Journal articles: 'Scanner in chemistry'

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Burde, Alexandru Victor, Marius Manole, Radu-Septimiu Campian, Cosmin Sinescu, and Sorana Baciu. "In vitro Comparison of Accuracy of Two Scanners Used in Dental Medicine." Revista de Chimie 70, no. 7 (August 15, 2019): 2344–46. http://dx.doi.org/10.37358/rc.19.7.7336.

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This experimental study aims to highlight and compare the resolution and accuracy (trueness and fidelity) of an intraoral scanner and a laboratory scanner. In order to achieve the aim of this study, an experimental model consisting of a die with a standard preparation for a porcelain-fused to metal crown was manufactured from a physiognomic polymethylmethacrylate resin. The experimental model was scanned with an industrial CT to obtain the virtual reference model. Then, the die was scanned 15 times with each scanner. In order to asses trueness, comparisons were made with the virtual reference model, and for fidelity, the first scan in the series was compared with the following scans. In regards to the trueness of the scanners, the average deviation for the laboratory scanner is 4.31 and 17.34 mm for the intraoral scanner. When comparing the serial scannings� of the same die, the lowest recorded deviation is 6.4 mm for the laboratory scanner and 21.57mm for the intraoral scanner. For both fidelity and trueness, the F test demonstrates that there is a statistically significant difference between the scanners and the applied T-tests confirm the lower degree of error-rate generation by the laboratory scanner. The dimensional limitations imposed for the intraoral scanners have a direct consequence on their trueness and fidelity when compared to their laboratory counterparts.

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Bohner, Lauren, Daniel Habor, Klaus Radermacher, Stefan Wolfart, and Juliana Marotti. "Scanning of a Dental Implant with a High-Frequency Ultrasound Scanner: A Pilot Study." Applied Sciences 11, no. 12 (June 14, 2021): 5494. http://dx.doi.org/10.3390/app11125494.

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The purpose of this in vitro study was to assess the trueness of a dental implant scanned using an intraoral high-frequency ultrasound prototype and compared with conventional optical scanners. An acrylic resin cast containing a dental implant at position 11 was scanned with a fringe projection 3D sensor for use as a reference dataset. The same cast was scanned 10 times for each group. Ultrasound scanning was performed with a high-frequency probe (42 MHz, aperture diameter of 4 mm and focus length of 8 mm), and 3D images were reconstructed based on the depth of each surface point echo. Optical scans were performed in a laboratory and with an intraoral scanner. A region of interest consisting of the dental implant site was segmented and matched to the reference dataset. Trueness was defined as the closeness between experimental data and the reference surface. Statistical analysis was performed with one-way ANOVA and post-hoc tests with a significance level of p = 0.05. No statistical difference was found among the evaluated scanners. The mean deviation error was 57.40 ± 17.44 µm for the ultrasound scanner, 75.40 ± 41.43 µm for the laboratory scanner and 38.55 ± 24.34 µm for the intraoral scanner. The high-frequency ultrasound scanner showed similar trueness to optical scanners for digital implant impression.

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Khan, Zohaib, Faisal Shafait, and Ajmal Mian. "Converting a Common Low-Cost Document Scanner into a Multispectral Scanner." Sensors 19, no. 14 (July 20, 2019): 3199. http://dx.doi.org/10.3390/s19143199.

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Forged documents and counterfeit currency can be better detected with multispectral imaging in multiple color channels instead of the usual red, green and blue. However, multispectral cameras/scanners are expensive. We propose the construction of a low cost scanner designed to capture multispectral images of documents. A standard sheet-feed scanner was modified by disconnecting its internal light source and connecting an external multispectral light source comprising of narrow band light emitting diodes (LED). A document was scanned by illuminating the scanner light guide successively with different LEDs and capturing a scan of the document. The system costs less than a hundred dollars and is portable. It can potentially be used for applications in verification of questioned documents, checks, receipts and bank notes.

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Bucuresteanu, Anca, Dan Prodan, and Adrian Motomancea. "Execution of Plastic Parts Using 3D Scanners and 3D Printers." Materiale Plastice 55, no. 2 (June 30, 2018): 215–18. http://dx.doi.org/10.37358/mp.18.2.4998.

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In this paper, the authors show a part of research works performed on the use of 3D scanners and 3D printers to execute plastic parts with complex surfaces. 3D scanning allows copying of certain surfaces in our environment, based on existing models. Scanned models may represent various objects, made of a wide range of materials: metals, ceramics, fabrics, plastics, leather, organic materials etc. [1]. This paper shows the results achieved using a scanner and a common and affordable - low-price - printer. 3D scanners and printers allow execution of clones of certain parts with irregular surfaces.

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Burde, Alexandru Victor, Cristina Gasparik, Marioara Moldovan, Sorana Baciu, and Cosmin Cosma. "In vitro Evaluation of Accuracy of Single Dies Captured by Two Intraoral Digital Scanners." Materiale Plastice 55, no. 2 (June 30, 2018): 176–78. http://dx.doi.org/10.37358/mp.18.2.4988.

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The objective of this in-vitro study was to compare the accuracy, defined as trueness and precision, of two intraoral digital scanners that use different capturing techniques. An experimental reference object consisting of a die was manufactured from a PMMA resin. The reference object was digitized with an industrial CT and was scanned 15 times with each scanner. In order to asses trueness, comparisons were made with the virtual reference model, and for fidelity, the first scan in the series was compared with the following scans. For both fidelity and trueness, the F test and T tests demonstrate that there is a statistically significant difference between the scanners.

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Nam, Na-Eun, Seung-Ho Shin, Jung-Hwa Lim, Bora Lee, June-Sung Shim, and Jong-Eun Kim. "Accuracy of Implant Position Reproduction According to Exposed Length of the Scan Body during Optical Scanning: An In Vitro Study." Applied Sciences 11, no. 4 (February 13, 2021): 1689. http://dx.doi.org/10.3390/app11041689.

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Accuracy of implant position reproduction according to various types of scanners, implant placement depths, and tooth positions are unknown. The purpose of this study was to compare the accuracy of implant position reproduction for differences in the exposed length of the implant scan body according to scanner type and tooth position. Implants were placed at the positions of the lateral incisor, first premolar, and first molar in the study model at the bone level and submerged 1.5 mm, 3.0 mm, 4.5 mm, and 6.0 mm. The completed models were scanned with one type of tabletop scanner and three types of intraoral scanners (TRIOS 3, i500, and CS3600). A matching process was performed for all scan data to superimpose abutment library data on the scan body, and the root mean square errors were analyzed in three dimensions to evaluate the position reproducibility of the replaced abutment library. In the trueness analysis, the error increased rapidly for an implant placement depth of 4.5 mm, and was largest for a submersion of 6.0 mm. The precision analysis confirmed that the error increased for depths of at least 3.0 mm. The analysis by position identified that the accuracy was lowest for an implant placed at the position of the lateral incisor. These findings indicate that special care is required when making an impression of a deep implant with an optical scanner.

