Pour voir les autres types de publications sur ce sujet consultez le lien suivant : Stationary scanner.
Articles de revues sur le sujet « Stationary scanner »
Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres
Consultez les 50 meilleurs articles de revues pour votre recherche sur le sujet « Stationary scanner ».
À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.
Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.
Parcourez les articles de revues sur diverses disciplines et organisez correctement votre bibliographie.
1
Rabah, Chaima Ben, Gouenou Coatrieux et Riadh Abdelfattah. « Boosting up Source Scanner Identification Using Wavelets and Convolutional Neural Networks ». Traitement du Signal 37, no 6 (31 décembre 2020) : 881–88. http://dx.doi.org/10.18280/ts.370601.
Texte intégralRésumé :
In this paper, we present a conceptually innovative method for source scanner identification (SSI), that is to say, identifying the scanner at the origin of a scanned document. Solutions from literature can distinguish between scanners of different brands and models but fail to differentiate between scanners of the same models. To overcome this issue, the approach we propose takes advantage of a convolutional neural network (CNN) to automatically extract intrinsic scanner features from the distribution of the coefficients of the diagonal high-frequency (HH) sub-band of the discrete stationary wavelet transform (SWT) of scanned images. Such information serves as a reliable characteristic to classify scanners of different/same brands and models. Experiments conducted on a set of 8 scanners yielded a model with an accuracy of 99.31% at the block level and 100% at the full image level, showcasing the potential of using deep learning for SSI and outperforming existing schemes from literature. The influence of the model’s parameters such as the input size, the training data size, the number of layers, and the number of nodes in the fully connected layer as well as the effect of the pre-processing step were investigated.
2
Dlesk, A., K. Vach, J. Šedina et K. Pavelka. « COMPARISON OF LEICA BLK360 AND LEICA BLK2GO ON CHOSEN TEST OBJECTS ». International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLVI-5/W1-2022 (3 février 2022) : 77–82. http://dx.doi.org/10.5194/isprs-archives-xlvi-5-w1-2022-77-2022.
Texte intégralRésumé :
Abstract. The contribution deals with the comparison of two laser scanners manufactured by Leica company. In BIM modelling, there is a need for fast and accurate gathering of spatial data, e.g. point clouds. Those data can be gathered by photogrammetry or laser scanning. Last years on the market, there occurred some light and easy-to-use alternatives to classic laser scanners. There were chosen two scanners that belong to the easy-to-use category. The first scanner is stationary Leica BLK360 and the second scanner is Leica BLK2GO which is a handheld scanner based on SLAM technology. Both laser scanners were tested on three different test objects. The first object is an administrative building, the second object is a historical administrative building and the third object is the vaults of the church. In all cases, only the indoor side of the objects was measured. The point clouds were compared to each other and the comparison was discussed. The parameters derived from the point clouds were also compared to the parameters read in the original documentation of the object. The comparison of the parameters may show, how those point clouds are usable for the final BIM modelling.
3
Werner, Christoph S., Jannis Gangelhoff, Simon Frey, Daniel Steiger et Alexander Reiterer. « Development of a compact pulsed time-of-flight LiDAR platform for underwater measurements ». International Hydrographic Review 29, no 2 (1 novembre 2023) : 200–207. http://dx.doi.org/10.58440/ihr-29-2-n09.
Texte intégralRésumé :
The mapping and inspection of underwater topography and infrastructure require precise and robust instrumentation which cannot be completely fulfilled by sonar or camera-based systems. At Fraunhofer IPM we have therefore built a versatile platform that implements all necessary building blocks for various laser scanner configurations targeted at subsea applications. Based on this platform, we present two scanner prototypes: One compact and lightweight multi-wavelength airborne laser scanner for deployment with unmanned aerial vehicles. It is intended for easy and fast shallow water bathymetric and topographic mapping. The second scanner is embedded in a pressure resistant housing and designed for submerged deployment on stationary or moving platforms to facilitate numerous inspection tasks. Initial tests of the scanners have been performed in an excavation pond and on a dedicated underwater measurement range. The resulting point clouds indicate promising performance in terms of resolution, accuracy, and speed. Further work will focus on extensive field tests and software optimization for increased usability.
