DEVELOPMENT AND APPLICATION OF THE ENVIRONMENTAL HYDRODYNAMIC 3D MODEL FOR COMPUTATION AND FORECASTING OF OIL POLLUTIONS IN COASTAL MARINE ENVIRONMENT

Joint Research on Environmental Science and Technology for the Eart

FMI Compliant Approach to Investigate the Impact of Communication to Islanded Microgrid Secondary Control

In multi-master islanded microgrids, the inverter controllers need to share the signals and to coordinate, in either centralized or distributed way, in order to operate properly and to assure a good functionality of the grid. The central controller is used in centralized strategy. In distributed control, Multi-agent system (MAS) is considered to be a suitable solution for coordination of such system. However the latency and disturbance of the network may disturb the communication from central controller to local controllers or among agents or and negatively influence the grid operation. As a consequence, communication aspects need to be properly addressed during the control design and assessment. In this paper, we propose a holistic approach with co-simulation using Functional Mockup Interface (FMI) standard to validate the microgrid control system taking into account the communication network. A use-case of islanded microgrid frequency secondary control with MAS under consensus algorithm is implemented to demonstrate the impact of communication and to illustrate the proposed holistic approach.Comment: Proceedings of the IEEE PES ISGT Asia 2017 conferenc

ARSENIC REMOVAL FROM GROUND WATER : RESEARCHES AND PRACTICAL IMPLEMENTATION CONDUCTED AT INSTITUTE OF CHEMISTRY, VIETNAMESE ACADEMY OF SCIENCE AND TECHNOLOGY

Joint Research on Environmental Science and Technology for the Eart

Data Structure Model on the Quality of Public Passenger Transport Services by Bus in Vietnam

The system of managing public passenger transport services (PPTS) by bus is a complex system, involving infrastructure, facilities, management and service communication activities between passengers and transport systems. In particular, quality information is the most important factor, providing necessary data for analysis, setting out measures to improve quality to meet the needs of passengers and meet the requirements of related parties. According to the peculiarity of the service, this study selects a database structure model to guide the process of computerizing the management of quality of PPTS by bus in urban areas in Vietnam. The results show that four database systems reflecting the quality information of the infrastructure, means of transport, transport operation and passenger service and each database system is structured by components that ensure proper implementation of QM process according to the continuous quality improvement cycle. The components of each database system are dispersed according to the scope of management to ensure the consistency for the quality management process and facilitate the collection, processing and distribution of information of related parties. Keywords: Quality, transport services, public passengers, Vietnam. DOI: 10.7176/JESD/10-10-13 Publication date:May 31st 201

A Research on the Quality of Public Transportation Services by Bus in Vietnam

This study was conducted to assess the status of the quality of public passenger transport services by bus in Hanoi. Data were collected from regular passengers using buses as a means of transportation in the city, including passengers standing at stations, waiting shelters and on vehicles to make trips and students of some universities who use buses as a means of transportation. We employ descriptive statistics and hierarchical analysis to learn about the topic of research. The results indicate that the quality of public transport services by buses in Hanoi, which was judged by passengers quite well. In particular, the safety level, convenience, security and hygiene is up to 70%, which was higher than the highest quality level. Quality of fast level and reliability are low. Keywords: quality of services, public passenger transport, buses, Vietnam. DOI: 10.7176/RJFA/10-13-04 Publication date:July 31st 201

Ecpoc: an evolutionary computation-based proof of criteria consensus protocol

Recently, blockchain technology has been applied in many domains in our life. Blockchain networks typically utilize a consensus protocol to achieve consistency among network nodes in a decentralized environment. Delegated Proof of Stake (DPoS) is a popular mechanism adopted in many networks such as BitShares, EOS, and Cardano because of its speed and scalability advantages. However, votes that come from nodes on a DPoS network tend to support a set of specific nodes that have a greater chance of becoming block producers after voting rounds. Therefore, only a small group of nodes can be selected to become block producers. To address this issue, we propose a new protocol called Evolutionary Computation-based Proof of Criteria (ECPoC), which uses ten criteria to evaluate and select a new block procedure in each round. Next, a set of optimal weights used for maximizing the network’s decentralization level is identified through the use of evolutionary computation algorithms. The experimental results show that our consensus significantly enhances the degree of decentralization in the selection process of witness nodes compared to DPoS. As a result, ECPoC facilitates fairness between nodes and creates momentum for blockchain network developmen