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Tóth, Teodor, Patrik Varga, Branko Štefanovič, Lucia Bednarčíková, Marek Schnitzer, Radovan Hudák, and Jozef Živčák. "Accuracy Verification of an Anatomical Model Manufactured Using Low-Cost Additive Production." Applied Sciences 11, no. 2 (January 9, 2021): 594. http://dx.doi.org/10.3390/app11020594.

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The paper deals with the separation of the third cervical vertebra using the software VGStudio MAX, Mimics, and inVesalius. During the separation, various parameters of the threshold were used to determine the effect. The comparison of models from Mimics and inVesalius to VGStudio MAX showed that the cumulative variance distribution for 95% surface coverage is less than 0.935 mm. When comparing medically oriented software, Mimics and inVesalius, the deviation was less than 0.356 mm. The model was made of polylactic acid (PLA) material on a low-cost 3D printer, Prusa i3 MK2.5 MMU1. The printed model was scanned by four scanners: Artec Eva, 3Shape D700, Steinbichler Comet L3D, and Creaform EXAscan. The outputs from the scanners were compared to the reference model (standard tessellation language (STL) model for 3D printing) as well as to the scanner with the best accuracy (3Shape). Compared to the publications below, the analysis of deviations was evaluated on the entire surface of the model and not on selected dimensions. The cumulative variance distribution for comparing the output from the 3D scanner with the reference model, as well as comparing the scanners, shows that the deviation for 95% of the surface coverage is at the level of 0.300 mm. Since the model of the vertebra is planned for education and training, the used software and technologies are suitable for use in the design and the production process.

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Motomancea, Adrian, Anca Bucuresteanu, and Dan Prodan. "Execution of Non-Metallic or Metallic Duplicates, Cast with 3D Scanners and 3D Printers." Materiale Plastice 56, no. 1 (March 30, 2019): 6–10. http://dx.doi.org/10.37358/mp.19.1.5113.

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In this paper, the authors show a part of research works performed on the use of 3D scanners and 3D printers to execute the molds required for the cast of parts with complex surfaces. 3D scanning allows copying of certain surfaces in our environment, based on existing models. The finished parts may also be executed from metals that are relatively easy to cast (bronze, aluminum etc.). In order to execute the molds destined for the casting, various pieces may be scanned, with a volume size in the range of [150x150x200 mm3 ÷ 500x500x2000 mm3]. Plastic model printing is performed depending on the capacity of the 3D printer used. This paper shows the results achieved with general-purpose scanner and printer, valued at affordable prices.

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Pantea, Mihaela, Robert Ciocoiu, Ana Maria Cristina Tancu, Daniela-Mădălina Nină, Alexandru Petre, Iulian Vasile Antoniac, and Marina Melescanu-Imre. "Comparative Study on Two Methods Used in Obtaining 3D Printed Dental Models." Materiale Plastice 56, no. 4 (December 30, 2019): 812–16. http://dx.doi.org/10.37358/mp.19.4.5270.

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The purpose of this study was to assess the accuracy of two 3D printed dental models manufactured after intraoral/IO and extraoral/EO scanning. A dental study model (KaVo Dental GmbH/Germany) was used as a reference for this research; this model was scanned with an industrial scanner (XT H 225 ST/Industrial CT scan/Nikon Metrology Inc./U.S.A.) and a reference STL file was generated (coded M1). Two 3D printed models (Form2/FormLabs Inc./U.S.A.) were produced via IO scanning (TRIOS 3 Battery Cart/3 Shape/Denmark), respectively via EO scanning (Swing Dental Scanner/Dof Inc./South Korea) of the reference dental model. The 3D printed models obtained were scanned with the industrial scanner, resulting in other two STL files (coded M2, respectively M3). All the STL files obtained (reference M1; M2; M3) were compared in pairs, using a 3D analysis software. Good results were achieved in obtaining 3D printed dental models via IO or EO scanning, yet, the 3D printed dental model obtained via IO scanning (M3) showed slightly improved dimensional compatibility with the reference model (M1) in comparison with the 3D printed dental model manufactured via EO scanning (M2).

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Ozaki, Takashi, Norikazu Ohta, and Motohiro Fujiyoshi. "Wide Two-Degree-of-Freedom Static Laser Scanner with Miniaturized Transmission Mechanism and Piezoelectric Actuation." Sensors 21, no. 18 (September 10, 2021): 6077. http://dx.doi.org/10.3390/s21186077.

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In recent years, laser scanners have attracted significant attention for applications such as laser radars. However, the establishment of a two-degree-of-freedom scanner that can quasi-statically drive a large mirror with a large deflection angle has proven to be challenging. In this paper, we propose a laser scanner design and fabrication method by combining two unimorph piezoelectric actuators composed of piezoelectric single-crystal Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 and a miniature translation-rotation conversion mechanism with flexible polyimide hinges. The size of the entire scanner was 32 mm × 12 mm × 10 mm. We successfully demonstrated that the scanner could achieve a large quasi-static mechanical deflection angle amplitude of 20.5° in two axes with a 6-mm-square mirror.

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Aldridge, P. K., J. B. Callis, and D. H. Burns. "Laptop Chemistry: A Compact, Portable Thin Layer Scanner." Journal of Liquid Chromatography 13, no. 14 (August 1990): 2829–39. http://dx.doi.org/10.1080/01483919008049073.

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Velas, Martin, Michal Spanel, Tomas Sleziak, Jiri Habrovec, and Adam Herout. "Indoor and Outdoor Backpack Mapping with Calibrated Pair of Velodyne LiDARs." Sensors 19, no. 18 (September 12, 2019): 3944. http://dx.doi.org/10.3390/s19183944.

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This paper presents a human-carried mapping backpack based on a pair of Velodyne LiDAR scanners. Our system is a universal solution for both large scale outdoor and smaller indoor environments. It benefits from a combination of two LiDAR scanners, which makes the odometry estimation more precise. The scanners are mounted under different angles, thus a larger space around the backpack is scanned. By fusion with GNSS/INS sub-system, the mapping of featureless environments and the georeferencing of resulting point cloud is possible. By deploying SoA methods for registration and the loop closure optimization, it provides sufficient precision for many applications in BIM (Building Information Modeling), inventory check, construction planning, etc. In our indoor experiments, we evaluated our proposed backpack against ZEB-1 solution, using FARO terrestrial scanner as the reference, yielding similar results in terms of precision, while our system provides higher data density, laser intensity readings, and scalability for large environments.

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Guerra, Maria Grazia, Leonardo De Chiffre, Fulvio Lavecchia, and Luigi Maria Galantucci. "Use of Miniature Step Gauges to Assess the Performance of 3D Optical Scanners and to Evaluate the Accuracy of a Novel Additive Manufacture Process." Sensors 20, no. 3 (January 29, 2020): 738. http://dx.doi.org/10.3390/s20030738.

