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The purpose of this paper is to focus on the removal of hexavalent chromium [Cr(VI)] from wastewater by using activated carbon-supported Fe catalysts derived from walnut shell prepared using a wetness impregnation process. The different conditions of preparation such as impregnation rate and calcination conditions (temperature and time) were optimized to determine their effects on the catalyst’s characteristics.

The catalyst samples were characterized using thermogravimetric analysis, scanning electron microscopy and Fourier transform infrared spectroscopy. The adsorption of Cr(VI) by using using activated carbon supported Fe catalysts derived from walnut shell as an adsorbent and catalyst was investigated under different adsorption conditions. The parameters studied were contact time, adsorbent dose, solution pH and initial concentrations.

Results showed that higher adsorption capacity and rapid kinetics were obtained when the activated walnut shell was impregnated with Fe at 5 per cent and calcined under N₂ flow at 400°C for 2 h. The adsorption isotherms data were analyzed with Langmuir and Freundlich models. The better fit is obtained with the Langmuir model with a maximum adsorption capacity of 29.67 mg/g for Cr(VI) on Fe5-AWS at pH 2.0.

A comparison of two kinetic models shows that the adsorption isotherms system is better described by the pseudo-first-order kinetic model.

Many entrepreneurs are able to manage their businesses within relatively contained and familiar geographical and cultural circles. With a world economy shrinking every day amid a flood of digital information, todayʼs entrepreneur is increasingly confronted with opportunities to consider new ways to secure vendors and recruit customers. Many unfamiliar possibilities emerge. Should the entrepreneur venture beyond “comfortable” surroundings to consider international connections? Specifically, what about China? How practical is this fetching business temptation of larger markets and lower-cost subcontractors? What are the social, trade, financial, and political issues? Should a “China strategy” be a true entrepreneurial offensive, or rather a defensive response to competition? Is this “China strategy” the promise of yet another entrepreneurial nirvana? Or is it perhaps again a case of “Be careful of what you wish for; it may really come true?”

Efficient traffic incident management is needed to alleviate the negative impact of traffic incidents. Accurate and reliable estimation of traffic incident duration is of great importance for traffic incident management. Previous studies have proposed models for traffic incident duration prediction; however, most of these studies focus on the total duration and could not update prediction results in real-time. From a traveler’s perspective, the relevant factor is the residual duration of the impact of the traffic incident. Besides, few (if any) studies have used dynamic traffic flow parameters in the prediction models. This paper aims to propose a framework to fill these gaps.

This paper proposes a framework based on the multi-layer perception (MLP) and long short-term memory (LSTM) model. The proposed methodology integrates traffic incident-related factors and real-time traffic flow parameters to predict the residual traffic incident duration. To validate the effectiveness of the framework, traffic incident data and traffic flow data from Shanghai Zhonghuan Expressway are used for modeling training and testing.

Results show that the model with 30-min time window and taking both traffic volume and speed as inputs performed best. The area under the curve values exceed 0.85 and the prediction accuracies exceed 0.75. These indicators demonstrated that the model is appropriate for this study context. The model provides new insights into traffic incident duration prediction.

The incident samples applied by this study might not be enough and the variables are not abundant. The number of injuries and casualties, more detailed description of the incident location and other variables are expected to be used to characterize the traffic incident comprehensively. The framework needs to be further validated through a sufficiently large number of variables and locations.

The framework can help reduce the impacts of incidents on the safety of efficiency of road traffic once implemented in intelligent transport system and traffic management systems in future practical applications.

This study uses two artificial neural network methods, MLP and LSTM, to establish a framework aiming at providing accurate and time-efficient information on traffic incident duration in the future for transportation operators and travelers. This study will contribute to the deployment of emergency management and urban traffic navigation planning.

Research on grey systems is becoming more sophisticated, and grey relational and prediction analyses are receiving close review worldwide. Particularly, the application of grey systems in marine economics is gaining importance. The purpose of this paper is to summarize and review literature on grey models, providing new directions in their application in the marine economy.

This paper organized seminal studies on grey systems published by Chinese core journal database – CNKI, Web of Science and Elsevier from 1982 to 2018. After searching the aforementioned database for the said duration, the authors used the CiteSpace visualization tools to analyze them.

The authors sorted the studies according to their countries/regions, institutions, keywords and categories using the CiteSpace tool; analyzed current research characteristics on grey models; and discussed their possible applications in marine businesses, economy, scientific research and education, marine environment and disasters. Finally, the authors pointed out the development trend of grey models.

Although researches are combining grey theory with fractals, neural networks, fuzzy theory and other methods, the applications, in terms of scope, have still not met the demand. With the increasingly in-depth research in marine economics and management, international marine economic research has entered a new period of development. Grey theory will certainly attract scholars’ attention, and its role in marine economy and management will gain considerable significance.

In today's global business environment, international assignments have become integral part of employee's job profile. Adaptation to a different cultural environment plays a role in affecting employee's performance. In such a situation, cultural intelligence plays an important role. In order to sustain in a diverse work setting, a global organization entails managers who are sensitive to different cultural requirements. Factors affecting cultural intelligence have been a major area of study. However, studies relating short-term foreign trips and their role on four aspect of cultural intelligence are lacking. Therefore, present study was undertaken to know role of foreign visits in affecting cultural intelligence among professionals of diverse background.

The present study is a primary study conducted for a sample of 120 respondents divided into two groups. One group comprised professionals having experience of foreign visits while other group comprised professionals who had not visited a foreign country. We use Levene’s Test for equality of variances was applied to assess the difference of variation of cultural intelligence between two different groups of respondents.

The results revealed that short-term trips play a significant role in affecting metacognitive, cognitive and motivational components of cultural intelligence. However, behavior cultural intelligence is not affected by short-term trips significantly.

Outcome of present research forms basis for future studies that can be conducted linking long-term trips and culture intelligence. This study is practically useful for improving cultural intelligence of professionals to enhance their success and effectiveness in international assignments.

The study adds novelty to the field of cultural intelligence as prior studies were lacking in relating role of short-term trips on four different components of cultural intelligence.