retardance was developed.

The flame retardant and ultraviolet resistance of CF were characterized by LOI, vertical combustion, cone calorimetry and ultraviolet resistance testing. SEM, XPS, FTIR and other tests were used to analyze the chemical composition, surface morphology and residual carbon after combustion of the CF, and it was confirmed that the modified CF has good ultraviolet resistance and flame retardant performance.

In this study, an eco-friendly CF treatment method was proposed to induce anti-ultraviolet and flame retardant properties, and a new application of TA and PA in ultraviolet protection and flame retardant fabric was put forward.

The purpose of the paper is to investigate how cross-cultural elements such as cultural difference and stereotype are integrated into collaborative modes and actions and to explore their corresponding effectiveness.

The sample of the quantitative content analysis is drawn from the posts with the topic of China on Quora. A collaborative case, where two users have a question-and-answer interaction, is taken as the unit of analysis. The effectiveness of collaboration is operationalized as the extent to which a collaboratively produced answer is visited and favorably reviewed, using the feedback index (the number of upvotes*1,000/views). One of the sampled collaborative cases is further analyzed qualitatively to see how cultural differences, stereotypes and other factors are incorporated into users' interaction.

This content analysis reveals nine modes of collaborative production of knowledge on Quora: initial questioning, pointed answering, raising doubts, responding to others, agreeing with others, correcting mistakes, enriching content, further questioning and extending issues. Diversity of the cross-cultural acts of collaborative production, particularly two of often-used collaborative actions, correcting stereotypes and supplementing cultural differences, helps to enhance overall collaborative effectiveness.

This paper offers new perspectives and ideas for strategies to change socially problematic stereotypes, e.g. to correct stereotypes where necessary and use more convincing resources such as reliable images as collaborative actions to bridge cultural differences. It also calls on social Q&A website developers to create more international users-friendly design by providing various channels for users with diverse cultural backgrounds to interact with each other.

This study is one of the first to investigate online collaborative knowledge production within a broader cross-cultural context. Specifically, cultural factors and cross-cultural collaborative actions have been innovatively integrated into this research, enriching the dimensions that can be used for collaboration classification. It is helpful for users from different countries to actively adopting different strategies to overcome cultural differences, preconceptions and other negative factors that are not conducive to communication and knowledge acquisition.

The purpose of this paper is to introduce an innovative theoretical, numerical and experimental investigations on the HP NGD function. The identified HP NGD topology under study is constituted by first order passive RC-network. The simulations and measurements confirm in very good agreement the HP NGD behaviors of the tested circuits. NGD responses with optimal values of about -1 ns and cut-off frequencies of about 20 MHz are obtained.

The identified HP NGD topology understudy is constituted by a first-order passive Resistor-capacitor RC network. An innovative approach to HP NGD analysis is developed. The analytical investigation from the voltage transfer function showing the meaning of HP properties is established.

This paper introduces innovative theoretical, numerical and experimental investigations on the HP NGD function.

The NGD characterization as a function of the resistance and capacitance parameters is investigated. The feasibility of the HP NGD function is verified with proofs of concept constituted of lumped surface mounted components on printed circuit boards. The simulations and measurements confirm in very good agreement the HP NGD behaviors of the tested circuits. NGD responses with optimal values of about −1 ns and cut-off frequencies of about 20 MHz are obtained.

This paper aims to explore the influence of CO₂ partial pressure, flow rate and water cut on N80 steel corrosion behaviors in the displacement process of oil in glutenite reservoir by CO₂ injection.

A self-made 3 L high-temperature and high-pressure autoclave was used to conduct corrosion simulation experiments of N80 steel in different CO₂ partial pressures, flow rates and water cut (the independently developed oil and water mixing approach can ensure the uniform mixing of oil and water in experiments). Techniques like weight loss and surface analysis were used to analyze the corrosion behaviors of N80 steel under different conditions.

Results showed that the average corrosion rate of N80 steel accelerated at varying degrees with the increase of CO₂ partial pressure, flow rate and water cut. Excluding that the samples showed uniform corrosion under the two conditions of 0.5MPa CO₂ partial pressure and static corrosion, they displayed mesa attack corrosion under other conditions. Besides, with the increase of CO₂ partial pressure, the pH value of solution dropped and the matrix corrosion speed rose, hence leading to the increased Fe²⁺ and CO₃²⁻ concentration. Meanwhile, a lowered pH value improved the FeCO₃ critical supersaturation, thereby leading to an increased nucleation rate/growth rate and ultimately causing the decrease of the dimension of FeCO₃ crystallites formed on the surface of the samples.

The results can be helpful in targeted anti-corrosion measures for CO₂/oil/water corrosive environment.