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In this work, we show how miniature step gauges featuring unidirectional and bidirectional lengths can be used to assess the performance of 3D optical scanners as well as the accuracy of novel Additive Manufacturing (AM) processes. A miniature step gauge made of black polyphenylene sulfide (PPS) was used for the performance verification of three different optical scanners: a structured light scanner (SLS), a laser line scanner (LLS), and a photogrammetry-based scanner (PSSRT), having comparable resolutions and working volumes. Results have shown a good agreement between the involved scanners, with errors below 5 μm and expanded uncertainties below 10 μm. The step gauge geometry due to the bidirectional lengths, highlights that there is a different interaction between the optical properties of the step gauge under measurement and each optical instrument involved and this aspect has to be considered in the uncertainty budget. The same geometry, due to its great significance in the detection of systematic errors, was used, as a novelty, to evaluate the accuracy of Lithography-based Ceramics Manufacturing (LCM), a proprietary additive manufacturing technology used for the fabrication of medical implants. In particular, two miniature step gauges made of Tricalcium Phosphate (TCP) were produced. Measurements conducted with the SLS scanner were characterized by a negligible error and by an uncertainty of about 5 μm. Deviations of the manufactured step gauges with respect to the Computer Aided Designed (CAD) model were comprised between ±50 μm, with positive deviations in the order of 100 μm on vertical sides. Differences in the order of 50 μm between the two step gauges were registered.

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Bonin, Rémi, Farbod Khameneifar, and J. R. R. Mayer. "Evaluation of the Metrological Performance of a Handheld 3D Laser Scanner Using a Pseudo-3D Ball-Lattice Artifact." Sensors 21, no. 6 (March 18, 2021): 2137. http://dx.doi.org/10.3390/s21062137.

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This paper proposes the use of a pseudo-3D ball-lattice artifact to characterize a handheld laser scanner from a metrological standpoint. The artifact allows the computation of local and global errors in measurement by using the reference-frame-independent parameters of size, form, and distance within the measuring volume of the scanner, and in a single point cloud, without the need for registration. A set of tests was performed using the whole measuring volume, and three acquisition parameters, namely the orientation of the sweeps during the scans, the exposure time, and the distance to the scanner were analyzed for their effects on the accuracy of the scan data. A composite error including the errors in measuring size, form, and distance was used as a single figure of merit to characterize the performance of the scanner in relation to the data-acquisition parameters. The orientation of sweeps did not have a considerable effect on the errors. The accuracy of the scan data was strongly affected by exposure time and its interaction with the distance at which the artifact was scanned. The errors followed a quadratic trend with respect to the distance of the artifact to the scanner. The tested scanner performed best at its manufacturer’s recommended stand-off distance.

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Gabor, Alin, Tiberiu Hosszu, Cristian Zaharia, Alexandru Kozma, Andreea Codruta Cojocariu, Meda Lavinia Negrutiu, Camelia Szuhanek, and Cosmin Sinescu. "3D Printing of a Mandibular Bone Deffect." Materiale Plastice 54, no. 1 (March 30, 2017): 29–31. http://dx.doi.org/10.37358/mp.17.1.4778.

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The aim of this study was to achieve a polymeric scaffold, ex-vivo, using 3D printing technology and then subjecting it to various tests to check its optimal property. Initially there was selected a lower jaw with a bone defect that would have prevented any treatment based prosthetic implant. The mandible was first scanned using an optical scanner (MAESTRO DENTAL SCANNER MDS400). The scanning parameters using optical scanning system are: 10 micron accuracy, resolution 0.07 mm, 2 rooms with High-Resolution LED structured light, two axes. The scan time of the mandible was 4-5 min. Later the same mandible was scanned using CBCT�s CRANEX 3DX. The images obtained using CBCT�s were correlated with those obtained by optical scanning. Further on, there was achieved the digital design of the future scaffold with the conventional technique of wax addition directly on the mandibular bone defect. After that, this was again scanned using scanning system MAESTRO DENTAL SCANNER MDS400, and using CBCT�s CRANEX 3DX. The images obtained were correlated with all the scanned images of original mandible bone defects. There were made two polymeric scaffolds using 3D printing system an (D20 Digital Wax System 3D Printer). After printing, scaffold sites were introduced for 30 minutes in an oven curing. Later the pieces obtained were processed to remove small excesses of work. There were obtained 3 blocks of polymers that have a good adaptation to the bone profile. Often, in oral implantology and maxillofacial surgery appear bone defects. They prevent an optimal treatment of bio-functional and aesthetic restoration. Using 3D printing technology one can achieve scaffold sites of different biocompatible materials that have optimal properties to replace bone defect and restore the defective area. These scaffold sites have an intimate adaptation to the defect. 3D printing techniques used to restore bone defects can quickly and efficiently give the possibility to have a successful implantology prosthetics treatment.

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Duma, Virgil-Florin, and Alexandru-Lucian Dimb. "Exact Scan Patterns of Rotational Risley Prisms Obtained with a Graphical Method: Multi-Parameter Analysis and Design." Applied Sciences 11, no. 18 (September 12, 2021): 8451. http://dx.doi.org/10.3390/app11188451.

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Rotational Risley prisms are one of the fastest two-dimensional (2D) optomechanical scanning systems. Their drawback is the strong non-linearity of the scan patterns they produce, in contrast to the most common (but slower) raster scanning modalities of 2D dual axis galvanometer scanners (GSs) or Micro-Electro-Mechanical Systems (MEMS) with oscillatory mirrors. The aim of this work is to develop a graphical method, which, to our knowledge, we have introduced to determine and characterize, using a commercially-available mechanical design program (for example CATIA V5R20 (Dassault Systems, Paris, France)) to simulate the exact scan patterns of rotational Risley prisms. Both the maximum and minimum angular and linear deviations of this type of scanner are deduced theoretically to characterize the outer diameter/Field-of-View (FOV) and the inner diameter (of the blind zone) of its ring-shaped patterns, respectively. This multi-parameter analysis is performed in correlation with the shape of the scan patterns, considering the four possible configurations of laser scanners with a pair of rotational Risley prisms, as well as all their parameters: prisms angles, refractive indexes, rotational speeds, distance between the two prisms, and the distance from the system to the scanned plane. Marshall’s synthetic parameters are also considered, i.e., the ratios of the rotational velocities and of the angles of the prisms. Rules-of-thumb for designing this optomechanical scanner are extracted from this analysis, regarding both shapes and dimensions of the scan patterns to be produced. An example of experimental validation completes the mathematical analysis and the performed simulations.

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Kudoh, Atsushi. "EV-Web Scanner." JAPAN TAPPI JOURNAL 55, no. 11 (2001): 1550–54. http://dx.doi.org/10.2524/jtappij.55.1550.

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Liu, Lu, Ming Kong, Sen Wu, Xinke Xu, and Daodang Wang. "Error Analysis of the Combined-Scan High-Speed Atomic Force Microscopy." Sensors 21, no. 18 (September 13, 2021): 6139. http://dx.doi.org/10.3390/s21186139.

