• Journal of Microbiology and Biotechnology
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• v.30 no.7
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• pp.1005-1012
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• 2020

Acid mine drainage (AMD) has been a serious environmental issue that threatens soil and aquatic ecosystems. In this study, an acid-tolerant sulfate-reducing bacterium, strain S4, was isolated from the mud of an AMD storage pond in Vietnam via enrichment in anoxic mineral medium at pH 5. Comparative analyses of sequences of the 16S rRNA gene and dsrB gene involved in sulfate reduction revealed that the isolate belonged to the genus Desulfovibrio, and is most closely related to Desulfovibrio oxamicus (with 99% homology in 16S rDNA sequence and 98% homology in dsrB gene sequence). Denaturing gradient gel electrophoresis (DGGE) analyses of dsrB gene showed that strain S4 represented one of the two most abundant groups developed in the enrichment culture. Notably, strain S4 was capable of reducing sulfate in low pH environments (from 2 and above), and resistance to extremely high concentration of heavy metals (Fe 3,000 mg/l, Zn 100 mg/l, Cu 100 mg/l). In a batch incubation experiment in synthetic AMD with pH 3.5, strain S4 showed strong effects in facilitating growth of a neutrophilic, metal sensitive Desulfovibrio sp. strain SR4H, which was not capable of growing alone in such an environment. Thus, it is postulated that under extreme conditions such as an AMD environment, acid- and metal-tolerant sulfate-reducing bacteria (SRB)-like strain S4 would facilitate the growth of other widely distributed SRB by starting to reduce sulfate at low pH, thus increasing pH and lowering the metal concentration in the environment. Owing to such unique physiological characteristics, strain S4 shows great potential for application in sustainable remediation of AMD.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.2
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• pp.107-117
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• 2020

The research objective of the paper is to clarify the factors influencing system risks of listed companies in Vietnam, with a focus on clarifying the relationship and quantifying the impacts of ownership structure on systemic risk of listed companies. The data used in this study included financial statements and stock price data of listed companies on the Ho Chi Minh City Stock Exchange and Hanoi Stock Exchange of Vietnam stock market in the period from 2010 to 2017. The paper used the method of estimation in establising the regression models to choose among three models: Random Effect Model, Fixed Effect Model or Pooled OLS for regression using Stata statistical software. The research results showed that state ownership and ownership by foreign investors were positively related to systemic risk, while ownership by domestic investors had a reverse relationship with systemic risk of listed companies in Vietnam. In addition, as a control variable, both company size and profitability had an effect on the systemic risk of listed companies in the research sample. Based on the research results, the authors interpreted some of the implications in order to minimize systemic risks in the operation of listed companies in Vietnam.

• Journal of Navigation and Port Research
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• v.40 no.5
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• pp.305-310
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• 2016

The sea-port in Northern Vietnam accounts for around one third of the total country's cargo throughput and for many decades has been playing an important role in the logistics system of the country. 11 container terminals currently operate in Northern Vietnam, concentrating in Haiphong city and Quang Ninh province. Despite the increasing demand, the competition among these container terminals has become increasingly more critical. In recent years, massive investments from both government and operators have been made to improve the capability of the local sea-port's logistics infrastructure. This critically needed comprehensive research evaluates the impact of the current logistics infrastructure condition on the competitiveness of terminals and quantitatively compares the competencies of these terminals. In order to meet such requirements, the paper first summarizes the indicators of the logistics infrastructures of the sea ports before developing and testing hypotheses to reveal the correlation between the given factors and the annual throughput of container terminals in the region. Factor analysis will then be applied to score the logistics infrastructure competency of each container terminal. A significant gap between logistics infrastructures among all container terminals was not observed and the competitiveness between container terminals is mostly driven by traditional activities including cargo handling and storage. According to the results, strategic thinking will be needed to contribute to related organizations for better decisions in investment, management, and operation.