Inverse analysis for transmissivity and the Red river bed's leakage factor for Pleistocene aquifer in Sen Chieu, Hanoi by pumping test under the river water level fluctuation

Aquifer parameters and riverbed hydraulic resistance to an aquifer have an important role in the quantitative assessment of groundwater sources, especially the aquifer recharge from river. The analytical determination of aquifer parameters and riverbed hydraulic resistance to the aquifer is rather complicated in case if the water level in the river fluctuates before and during the pumping test time. This is especially true for Pleistocene aquifer along the Red River in Hanoi city, where the riverbed has been changed very much during the recent decades. A trial-error inverse analysis in the parameters' determination by a group pumping test data obtained with a test located close to the Red river bank in Sen Chieu area, Phuc Tho district, Hanoi city was carried out. Before and during the pumping test time the water level in the river changed five times. The results have shown that the Pleistocene aquifer has a relatively high hydraulic conductivity of 55.5 m/day, which provides a good role in the transport of a large volume of water recharged by the river to the abstraction wells located near the river. The aquifer storage coefficient had lightly decreased with the pumping time, which is corresponding to the physical nature of that the aquifer stativity is a function of the aquifer pressure. A special point is worthwhile to be noted that the Red river bed resistance to the Pleistocene is very low, about 0.537 days, which is corresponding to the increase of the distance from the river bank further from the well in 28.4 m to have the river as a specified water level boundary of the aquifer. In contrast, the 1990's investigations had found that the Red river bed resistance to the Pleistocene aquifer to be about 130 days (Tran Minh, 1984), which is corresponding to the increase of the distance from the river bank further from the well in a thousand of meters to have the river as a specified water level boundary for the aquifer.ReferencesChristensen S., 2000. On the estimation of stream flow depletion parameters by drawdown analysis. Ground Water, 38(5), 726-734. Fetter C.W., 2001. Applied Hydrogeology. Prentice Hall-Upper Saddle River, NJ 07458. Fletcher G. Driscoll., 1987. Groundwater and Wells. Published by Johnson Division, St. Paul, Minnesota 55112, USA.Fox G.A., 2004. Evaluation of a stream aquifer analysis test using analytical solutions and field data. Journal of the American Water Resources Association. 40(3), 455-763. Hunt B., Wei J. and Clausen B., 2001. A stream depletion field experiment. Ground Water 39(2), 283-289. John H. Cushman and Daniel M. Tartakovsky (Editors), 2017. The Handbook of Groundwater Engineering. Third Edition. CRC Press. Taylors Francis Group. 6000 Broken Sound Parkway NW, Suite 300.Lough H.K. and Hunt B., 2006. Pumping test evaluation of stream depletion parameters. Ground Water. Jul-Aug, 44(4), 540-546. Mironhenco V.A. and Shestakov V.M., 1974. Fundamentals of hydromechanics. Publishers "Nedra", Moscow, Russia. Ne-Zheng Sun, 1994. Inverse Problems in Groundwater Modeling. Cluwer Academic Publishers. Nguyen Minh Lan, 2014. Report on "Study of the relationship between the Red river and groundwater, proposal of methods of determination of groundwater abstraction potential along the Red river from Son Tay to Hung Yen". Code: TNMT.02.33. Nguyen Quoc Thanh and Nguyen Van Hoang, 2007. Hydrogeomechanical processes affecting the stability of Red river dike's foundation and in the Son Tay-Ha Noi area. Hanoi Geoengineering 2007. International Conference Proceedings, 120-123. Nguyen The Chuyen, Vu Ngoc Duc, Dao Trong Tu, Nguyen Van Hoang, 2017. Study on determination of effective porosity and longitudinal dispersivity of aquifer and the application to field tracer injection test in Mo Lao, Ha Dong area, Hanoi, Vietnam. Vietnam National University Journal of Science, 33(1), 1-15. Nguyen Van Giang, Nguyen Ba Duan, Le Ngoc Thanh, Noboru Hida, 2014. Hydro-geophysical Techniques to Aquifer Locating and Monitoring for Industrial zone north Thang Long and Quang Minh, Hanoi. Vietnam J. Earth Sci., 36(3), 221-232. Doi: 10.15625/0866-7187/36/3/5905. Nguyen Van Hoang, 2016. Modelling of water pollution. Vietnam Academy of Science and Technology Publishers. Pham Dinh, 2016. Report on "Study of the effects of the sand and gravel excavation in the Red river and Thai Binh river system on the flow regime and bed load regime for supporting sustainable management and planning of sand and gravel excavation" code ĐTĐL.2012-T/27. Vietnam Academy of Water Resources. Sophocleous M., 2001. Interactions between groundwater and surface water: the state of the science. Hydrogeology Journal, 10, 52-67. Tong Ngoc Thanh, Trieu Duc Huy, Nguyen Van Kenh, Tong Thanh Tung,  Pham Ba Quyen, Nguyen Van Hoang, 2017. Methodology of determining effective porosity and longitudinal dispersivity of aquifer and the application to field tracer injection test in Southern Hanoi, Vietnam. Vietnam J. Earth Sci., 39(1), 57-75. Doi: 10.15625/0866-7187/39/1/9228. Tran Minh, 1984. Report on "Results of groundwater investigation in Hanoi area". Northern Union for Water Resources Planning and Investigation. Trieu Duc Huy (Project head), 2015. Proposal "Groundwater protection in large cities (Hanoi city)" and the project's implementation data and materials. Vietnam National Center for Water Resources Planning and Investigation. Vu Tat Uyen and Le Manh Hung, 2011. Warning on the consequences of sand and gravel excavation in the Red river more than the annual bed load supply. Journal of Water Resources Science and Technology, 3, 2-6

