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International audience; Particle pair statistics from synthetic drifter trajectories reconstructed from realistic, high-resolution numerical simulations (SYMPHONIE model) and HF radar velocity measurements are used to investigate the dispersion properties in the Gulf of Tonkin (GoT). This study takes an approach based on two-particles statistics providing the relative dispersion, relative diffusivity and Finite Size Lyapunov Exponent (FSLE) estimates. In the GoT, the relative dispersion follows the predictions from the theory of two-dimensional turbulence with two inertial subranges identified in the kinetic energy spectrum with the spectral slopes − 5/3 and − 3. The time evolution of dispersion shows an exponential growth during 5-8 days, followed by a power law regime during the next 6-20 days. Fixed-length indicators from the relative diffusivity and the FSLE reveal a local dispersion at large and intermediate scales (above Rossby radius of deformation) and non-local dispersion in sub-mesoscale range (below Rossby radius of deformation). The effect of river runoff on the local hydrodynamics and dispersion processes is assessed using the numerical model simulations without river discharge. The results show that in the model, the river plume, when present, highly impacts the Lagrangian statistics. High gradients of buoyancy reinforce the sub-mesoscale circulation in a large region along the Vietnamese coast and modify the scales and intensity of turbulent dispersion. However, a clear change of dispersion regime in the sub-mesoscale range is not identified, suggesting that the mesoscale circulation in the GoT largely governs particle spreading even at small scale.

Step by step, Vietnam’s aim to develop the government’s integrity and actions for their citizens and corporations is being realized. One of the most important steps in reforming tax administration services is reducing corporations’ times when they are performing their tax duties (according to the Department of Central Economic Management, the time was 482 h/year in 2018, according to WB was 770 h/year in 2017). Hanoi and Ho Chi Minh City’s tax revenues have accounted for 50% of the total ones, therefore tax administrative innovations often start from Hanoi and Ho Chi Minh City. There is a need for the conception that taxpayers are customers of tax authorities. So in Hanoi, how do corporations think about tax administration services and what do tax administrative services need to complete to enhance the service quality?

This paper proposes a method for automated user interface testing of Windows-based applications to increase the accuracy in identifying the target widgets or executing several interactions. The key idea of this method is to generate new test scenarios from widgets and test specification where widgets are extracted during the execution of the application and test specification is generated by combining the interactions of widgets. Furthermore, the paper contributes some techniques to detect hidden widgets which considering as one of the most challenging problems in user interface testing. Currently, a supporting tool has been implemented and tested with several industrial projects. The details of the experimental results will be presented and discussed.

International audience; We study the daily to interannual variability of the Red River plume in the Gulf of Tonkin from numerical simulations at high resolution over 6 years (2011–2016). Compared with observational data, the model results show good performance. To identify the plume, passive tracers are used in order to (1) help distinguish the freshwater coming from different continental sources, including the Red River branches, and (2) avoid the low salinity effect due to precipitation. We first consider the buoyant plume formed by the Red River waters and three other nearby rivers along the Vietnamese coast. We show that the temporal evolution of the surface coverage of the plume is correlated with the runoff (within a lag), but that the runoff only cannot explain the variability of the river plume; other processes, such as winds and tides, are involved. Using a K-means unsupervised machine learning algorithm, the main patterns of the plume and their evolution in time are analyzed and linked to different environmental conditions. In winter, the plume is narrow and sticks along the coast most of the time due to the downcoast current and northeasterly wind. In early summer, the southwesterly monsoon wind makes the plume flow offshore. The plume reaches its highest coverage in September after the peak of runoff. Vertically, the plume thickness also shows seasonal variations. In winter, the plume is narrow and mixed over the whole water depth, while in summer, the plume can be detached both from the bottom and the coast. The plume can deepen offshore in summer, due to strong wind (in May, June) or specifically to a recurrent eddy occurring near 19°N (in August). This first analysis of the variability of the Red River plume can be used to provide a general picture of the transport of materials from the river to the ocean, for example in case of anthropogenic chemical substances leaked to the river. For this purpose, we provide maps of the receiving basins for the different river systems in the Gulf of Tonkin.Introduction