• Journal of Navigation and Port Research
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• v.39 no.2
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• pp.131-140
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• 2015

The main aim of this paper, via the method of statistical data analysis, is to analyze the current situation of the shipping industry and policies of the shipping industry in Vietnam. Section 1 gives some key information about the current situation of the shipping industry in Vietnam such as: shipping companies and their fleets, seafarers and ports. In view of the many restrictions faced by the Vietnamese shipping industry, section 2 is used to disclose the policies issued by the Vietnamese government in order to help the domestic maritime industry develop further in the near future, and the outcomes of implementing these policies. Besides the fact that some of the measures were feasible and reasonable, some others were not as effective as they were supposed to be, or in fact the initial forecast of their effectiveness was far-fetched. In the last section, after analyzing reasons for the failures, the author proposes that focusing on coastal transportation routes, fleet and port restructuring and skilled labour training were truly necessary to the development of the industry in the immediate period. Furthermore, this paper is also expected to provide a basic foundation for further research by the authors about 'the strategical approach for the development of shipping industry in developing countries: a case of Vietnam' in the near future.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.4
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• pp.41-50
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• 2020

The paper aims to investigate auditors, auditing firms and other external factors that affect quality of information technology audit in Vietnam. We conducted 2 types of data collections including direct and on survey. For direct survey, we sent directly to auditors at the training classes organized by State Securities Exchanges Commission. An online survey was established and Google doc link was provided to the Big4 and non-Big4 auditors. We received 138 survey responses in that 90 auditors came from Big4 and 48 auditors from non-Big4 firms. The data are analyzed using a factor analysis and compare means approaches to illustrate the potential IT audit quality factors and identify differences between two groups of auditors. The results show that independence and accounting knowledge and audit skills are the most important factors. And since external auditors perform many assurance services, the independence is critical. The result also shows that the auditors need to have enough competent and professional skills when conducting an audit, especially within an IT environment that requires high quality. The findings suggest a similar pattern of two groups in the context of Vietnam and some factors of auditors and auditing firms appear to have a statistically significant impact on quality of IT audit.

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.212-212
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• 2017

• IEIE Transactions on Smart Processing and Computing
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• v.1 no.1
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• pp.1-7
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• 2012

This paper presents a system used to automatically recognize the road traffic control gestures of police officers. In this approach,the control gestures of traffic police officers are captured in the form of depth images.A human skeleton is then constructed using a kinematic model. The feature vector describing a traffic control gesture is built from the relative angles found amongst the joints of the constructed human skeleton. We utilize Support Vector Machines (SVMs) to perform the gesture recognition. Experiments show that our proposed method is robust and efficient and is suitable for real-time application. We also present a testbed system based on the SVMs trained data for real-time traffic gesture recognition.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.682-686
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• 2003

This paper is concerned with 'reverse difference' of marine sediments at the Camau tongue in the extreme south of Vietnam. We demonstrate the importance of remote sensing in geomorphology and marine geological application, using only visual evaluation and some data-processing techniques. In this paper, about 10,000 km$^2$ of the territorial water in the extreme south of Vietnam is being studied. We show that form and behavior of Mekong and its branch can be determined by visually interpreting remote sensing images and using ERDAS IMAGE 8.5 software. Besides, the 'reverse difference' phenomenon is explained by flows of Mekong river and its branches.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.06a
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• pp.234-236
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• 2011

Saigon Port within the port system of the Vietnam Maritime sector is one of the port having highest throughput and productivity in the country. The marine traffic of Saigon water ways is the heaviest in Vietnam and the number of marine accidents in this area are much higher than the others area in Vietnam. In order to reduce the risk of the accident in Saigon fairway, this paper concentrates on marine accident frequency in this area. The marine traffic and the marine accident were analyzed to find out the probability of vessel collision and the marine traffic risk. It follows that the main shipping route through Saigon fairway has the high risk of ship-ship collision.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.166-166
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• 2017

Nowadays, container transport services play a substantial role in global cargo transportation by serving as an intermodal between the exporter and importer. Container shipping has become increasingly important over the past few decades due to its obvious advantages. However, Vietnam's container market has shown severely ongoing competition among numerous domestic and foreign shipping lines resulting in serious consequences occurring such as the freight rates substantially decreasing within the last ten years. In fact, Vietnam's sea lanes have become more defensive to cover the losses of shipping companies. Selection of criteria for competitive evaluation of container transport companies is necessary to help recognize the problems within the enterprise especially relating to its position in the market and from here, business management are able to put strategic plans in place and reasonable policy in order to be able to survive and grow.