In Vietnam, status is mentioned a lot in recent economic and management documents. The scientific basis of the position resources for socio-economic development is still a new issue in our country, and it is not accessible in the world. However, this is a significant direction that the right awareness will create a new perspective on the rational use of resources, spatial organization, and planning of rational and sustainable socio-economic development. Vietnam is particularly crucial in Southeast Asia thanks to a territory stretching over three thousand kilometers on the western edge of the South China Sea and a territorial sea area of over one million square kilometers, three times the area of the territory. The Vietnam Sea is located in a tropical monsoon region, with world-class rivers that the basin covers six countries. The Vietnam Sea plays an essential role in the environment, the ecology of the East Sea and the region, an exclusive transitional zone between the Indian Ocean and the Pacific Ocean in terms of biological and maritime geography. The development of an industrialized and modernized economy must inevitably be linked to the maritime potential of the ocean. This article presents the initial findings on the coastal and coastal status of Vietnam.

==========================================================Available online: 31 December 2020This article has been retracted by International Journal on Advanced Science, Engineering and Information Technology Editorial team, following clear correspondence and confirmation with authors.The paper is retracted from 29 November 2021.==========================================================With the advantage of reducing the damage of bending stress up to 10%, the straight-toothed bevel gears (STBG) with a shoulder-bearing are being used in many industries automobiles, trains, mining, space, machinery technology and aviation equipment. With the working characteristics of straight-tooth bevel gear, the manufacturing quality assessments are usually conducted through micro-dimensional values, surface gloss, and internal surfaces' contact ability in the transmission. Recently, research and application of gear machining methods on 3-axis CNC milling machines are gradually becoming more popular. Therefore, the study of the affection of technology parameters on the quality of shaping the STBG surface by evaluating the output factors (surface undulation, micro-geometry parameters and trace contact size) in the finishing step is very urgent. First of all, the paper goes into detail in building design solutions to create input data for the machining of STBG on CNC milling machines by profile attachment method. Moreover, the study also built the process of evaluating the machining quality of the STBG utilizing microgeometry and the contact size. The paper focuses on developing experimental equations that show the relationship between technological parameters (S, F, Z) and roughness (Ra), deviation of tooth profile shape (ff), and trace contact size (bc, hc) of the Z11-16 m8 STBG transmission. From that, the optimal technology solution was identified to ensure the contact accuracy when processing the Z16-11 m8 STBG transmission on a 3-axis CNC milling machine.

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In Vietnam, status is mentioned a lot in recent economic and management documents. The scientific basis of the position resources for socio-economic development is still a new issue in our country, and it is not accessible in the world. However, this is a significant direction that the right awareness will create a new perspective on the rational use of resources, spatial organization, and planning of rational and sustainable socio-economic development. Vietnam is particularly crucial in Southeast Asia thanks to a territory stretching over three thousand kilometers on the western edge of the South China Sea and a territorial sea area of over one million square kilometers, three times the area of the territory. The Vietnam Sea is located in a tropical monsoon region, with world-class rivers that the basin covers six countries. The Vietnam Sea plays an essential role in the environment, the ecology of the East Sea and the region, an exclusive transitional zone between the Indian Ocean and the Pacific Ocean in terms of biological and maritime geography. The development of an industrialized and modernized economy must inevitably be linked to the maritime potential of the ocean. This article presents the initial findings on the coastal and coastal status of Vietnam.