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A combined tip-sample scanning architecture can improve the imaging speed of atomic force microscopy (AFM). However, the nonorthogonality between the three scanners and the nonideal response of each scanner cause measurement errors. In this article, the authors systematically analyze the influence of the installation and response errors of the combined scanning architecture. The experimental results show that when the probe in the homemade high-speed AFM moves with the Z-scanner, the spot position on the four-quadrant detector changes, thus introducing measurement error. Comparing the experimental results with the numerical and theoretical results shows that the undesired motion of the Z-scanner introduces a large error. The authors believe that this significant error occurs because the piezoelectric actuator not only stretches along the polarization direction but also swings under nonuniform multifield coupling. This article proposes a direction for further optimizing the instrument and provides design ideas for similar high-speed atomic force microscopes.

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Shely, Asaf, Shiri Livne, Gil Ben-Izhack, Michal Lokshin, Shahar Har-Nes, Helena Zelikman, Sigalit Blumer, and Eran Dolev. "The Influence of Laboratory Scanner Versus Intra-Oral Scanner on Determining the Implant Axis by Using Three Different Scan Abutments." Applied Sciences 11, no. 18 (September 14, 2021): 8543. http://dx.doi.org/10.3390/app11188543.

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Background: The purpose of this in vitro study was to compare the implant axis’ spatial position and orientation by using laboratory scanner versus intra-oral scanner with three different scan abutments. Methods: A 3D model was printed with an internal hex implant analog in the place of teeth 35#. Three standard scan abutments were used: MIS (two-piece titanium), AB (two-piece PEEK and titanium base) and ZZ (one-piece PEEK). Each scan abutment was scanned 30 times by TRIOS E3 (laboratory scanner) and 30 times by Omnicam (intra-oral scanner). For each scan, an STL (stereolithography) file was created, and the spatial characterization of each scan abutment was measured in the X, Y, Z coordinates, and rotational and longitudinal angles. The comparison between all the scans was conducted by superimposition of the STL files, using a 3D software. A t-test and Wilcoxon signed-rank test were used. (p < 0.05) Results: Only the MIS scan abutment showed no statistical difference in the X and Z axes. (p < 0.05). All other scan abutments showed a statistical difference in all axes. The rotational angle of the AB scan abutment was twice the angle of the MIS and ZZ scan abutments. Conclusions: All three scan abutments showed a rotational deviation of the implant axis between the laboratory scanner and the intra-oral scanner. The AB scan abutment showed the greatest deviation (1.04 degrees) while the other two abutments showed deviations of about half a degree in relation to the laboratory scan abutment. There is a need for further studies which will examine the influence of geometry, material, and scan abutment parts on the accuracy of the scan obtained.

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Li, Jianxiong, Qian Zhou, Xinghui Li, Ruiming Chen, and Kai Ni. "An Improved Low-Noise Processing Methodology Combined with PCL for Industry Inspection Based on Laser Line Scanner." Sensors 19, no. 15 (August 2, 2019): 3398. http://dx.doi.org/10.3390/s19153398.

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This paper introduces a three-dimensional (3D) point cloud data obtained method based on a laser line scanner and data processing technology via a PCL open project. This paper also provides a systematical analysis of the error types of laser line scanner and common error reducing solutions and calibration of the laser line scanner. The laser line scanner is combined with a precision motorized stage to obtain the 3D information of a measurand, and the format of point cloud data is converted via the set of x, y, and z coordinates. The original signal is processed according to the noise signal types of the raw point cloud data. This paper introduced a denoise process step by step combining various segmentation methods and a more optimized three-dimensional data model is obtained. A novel method for industry inspection based on the numerous point cloud for the dimensions evaluation via feature extraction and the deviation of complex surface between scanned point cloud and designed point cloud via registration algorithm is proposed. Measurement results demonstrate the good performance of the proposed methods. An obtained point cloud precision of ±10 μm is achieved, and the precision of dimension evaluation is less than ±40 μm. The results shown in the research demonstrated that the proposed method allows a higher precision and relative efficiency in measurement of dimensions and deviation of complex surfaces in industrial inspection.

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Mayrand, P. E., L. B. Hoff, L. J. McBride, J. A. Bridgham, R. Cathcart, K. P. Corcoran, G. S. Golda, D. H. Keith, E. W. Lachenmeier, and D. E. Madden. "Automation of specific human gene detection." Clinical Chemistry 36, no. 12 (December 1, 1990): 2063–71. http://dx.doi.org/10.1093/clinchem/36.12.2063.

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Abstract An instrument/chemistry system is described that automates a new chemical procedure functionally equivalent to Southern blotting. A fluorescence gel scanner that detects migrating DNA fragments in real-time analyzes the samples produced by a prototype liquid-handling instrument that automates a solution-phase hybridization/solid-phase capture chemistry for DNA analysis. The combination of this chemistry, the gel scanner, and robotic automation eliminates the tedium encountered in traditional manual methods for specific gene detection and reduces analysis time from days to hours. Restriction fragment lengths are measured with high precision by comparison with in-lane standards to minimize effects attributable to migration anomalies. The utility of this automated system is demonstrated by executing a clinical research application involving hybridization to a multi-copy repeat sequence on the Y chromosome and its detection.

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Tomelin Fabris, Bárbara, Jair Juarez João, and Endler Marcel Borges. "Nitrite Quantification in Water Using a Flatbed Scanner." Revista Virtual de Química 12, no. 3 (2020): 569–82. http://dx.doi.org/10.21577/1984-6835.20200045.

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Saskia, Visser, Hekman Henri, van Beek Christy, and van Helvoort Angelique. "Placing Soil Information in the Hands of Farmers." Proceedings 30, no. 1 (June 16, 2020): 88. http://dx.doi.org/10.3390/proceedings2019030088.

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Adequate soil information to adapt fertilizer plans and support farmers’ yield ambitions is either hard to obtain or expensive, as it often requires soil sampling and analyses in a lab. AgroCares has developed two services, i.e., the Scanner and the Lab-in-a-box, that place the knowledge of soil analysts and agronomists in the hands of the farmer in a quick, easy and affordable way. The obtained spectral image of the soil provided by the scanner is compared to data in the Global Soil Database; using machine learning regression models, the content of the soil sample is predicted based on its spectrum. The results are returned to the farmer as a soil status report. The Global Soil Database is developed country by country and starts by determining the number and location of the samples required to cover the full spectral range of the specific country using data such as soil type, land use, fertilizer and crop residue management, satellite crop development images, climate and elevation. These samples are then collected following protocols and shipped to the Golden Standard Laboratory in the Netherlands where they are analyzed using regulated, traditional wet chemistry techniques and scanned with the sensors of the Lab-in-a-Box (Mid-Infrared and XRF) and the Scanner (Near-Infrared). The reference values obtained in the GSL and the spectra for each sample obtained from the Scanner and the Lab-in-a-Box form the ground truthing data set required for the machine learning algorithms. Once all the soil data have been extracted from the spectral image, they are sent to the fertilizer module, where the different nutrients are allocated to soil fertility categories. These categories are used to establish the quantities in kg/ha of nutrients needed to reach the desired level of soil fertility. Using local nutrient crop uptake tables, the total nutrient requirements are calculated and converted into fertilizer recommendations that consider factors like nutrient loss after application and available fertilizer. The user then receives a full soil management report that includes the soil analysis results in classes of N, P, K, pH and organic matter with the Scanner, and in values of all macro- and micro- nutrients with the Lab-in-a-box.

