Measure of a Limestone Weathering Degree Using Laser Scanner

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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25 Jahre nationale Bodenbeobachtung im Schweizer Wald | 25 years of soil monitoring at forest sites in Switzerland

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2010.0517 ◽

2010 ◽

Vol 161 (12) ◽

pp. 517-523

Author(s):

Reto Giulio Meuli ◽

Peter Schwab

Keyword(s):

Organic Pollutants ◽

Monitoring Network ◽

Soil Protection ◽

Soil Monitoring ◽

Guide Value ◽

Sampling Campaign ◽

Forest Sites ◽

Limestone Weathering ◽

Guide Values ◽

Jurassic Limestone

The national soil monitoring network (Nabo) consists of 105 sites across Switzerland, 28 of which are located in forests. After 25 years already seven forest sites (25%) were more or less damaged by storms. Two of them had to be abandoned for a decade to recover. Concerning precautionary soil protection the legal guide value is exceeded at three forest sites for cadmium and at one site also for chromium. These sites are all based on Jurassic limestone, and it is well known that residuals of limestone weathering can be rich in cadmium. Hence, the enrichment is supposed to be of geogenic origin. In the Canton Ticino the top soil at Novaggio site exceeds the guide value for lead. Here, anthropogenic origin is very likely. The analysis of the organic pollutants PAH and PCB in the third sampling campaign revealed moderate concentrations with a maximum lower than or equal to ⅔ of the corresponding guide value. Based on the results of the first four sampling campaigns it can be concluded that only small changes in the measured heavy metal concentrations in the top soils at the 28 Nabo sites were found. The most dynamic element is lead. Most of the concentrations are far below the guide values, the same holds for the organic pollutants PAH and PCB.

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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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