In the event of a DC short-circuit fault in a flexible DC power grid, the high peak value of the fault current puts forward more stringent requirements on the DC circuit breaker. The existing fault current cutoff mainly focuses on changing the topology structure. To suppress the development of fault current and reduce the investment cost of the DC grid, this paper aims to propose a dual-loop active current-limiting control based on energy difference.

Firstly, the equivalent circuit at fault is established, and the parameters related to the fault current are analyzed. Then, the relationship between the output voltage change of the bridge arm and the difference between the AC and DC energy is deduced. Finally, the experimental results are discussed on the real-time simulation platform Opal-RT.

The proposed current-limiting measures can greatly reduce the fault current, reduce the breaking current of the circuit breaker and increase the capacitor voltage during the fault period, which is beneficial to the stability of the AC system. It is verified that the proposed method is also applicable to a certain high-resistance fault.

This paper applies the method of AC fault to DC fault and deduces the relationship between energy difference and voltage variation corresponding to different step lengths based on digital simulation. In addition, two variables are used as control structure parameters to reduce the probability of system misoperation.

In the last a few years a number of highly publicized incidents of Distributed Denial of Service (DDoS) attacks against high‐profile government and commercial websites have made people aware of the importance of providing data and services security to users. A DDoS attack is an availability attack, which is characterized by an explicit attempt from an attacker to prevent legitimate users of a service from using the desired resources. This paper introduces the vulnerability of web applications to DDoS attacks, and presents an active distributed defense system that has a deployment mixture of sub‐systems to protect web applications from DDoS attacks. According to the simulation experiments, this system is effective in that it is able to defend web applications against attacks. It can avoid overall network congestion and provide more resources to legitimate web users.

The tribological behavior, i.e. friction coefficient and wear rate, and vibration characteristics of the water-lubricated bearing was investigated. The water-lubricated bearing is made of three different materials, i.e. polyether-ether-ketone (PEEK), polyimide (PI) and nitrile-butadiene rubber (NBR).

The tribological behavior was investigated experimentally on a specially designed test rig. Three vibration sensors were used to record the vibration of the bearing.

The results indicated that the variation of friction coefficient with rotation speed agrees well with the trend of Stribeck curve. The tested friction coefficient of rubber bearing is higher than that of the other two bearings whether it is in the state of mixed-lubrication or hydrodynamic lubrication, and which causing a larger wear rate in rubber bearing. The PEEK bearing exhibits the best tribological properties due to it has smaller friction coefficient and wear rate. However, it can be found that the rubber bearing gives the minimum vibration acceleration, which means that the rubber bearing has the most potential to improve the stability of water-lubricated bearing rotor system.

In this study, a group of experiment studies conducted on a specially designed test rig. The comprehensive performance, including friction coefficient, vibration acceleration and wear rate, of water-lubricated bearing with three different materials, i.e. PEEK, PI and NBR, was compared systematically. The experiment research may offer a reference for the selection of material in water-lubricated bearing in specific operating conditions.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2019-0447/

Indoor localization is a key tool for robot navigation in indoor environments. Traditionally, robot navigation depends on one sensor to perform autonomous localization. This paper aims to enhance the navigation performance of mobile robots, a multiple data fusion (MDF) method is proposed for indoor environments.

Here, multiple sensor data i.e. collected information of inertial measurement unit, odometer and laser radar, are used. Then, an extended Kalman filter (EKF) is used to incorporate these multiple data and the mobile robot can perform autonomous localization according to the proposed EKF-based MDF method in complex indoor environments.

The proposed method has experimentally been verified in the different indoor environments, i.e. office, passageway and exhibition hall. Experimental results show that the EKF-based MDF method can achieve the best localization performance and robustness in the process of navigation.

Indoor localization precision is mostly related to the collected data from multiple sensors. The proposed method can incorporate these collected data reasonably and can guide the mobile robot to perform autonomous navigation (AN) in indoor environments. Therefore, the output of this paper would be used for AN in complex and unknown indoor environments.

The purpose of this paper is to introduce a wireless web‐based ordering system called iMenu in the restaurant industry.

By using wireless devices such as personal digital assistants and WebPads, this system realizes the paradigm of pervasive computing at tableside. Detailed system requirements, design, implementation and evaluation of iMenu are presented.

The evaluation of iMenu shows it explicitly increases productivity of restaurant staff. It also has other desirable features such as integration, interoperation and scalability. Compared to traditional restaurant ordering process, by using this system customers get faster and better services, restaurant staff cooperate more efficiently with less working mistakes, and enterprise owners thus receive more business profits.

While many researchers have explored using wireless web‐based information systems in different industries, this paper presents a system that employs wireless multi‐tiered web‐based architecture to build pervasive computing systems. Instead of discussing theoretical issues on pervasive computing, we focus on practical issues of developing a real system, such as choosing of web‐based architecture, design of input methods in small screens, and response time in wireless web‐based systems.