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Perez-Cortes, Juan-Carlos, Alberto Perez, Sergio Saez-Barona, Jose-Luis Guardiola, and Ismael Salvador. "A System for In-Line 3D Inspection without Hidden Surfaces." Sensors 18, no. 9 (September 7, 2018): 2993. http://dx.doi.org/10.3390/s18092993.

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This work presents a 3D scanner able to reconstruct a complete object without occlusions, including its surface appearance. The technique presents a number of differences in relation to current scanners: it does not require mechanical handling like robot arms or spinning plates, it is free of occlusions since the scanned part is not resting on any surface and, unlike stereo-based methods, the object does not need to have visual singularities on its surface. This system, among other applications, allows its integration in production lines that require the inspection of a large volume of parts or products, especially if there is an important variability of the objects to be inspected, since there is no mechanical manipulation. The scanner consists of a variable number of industrial quality cameras conveniently distributed so that they can capture all the surfaces of the object without any blind spot. The object is dropped through the common visual field of all the cameras, so no surface or tool occludes the views that are captured simultaneously when the part is in the center of the visible volume. A carving procedure that uses the silhouettes segmented from each image gives rise to a volumetric representation and, by means of isosurface generation techniques, to a 3D model. These techniques have certain limitations on the reconstruction of object regions with particular geometric configurations. Estimating the inherent maximum error in each area is important to bound the precision of the reconstruction. A number of experiments are presented reporting the differences between ideal and reconstructed objects in the system.

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Lee, Bora, Na-Eun Nam, Seung-Ho Shin, Jung-Hwa Lim, June-Sung Shim, and Jong-Eun Kim. "Evaluation of the Trueness of Digital Implant Impressions According to the Implant Scan Body Orientation and Scanning Method." Applied Sciences 11, no. 7 (March 29, 2021): 3027. http://dx.doi.org/10.3390/app11073027.

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This study investigated the trueness of a digital implant impression according to the orientation of the implant scan body (ISB) and the scanning method. With the flat surface of the ISB facing either the buccal or proximal direction, the ISB was scanned using one tabletop scanner (T500) and three types of intraoral scanner (TRIOS 3, CS3600, and i500). The effects of differences in the scanning method and ISB orientation were assessed. Postalignment data were subsequently obtained with the abutments generated using a digital library, and superimposed with reference data using a best-fit algorithm, followed by root-mean-square error (RMSE) analysis. The RMSE was lower in the buccal groups (28.15 ± 8.87 μm, mean ± SD) than in the proximal groups (31.94 ± 8.95 μm, p = 0.031), and lower in the full-scan groups (27.92 ± 10.80 μm) than in the partial-scan groups (32.16 ± 6.35 μm, p = 0.016). When using the tabletop scanner, the trueness was higher when the ISB was connected buccally (14.34 ± 0.89 μm) than when it was connected proximally (29.35 ± 1.15 μm, p < 0.001). From the findings of this study it can be concluded that the operator should connect the ISB so that its flat surface faces the buccal direction, and attempt to scan all areas. Additionally, it is advantageous to connect an ISB buccally when using a tabletop scanner.

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Lee, Ye-Chan, Jong-Eun Kim, Na-Eun Nam, Seung-Ho Shin, Jung-Hwa Lim, Keun-Woo Lee, and June-Sung Shim. "Influence of Edentulous Conditions on Intraoral Scanning Accuracy of Virtual Interocclusal Record in Quadrant Scan." Applied Sciences 11, no. 4 (February 6, 2021): 1489. http://dx.doi.org/10.3390/app11041489.

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Reproduction of the exact interocclusal relationship using digital workflow is crucial for precise fabrication of accurate prostheses. Intraoral scanner is known to be valid for the measurement of quadrants, however, the role of missing area in the quadrant scan on the virtual interocclusal record (VIR) is uncertain. This study aimed to evaluate the accuracy of VIR in quadrant scans using an intraoral scanner (IOS) under four different edentulous conditions. Eight scans per group were obtained using a laboratory scanner and three IOSs (Trios3, CS3600, i500). Based on trueness and precision, Trios3 had the best results, followed by CS3600 and i500. The trueness and precision were affected by edentulous conditions. The three IOSs showed deviation in the posterior region during assessment of VIR for the missing area with posterior support. CS3600 and i500 showed deviation in the short-span edentulous area without support. In extended edentulous condition without support, Trios3 showed overclosure, while i500 showed an angular deviation. In some groups scanned with Trios3 and i500, the tilting effect was observed. Based on the edentulous condition and type of IOS used, local or general deviations in occlusion were seen. The accuracy of VIR was dependent on accurate scan data. Thus, registration of the occlusal relationship in an edentulous area with more than two missing teeth using IOSs may be clinically more inaccurate than that with a laboratory scanner.

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Luxembourg, Stefan L., Ali R. Vaezaddeh, Erika R. Amstalden, Catherine G. Zimmermann-Ivol, Denis F. Hochstrasser, and Ron M. A. Heeren. "The molecular scanner in microscope mode." Rapid Communications in Mass Spectrometry 20, no. 22 (2006): 3435–42. http://dx.doi.org/10.1002/rcm.2747.

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Michail, Christos, George Karpetas, Nektarios Kalyvas, Ioannis Valais, Ioannis Kandarakis, Kyriakos Agavanakis, George Panayiotakis, and George Fountos. "Information Capacity of Positron Emission Tomography Scanners." Crystals 8, no. 12 (December 9, 2018): 459. http://dx.doi.org/10.3390/cryst8120459.

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Background: The aim of the present study was to assess the upper information content bound of positron emission tomography (PET) images, by means of the information capacity (IC). Methods: The Geant4 Application for the Tomographic Emission (GATE) Monte Carlo (MC) package was used, and reconstructed images were obtained by using the software for tomographic image reconstruction (STIR). The case study for the assessment of the information content was the General Electric (GE) Discovery-ST PET scanner. A thin-film plane source aluminum (Al) foil, coated with a thin layer of silica and with a 18F-fludeoxyglucose (FDG) bath distribution of 1 MBq was used. The influence of the (a) maximum likelihood estimation-ordered subsets-maximum a posteriori probability-one step late (MLE-OS-MAP-OSL) algorithm, using various subsets (1 to 21) and iterations (1 to 20) and (b) different scintillating crystals on PET scanner’s performance, was examined. The study was focused on the noise equivalent quanta (NEQ) and on the single index IC. Images of configurations by using different crystals were obtained after the commonly used 2-dimensional filtered back projection (FBP2D), 3-dimensional filtered back projection re-projection (FPB3DRP) and the (MLE)-OS-MAP-OSL algorithms. Results: Results shown that the images obtained with one subset and various iterations provided maximum NEQ values, however with a steep drop-off after 0.045 cycles/mm. The single index IC data were maximized for the range of 8–20 iterations and three subsets. The PET scanner configuration incorporating lutetium orthoaluminate perovskite (LuAP) crystals provided the highest NEQ values in 2D FBP for spatial frequencies higher than 0.028 cycles/mm. Bismuth germanium oxide (BGO) shows clear dominance against all other examined crystals across the spatial frequency range, in both 3D FBP and OS-MAP-OSL. The particular PET scanner provided optimum IC values using FBP3DRP and BGO crystals (2.4829 bits/mm2). Conclusions: The upper bound of the image information content of PET scanners can be fully characterized and further improved by investigating the imaging chain components through MC methods.

