Metro tunnel section test technology based on 350 degree laser scanner

Water seepage can cause serious problems in geotechnical engineering especially for construction under the water level. Baghdad metro tunnel is one of the leading vital projects to solve the major problem of crowding roadways in a highly population increase city like Baghdad. In this study, the seepage rate that will flow toward different selected points along the tunnel section across Tigris River was calculated during the excavation process, with the consideration of three different water levels of River at maximum, moderate, and minimum water depths. A three-dimensional model of the study has been modeled using the finite element software (PLAXIS 3D V20). The water seepage was observed for six different locations on each route of the tunnel. The study showed that the change of water depth in the river has no significant effect on the seepage – time curve shape. However, increasing the water level in River from minimum to maximum leads to increase the seepage rate about 15%.

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Public Interest: Agency sounds alarm on work test technology

PsycEXTRA Dataset ◽

10.1037/e382052004-026 ◽

1987 ◽

Author(s):

John Bales

Keyword(s):

Public Interest ◽

Test Technology

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Evaluation of geometrical benchmark artifacts containing multiple overhang lengths fabricated using material extrusion technique

JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES ◽

10.15282/jmes.14.3.2020.28.0573 ◽

2020 ◽

Vol 14 (3) ◽

pp. 7296-7308

Author(s):

Siti Nur Humaira Mazlan ◽

Aini Zuhra Abdul Kadir ◽

N. H. A. Ngadiman ◽

M.R. Alkahari

Keyword(s):

3D Model ◽

Laser Scanner ◽

Dimensional Accuracy ◽

Fused Deposition Modelling ◽

Layer By Layer ◽

Fused Deposition ◽

Layer Technique ◽

Subtractive Manufacturing ◽

Manufacturing Features ◽

Layer Problem

Fused deposition modelling (FDM) is a process of joining materials based on material entrusion technique to produce objects from 3D model using layer-by-layer technique as opposed to subtractive manufacturing. However, many challenges arise in the FDM-printed part such as warping, first layer problem and elephant food that was led to an error in dimensional accuracy of the printed parts especially for the overhanging parts. Hence, in order to investigate the manufacturability of the FDM printed part, various geometrical and manufacturing features were developed using the benchmarking artifacts. Therefore, in this study, new benchmarking artifacts containing multiple overhang lengths were proposed. After the benchmarking artifacts were developed, each of the features were inspected using 3D laser scanner to measure the dimensional accuracy and tolerances. Based on 3D scanned parts, 80% of the fabricated parts were fabricated within ±0.5 mm of dimensional accuracy as compared with the CAD data. In addition, the multiple overhang lengths were also successfully fabricated with a very significant of filament sagging observed.

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THREE-DIMENSIONAL ASSESSMENT OF SWELLING IN ORTHOGNATHIC SURGERY USING THE SURFACE LASER SCANNER: FUSION WITH THREE-DIMENSIONAL COMPUTED TOMOGRAPHY

10.26226/morressier.578e3b4fd462b8029238257e ◽

2016 ◽

Author(s):

Satoshi Yamamoto

Keyword(s):

Computed Tomography ◽

Orthognathic Surgery ◽

Three Dimensional ◽

Laser Scanner ◽

Surface Laser ◽

Dimensional Assessment

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INVESTIGATIONS OF THE BALTIC SEA COASTAL ZONE ABOVE-WATER PART TOPOGRAPHY DYNAMICS BY MEANS OF TERRESTRIAL LASER SCANNER (SVETLOGORSK CITY, KALININGRAD REGION)

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.31519/conferencearticle_5b1b9381375176.02831785 ◽

2017 ◽

Author(s):

Nikolay Lugovoy ◽

Askar Ilyasov ◽

Elena Pronina ◽

...

Keyword(s):

Baltic Sea ◽

Coastal Zone ◽

Coastal Erosion ◽

Laser Scanner ◽

Terrestrial Laser Scanner ◽

The Baltic Sea ◽

Coastal Dynamics ◽

Kaliningrad Region ◽

The Baltic

The paper describes application of the terrestrial laser scanner for investigation of coastal dynamics of the Svetlogorskaya Bay, Baltic Sea. Methods of investigation and results of surveys repeated over the two consecutive years for quantification of coastal erosion and slope processes within the coastal zone are presented.

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Power performance test technology of electric vehicle based on test standard

Study on Dynamical System ◽

10.35534/sds.0102007c ◽

2019 ◽

Vol 1 (2) ◽

pp. 52-57

Author(s):

Pan Haohao

Keyword(s):

Electric Vehicle ◽

Performance Test ◽

Power Performance ◽

Test Technology

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Results of studying the dimensional accuracy of the bases of complete removable prostheses made using 3D printing and traditional technologies

Стоматология для всех ◽

10.35556/idr-2020-4(93)34-39 ◽

2020 ◽

pp. 34-39

Author(s):

Vokulova Yu.A. Vokulova ◽

E.N. Zhulev

Keyword(s):

3D Printing ◽

Traditional Method ◽

Laser Scanning ◽

Laser Scanner ◽

Digital Technologies ◽

Dimensional Accuracy ◽

3D Printer ◽

Significance Level ◽

Average Value ◽

The Difference

This article presents the results of studying the dimensional accuracy of the bases of complete removable prostheses made using a 3D printer and the traditional method. Bases of complete removable prostheses were made using an intraoral laser scanner iTero Cadent (USA) and a 3D printer Asiga Max UV (Australia). To study the dimensional accuracy of the bases of complete removable prostheses, we used the DentalCAD 2.2 Valletta software. The Nonparametric Wilcoxon W-test was used for statistical analysis of the obtained data. We found that the average value of the difference with the standard for bases made using digital technologies is 0.08744±0.0484 mm. The average value of the difference with the standard for bases made by the traditional method is 0.5654±0.1611 mm. Based on these data, we concluded that the bases of complete removable prostheses made using modern digital technologies (intraoral laser scanning and 3D printer) have a higher dimensional accuracy compared to the bases of complete removable prostheses made using the traditional method with a significance level of p<0.05 (Wilcoxon's W-test=0, p=0.031). Keywords: digital technologies in dentistry, digital impressions, intraoral scanner, 3D printing, ExoCAD, complete removable dentures.

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