SEASONAL VARIATION OF PHYTOPLANKTON FUNCTIONAL GROUPS IN TUYEN LAM RESERVOIR, CENTRAL HIGHLANDS, VIETNAM

Seasonal changes in freshwater phytoplankton assemblages at Tuyen Lam Reservoir in the Central Highlands of Vietnam were classified into 23 functional groups based on physiological, morphological, and ecological characteristics. A total of 168 species were recorded during 10 surveys from 2015 to 2019 at 7 sampling sites, with Chlorophyta dominating in number of species. Phytoplankton abundance varied from 0.18×105 to 21.2×105 cells/L during the study period, mainly due to cyanobacteria. Seven of the 23 functional groups were considered to be dominant (relative density > 5%).  The dominant functional groups were groups M and G in the dry season and groups M, G, P, and E in the rainy season. Group M (Microcystis aeruginosa) was the most common in both seasons, while group P (Closterium, Staurastrum, Aulacoseira), group E (Dinobryon, Synura), and group G (Sphaerocystis, Eudorina) were more common in the rainy season. The Shannon diversity index (H¢) showed that phytoplankton communities were relatively diverse and that most of the study sites were lightly polluted. However, the ecological status has deteriorated at some locations due to the overgrowth of group M, leading to eutrophication in this reservoir. This study highlights the usefulness of functional groups in the study of seasonal changes in phytoplankton dynamics. Functional groups are applied for the first time at Tuyen Lam Reservoir and can be used to predict early-stage cyanobacterial blooms in future studies

Phenomenology of the Reduced Minimal 3-3-1 Model

The detailed analysis of the gauge model based on $\mathrm{SU}(3)_C\otimes \mathrm{SU}(3)_L \otimes \mathrm{U}(1)_X$ group with minimal content of lepton and Higgs is presented. It is shown that with just two Higgs triplets, all fermions and gauge bosons can get correct   masses. The advantage of the model under consideration is that a huge number of free parameters is reduced, and the model's predictiveness is much improved