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Lassiter, H. Andrew, Travis Whitley, Benjamin Wilkinson, and Amr Abd-Elrahman. "Scan Pattern Characterization of Velodyne VLP-16 Lidar Sensor for UAS Laser Scanning." Sensors 20, no. 24 (December 21, 2020): 7351. http://dx.doi.org/10.3390/s20247351.

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Many lightweight lidar sensors employed for UAS lidar mapping feature a fan-style laser emitter-detector configuration which results in a non-uniform pattern of laser pulse returns. As the role of UAS lidar mapping grows in both research and industry, it is imperative to understand the behavior of the fan-style lidar sensor to ensure proper mission planning. This study introduces sensor modeling software for scanning simulation and analytical equations developed in-house to characterize the non-uniform return density (i.e., scan pattern) of the fan-style sensor, with special focus given to a popular fan-style sensor, the Velodyne VLP-16 laser scanner. The results indicate that, despite the high pulse frequency of modern scanners, areas of poor laser pulse coverage are often present along the scanning path under typical mission parameters. These areas of poor coverage appear in a variety of shapes and sizes which do not necessarily correspond to the forward speed of the scanner or the height of the scanner above the ground, highlighting the importance of scan simulation for proper mission planning when using a fan-style sensor.

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Chiu, Asher, Yen-Wei Chen, Juri Hayashi, and Alireza Sadr. "Accuracy of CAD/CAM Digital Impressions with Different Intraoral Scanner Parameters." Sensors 20, no. 4 (February 20, 2020): 1157. http://dx.doi.org/10.3390/s20041157.

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The advancement of intraoral scanners has allowed for more efficient workflow in the dental clinical setting. However, limited data exist regarding the accuracy of the digital impressions produced with various scanner settings and scanning approaches. The purpose of this in vitro study was to compare the accuracy of digital impressions at the crown preparation margin using different scanning resolutions of a specific intraoral scanner system. An all-ceramic crown preparation of a mandibular first molar was constructed in a typodont, and a scan (n = 3) was created with an industrial-grade laboratory scanner (3Shape D2000) as the control. Digital impressions were obtained with an intraoral scanner (3Shape TRIOS 3) under three settings—high resolution (HR), standard resolution (SR), and combined resolution (SHR). Comparative 3D analysis of scans was performed with Geomagic Control X software to measure the discrepancy between intraoral scans and the control scan along the preparation finish line. The scan time and number of images captured per scan were recorded. Statistical analysis was performed by one-way ANOVA, two-way repeated measures ANOVA, Pearson’s correlation, and Dunnett’s T3 test (α = 0.05). Significant differences were observed for scan time and for number of images captured among scan resolution settings (α < 0.05). The scan time for the SR group was, on average, 34.2 s less than the SHR group and 46.5 s less than the HR group. For discrepancy on the finish line, no significant differences were observed among scanning resolutions (HR: 31.5 ± 5.5 μm, SHR: 33.2 ± 3.7 μm, SR: 33.6 ± 3.1 μm). Significant differences in discrepancy were observed among tooth surfaces, with the distal surface showing the highest discrepancies. In conclusion, the resolution of the intra-oral scanner is primarily defined by the system hardware and optimized for default scans. A software high-resolution mode that obtains more data over a longer time may not necessarily benefit the scan accuracy, while the tooth preparation and surface parameters do affect the accuracy.

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TAGUCHI, Isamu. "Computerized tomographic scanner for iron and steel." Analytical Sciences 1, no. 1 (1985): 93–94. http://dx.doi.org/10.2116/analsci.1.93.

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Kawabata, Yoshiyuki. "Introduction of Paprican Ink-Scanner." JAPAN TAPPI JOURNAL 51, no. 2 (1997): 321–25. http://dx.doi.org/10.2524/jtappij.51.321.

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Yamada, Jumpei, Ichiro Inoue, Taito Osaka, Takato Inoue, Satoshi Matsuyama, Kazuto Yamauchi, and Makina Yabashi. "Hard X-ray nanoprobe scanner." IUCrJ 8, no. 5 (July 31, 2021): 713–18. http://dx.doi.org/10.1107/s2052252521007004.

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X-ray scientists are continually striving to improve the quality of X-ray microscopy, due to the fact that the information obtained from X-ray microscopy of materials can be complementary to that obtained from optical and electron microscopes. In contrast to the ease with which one can deflect electron beams, the relative difficulty to deflect X-ray has constrained the development of scanning X-ray microscopes (SXMs) based on a scan of an X-ray small probe. This restriction has caused severe complications that hinder progress toward achieving ultimate resolution. Here, a simple and innovative method for constructing an SXM equipped with a nanoprobe scanner is proposed. The nanoprobe scanner combines X-ray prisms and advanced Kirkpatrick–Baez focusing mirrors. By rotating the prisms on the order of degrees, X-ray probe scanning with single-nanometre accuracy can be easily achieved. The validity of the concept was verified by acquiring an SXM image of a test pattern at a photon energy of 10 keV, where 50 nm line-and-space structures were resolved. This method is readily applicable to an SXM with a single-nanometre resolution and will assist effective utilization of increasing brightness of fourth-generation synchrotron radiation sources.

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Ahdi Rezaeieh, Sasan, Ali Zamani, Konstanty Bialkowski, Graeme Macdonald, and Amin Abbosh. "Three-Dimensional Electromagnetic Torso Scanner." Sensors 19, no. 5 (February 27, 2019): 1015. http://dx.doi.org/10.3390/s19051015.

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A three-dimensional (3D) electromagnetic torso scanner system is presented. This system aims at providing a complimentary/auxiliary imaging modality to supplement conventional imaging devices, e.g., ultrasound, computerized tomography (CT) and magnetic resonance imaging (MRI), for pathologies in the chest and upper abdomen such as pulmonary abscess, fatty liver disease and renal cancer. The system is comprised of an array of 14 resonance-based reflector (RBR) antennas that operate from 0.83 to 1.9 GHz and are located on a movable flange. The system is able to scan different regions of the chest and upper abdomen by mechanically moving the antenna array to different positions along the long axis of the thorax with an accuracy of about 1 mm at each step. To verify the capability of the system, a three-dimensional imaging algorithm is proposed. This algorithm utilizes a fast frequency-based microwave imaging method in conjunction with a slice interpolation technique to generate three-dimensional images. To validate the system, pulmonary abscess was simulated within an artificial torso phantom. This was achieved by injecting an arbitrary amount of fluid (e.g., 30 mL of water), into the lungs regions of the torso phantom. The system could reliably and reproducibly determine the location and volume of the embedded target.

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Haddock, Cynthia Carter, and James W. Begun. "The Diffusion of Two Diagnostic Technologies among Hospitals in New York State." International Journal of Technology Assessment in Health Care 4, no. 4 (October 1988): 593–600. http://dx.doi.org/10.1017/s0266462300007649.

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Using combined data from an independent survey by the American Hospital Association and the State of New York, the diffusion of two diagnostic technologies–the automated chemistry analyzer and the computed tomography (CT) scanner–among hospitals in New York State was analyzed. A linearized form of the logistic function was estimated using cumulative diffusion data for each. Diffusion patterns of both technologies fit the logistic curve well, with the coefficient of diffusion for the CT scanner being greater than that for the automated analyzer. Further analysis examined characteristics of early adopters of each technology. Similar hospital characteristics (e.g., high volume of admissions and medical school affiliation) were important in explaining early adoption of both technologies.

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Siekański, Piotr, Krzysztof Magda, Krzysztof Malowany, Jan Rutkiewicz, Adam Styk, Jakub Krzesłowski, Tomasz Kowaluk, and Andrzej Zagórski. "On-Line Laser Triangulation Scanner for Wood Logs Surface Geometry Measurement." Sensors 19, no. 5 (March 2, 2019): 1074. http://dx.doi.org/10.3390/s19051074.

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The paper presents the automated on-line system for wood logs 3D geometry scanning. The system consists of 6 laser triangulation scanners and is able to scan full wood logs which can have the diameter ranging from 250 mm to 500 mm and the length up to 4000 mm. The system was developed as a part of the BIOSTRATEG project aiming to optimize the cutting of logs in the process of wood planks manufacturing by intelligent positioning in sawmill operation. This paper illustrates the detailed description of scanner construction, full measurement process, system calibration and data processing schemes. The full 3D surface geometry of products and their applied portion of selected wood logs formed after cutting out the cant is also demonstrated.

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Espinós-Morató, Héctor, David Cascales-Picó, Marina Vergara, Ángel Hernández-Martínez, José María Benlloch Baviera, and María José Rodríguez-Álvarez. "Simulation Study of a Frame-Based Motion Correction Algorithm for Positron Emission Imaging." Sensors 21, no. 8 (April 8, 2021): 2608. http://dx.doi.org/10.3390/s21082608.

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Positron emission tomography (PET) is a functional non-invasive imaging modality that uses radioactive substances (radiotracers) to measure changes in metabolic processes. Advances in scanner technology and data acquisition in the last decade have led to the development of more sophisticated PET devices with good spatial resolution (1–3 mm of full width at half maximum (FWHM)). However, there are involuntary motions produced by the patient inside the scanner that lead to image degradation and potentially to a misdiagnosis. The adverse effect of the motion in the reconstructed image increases as the spatial resolution of the current scanners continues improving. In order to correct this effect, motion correction techniques are becoming increasingly popular and further studied. This work presents a simulation study of an image motion correction using a frame-based algorithm. The method is able to cut the acquired data from the scanner in frames, taking into account the size of the object of study. This approach allows working with low statistical information without losing image quality. The frames are later registered using spatio-temporal registration developed in a multi-level way. To validate these results, several performance tests are applied to a set of simulated moving phantoms. The results obtained show that the method minimizes the intra-frame motion, improves the signal intensity over the background in comparison with other literature methods, produces excellent values of similarity with the ground-truth (static) image and is able to find a limit in the patient-injected dose when some prior knowledge of the lesion is present.

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Wang, Jun, Guangming Sun, Jiling Bai, and Li Wang. "Capillary array electrophoresis with confocal fluorescence rotary scanner." Analyst 128, no. 12 (2003): 1434. http://dx.doi.org/10.1039/b310833c.

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Prater, C. B. "New tools for Atomic Force Microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 53 (August 13, 1995): 716–17. http://dx.doi.org/10.1017/s0424820100139950.

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The Atomic Force Microscope (AFM) has been widely used in the physics, chemistry, and materials science communities, and is becoming more common in life sciences research. To better serve the biological community, new instruments have been developed recently that combine AFM and various forms of optical microscopy including EPI-fluorescence, DIC, and confocal microscopy. In addition, new techniques like fluid Tapping Mode™ have been developed to allow gentle, non-destructive imaging of biological samples, including live specimens in physiological conditions. Other new techniques can provide information about sample elasticity or molecular adhesion along with nanometerscale topography measurements.Until recently, most AFMs scanned the sample under a stationary probe using a small piezoelectric scanner. This arrangement placed serious limits on the size and type of sample that could be used as a sample substrate. Now instruments have been developed that scan the AFM probe over a fixed sample that then allows imaging of larger, more convenient sample substrates, including cover slips, slides, and even petri dishes.

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Jivănescu, Anca, Adrian Bara, Andrei-Bogdan Faur, and Raul Nicolae Rotar. "Is There a Significant Difference in Accuracy of Four Intraoral Scanners for Short-Span Fixed Dental Prosthesis? A Comparative In Vitro Study." Applied Sciences 11, no. 18 (September 7, 2021): 8280. http://dx.doi.org/10.3390/app11188280.

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Is the accuracy of the older generation of IOSs an impediment for obtaining a quality intraoral digital impression? The aim of this study was to evaluate the differences in accuracy between four intraoral scanners (two of the latest IOSs and two older IOSs) in the scenario of a short span fixed partial denture, and to determine if these differences have a major impact on the quality of the final digital impression. Four intraoral scanners: Cerec PrimeScan, Medit i700, Cerec Omnicam and Planmeca PlanScan and one laboratory scanner were used in this study. The scanned data were processed with the help of Geomagic Control X, a metrology software. For the statistical data analysis, the level of significance was set as 0.05 (α = 0.05). The Medit i700 group displayed the best level of trueness with the median value of 23.25 µm, PrimeScan group with a median of 25.55 µm, Omnicam group with a median of 32.3 µm and the PlanScan group which displayed the lowest level of trueness with a median value of 75.8 µm. From the precision data analysis, it was concluded that the PrimeScan group showed the best results, followed by Medit i700, Omnicam and the PlanScan group which showed the lowest precision. Even if there are some significant differences in accuracy between old and new IOSs, in the in vitro scenario of short span dental prostheses, the accuracy values were within the clinically acceptable range and may present important clinical implications.

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Adamczyk, Marcin, Paweł Liberadzki, and Robert Sitnik. "Temperature Compensation Method for Mechanical Base of 3D-Structured Light Scanners." Sensors 20, no. 2 (January 8, 2020): 362. http://dx.doi.org/10.3390/s20020362.

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The effect of temperature on three-dimensional (3D) structured light scanners is a very complex issue that, under some conditions, can lead to significant deterioration of performed measurements. In this paper, we present the results of several studies concerning the effect of temperature on the mechanical base of 3D-structured light scanners. We also propose a software compensation method suitable for implementation in any existing scanner. The most significant advantage of the described method is the fact that it does not require any specialized artifact or any additional equipment, nor access to the thermal chamber. It uses a simulation of mechanical base thermal deformations and a virtual 3D measurement environment that allows for conducting virtual measurements. The results from the verification experiments show that the developed method can extend the range of temperatures in which 3D-structured light scanners can perform valid measurements by more than six-fold.

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Kaloshin, Gennady, and Igor Lukin. "Interferometric Laser Scanner for Direction Determination." Sensors 16, no. 1 (January 21, 2016): 130. http://dx.doi.org/10.3390/s16010130.

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Palomer, Albert, Pere Ridao, Dina Youakim, David Ribas, Josep Forest, and Yvan Petillot. "3D Laser Scanner for Underwater Manipulation." Sensors 18, no. 4 (April 4, 2018): 1086. http://dx.doi.org/10.3390/s18041086.

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Kot, Tomáš, Zdenko Bobovský, Dominik Heczko, Aleš Vysocký, Ivan Virgala, and Erik Prada. "Using Virtual Scanning to Find Optimal Configuration of a 3D Scanner Turntable for Scanning of Mechanical Parts." Sensors 21, no. 16 (August 7, 2021): 5343. http://dx.doi.org/10.3390/s21165343.

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The article describes a method of simulated 3D scanning of triangle meshes based on ray casting which is used to find the optimal configuration of a real 3D scanner turntable. The configuration include the number of scanners, their elevation above the rotary table and the number of required rotation steps. The evaluation is based on the percentage of the part surface covered by the resulting point cloud, which determines the ability to capture all details of the shape. Principal component analysis is used as a secondary criterion to also evaluate the ability to capture the overall general proportions of the model.

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Xing, Xuefeng, Wanyao Liu, Tao Li, Shu Xing, Xueqi Fu, Dongyang Wu, Dianjun Liu, and Zhenxin Wang. "A portable optical waveguide resonance light-scattering scanner for microarray detection." Analyst 141, no. 1 (2016): 199–205. http://dx.doi.org/10.1039/c5an01839k.

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González-Merino, Ramón, Elena Sánchez-López, Pablo E. Romero, Jesús Rodero, and Rafael E. Hidalgo-Fernández. "Low-Cost Prototype to Automate the 3D Digitization of Pieces: An Application Example and Comparison." Sensors 21, no. 8 (April 7, 2021): 2580. http://dx.doi.org/10.3390/s21082580.

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This work is aimed at describing the design of a mechanical and programmable 3D capturing system to be used by either 3D scanner or DSLR camera through photogrammetry. Both methods are widely used in diverse areas, from engineering, architecture or archaeology, up to the field of medicine; but they also entail certain disadvantages, such as the high costs of certain equipment, such as scanners with some precision, and the need to resort to specialized operatives, among others. The purpose of this design is to create a robust, precise and cost-effective system that improves the limitations of the present equipment on the market, such as robotic arms or rotary tables. For this reason, a preliminary study has been conducted to analyse the needs of improvement, later, we have focused on the 3D design and prototyping. For its construction, there have been used the FDM additive technology and structural components that are easy to find in the market. With regards to electronic components, basic electronics and Arduino-based 3D printers firmware have been selected. For system testing, the capture equipment consists of a Spider Artec 3D Scanner and a Nikon 5100 SLR Camera. Finally, 3D models have been developed by comparing the 3D meshes obtained by the two methods, obtaining satisfactory results.

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FUCHS, WOLFGANG, MICHAEL DAUER, ULRICH HIRN, WOLFGANG BAUER, and D. STEVEN KELLER. "Fast evaluation of spatial coating layer formation using ultraviolet scanner imaging." August 2015 14, no. 8 (September 1, 2015): 527–35. http://dx.doi.org/10.32964/tj14.8.527.

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Print quality demands are steadily growing. Several print quality problems are known to be closely related to coating layer uniformity (e.g., print or gloss mottle). This study evaluates the potential for using ultraviolet (UV) scanner imaging as a fast method for characterization of the spatial coating layer formation. The method measures the visual light response of the excited fluorescent whitening agent (FWA) in the coating color. UV scanner imaging was compared to two reference methods for determining the coating layer uniformity, the burnout test, and β-radiography. Within the study, a commercially produced lightweight coated paper, a laboratory coated commercial woodfree base paper, and laboratory coated handsheets were examined. Image analysis showed that UV scanner imaging indeed reveals the coating layer formation, especially for lower coat weights. Furthermore, the influence of varying amounts of FWA in the coating color and in the base paper on the measurement results was investigated. The results indicate that UV scanner imaging of coating layer uniformity works best for coat weights below 20 g/m² and moderate FWA concentrations in the coating color.

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KIM, Suhyeon, Hyun Ju YOO, and Jong Hoon HAHN. "Post-Electrophoresis Capillary Scanner for Detecting DNA Sequencing Reaction Products." Analytical Sciences 12, no. 2 (1996): 371–75. http://dx.doi.org/10.2116/analsci.12.371.

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Ramaley, Louis, Margaret Anne Vaughan, and W. David Jamieson. "Characteristics of a thin-layer chromatogram scanner-mass spectrometer system." Analytical Chemistry 57, no. 1 (January 1985): 353–58. http://dx.doi.org/10.1021/ac00279a079.

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Cheng, Aiying, Junqing Yu, Chunliang Gao, and Lisha Zhang. "Comparison and correction of element measurements using qualitative and quantitative X-ray fluorescence in lacustrine sediments: A case study of Lake Hurleg." E3S Web of Conferences 198 (2020): 03035. http://dx.doi.org/10.1051/e3sconf/202019803035.

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Using an X-ray Fluorescence (XRF) core scanner with nondestructive and successive, the chemistry features of lacustrine sediment can be measured directly. This method of XRF core scanner measurements has been widely applied to core sediment analysis but uncertain of the precision and accuracy. Comparison of intensities obtained by XRF core scanning and the concentration measured by conventional X-ray Fluorescence, indicates effects of physical properties varied from different elements on elemental intensities in the lacustrine sediments of a core from Lake Hurleg in the northeastern Tibetan Plateau. Correlation among elements Ti and Sr between the two measurement methods of the XRF and the conventional XRF is high. Using the intensity of Cl as an indicator of water content, the element intensities of Ti and Sr in the core samples is corrected. But the correlation coefficients of Ti and Sr is litter raised. The results show that XRF core scanning is a very useful tool for measuring element concentration in sediments particularly for high intensities elements.

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Journal articles on the topic 'Scanner in chemistry'

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