4
Jafri, Syed Riaz un Nabi, Muhammad Owais Ali Siddiqui, Faraz Akbar, Abdul Basit, Sheraz Shamim et Saad Ahmed. « Development of a Low-Cost Stationary Laser Scanning System for Generation of Building Information Models ». Elektronika ir Elektrotechnika 28, no 6 (21 décembre 2022) : 12–20. http://dx.doi.org/10.5755/j02.eie.31374.
Texte intégralRésumé :
This paper presents a method for developing a 3D point cloud map of any indoor and outdoor vicinities using an indigenously developed stationary scanning system comprising of a single low cost 2D laser scanner. The data logging of scanner and required inertial measurement units (IMUs) has been carried out using a Robot Operating System (ROS). Multiple divergent environments have been scanned and 3D point clouds have been developed, which have been found accurate when compared to the ground truth. In addition, the Building Information Model (BIM) of the surveyed vicinities have been developed using generated point clouds. Compared to available surveying solutions present in the local market, the developed system has been found accurate, faster, economical, and user-friendly to generate structural results of the surveyed vicinities in detail.
5
Voges, R., C. S. Wieghardt et B. Wagner. « TIMESTAMP OFFSET DETERMINATION BETWEEN AN ACTUATED LASER SCANNER AND ITS CORRESPONDING MOTOR ». ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences IV-1/W1 (30 mai 2017) : 99–106. http://dx.doi.org/10.5194/isprs-annals-iv-1-w1-99-2017.
Texte intégralRésumé :
Motor actuated 2D laser scanners are key sensors for many robotics applications that need wide ranging but low cost 3D data. There exist many approaches on how to build a 3D laser scanner using this technique, but they often lack proper synchronization for the timestamps of the actuator and the laser scanner. However, to transform the measurement points into three-dimensional space an appropriate synchronization is mandatory. Thus, we propose two different approaches to accomplish the goal of calculating timestamp offsets between laser scanner and motor prior to and after data acquisition. Both approaches use parts of a SLAM algorithm but apply different criteria to find an appropriate solution. While the approach for offset calculation prior to data acquisition exploits the fact that the SLAM algorithm should not register motion for a stationary system, the approach for offset calculation after data acquisition evaluates the perceived clarity of a point cloud created by the SLAM algorithm. Our experiments show that both approaches yield the same results although operating independently on different data, which demonstrates that the results reflect reality with a high probability. Furthermore, our experiments exhibit the significance of a proper synchronization between laser scanner and actuator.
6
Xia, Sibei, Siming Guo, Jiayin Li et Cynthia Istook. « Comparison of different body measurement techniques : 3D stationary scanner, 3D handheld scanner, and tape measurement ». Journal of The Textile Institute 110, no 8 (26 décembre 2018) : 1103–13. http://dx.doi.org/10.1080/00405000.2018.1541437.
Texte intégral
7
Dixon, Robert L., et John M. Boone. « Stationary table CT dosimetry and anomalous scanner-reported values of CTDIvol ». Medical Physics 41, no 1 (18 décembre 2013) : 011907. http://dx.doi.org/10.1118/1.4845075.
Texte intégral
8
O, Gavrylenko, Zhdanova O, Nazirov R, Parkhomenko D, Shumeyko O et Khalus O. « DETERMINATION OF STATIONARY TANK CAPACITY ACCORDING TO LASER SCAN RESULTS ». National Transport University Bulletin 1, no 51 (2022) : 84–94. http://dx.doi.org/10.33744/2308-6645-2022-1-51-084-094.
Texte intégralRésumé :
At present, many companies and organizations need to store fuel or other liquids for their own needs. The classic option for determining the capacity of tanks is to fill them with liquid, using a liquid quantity meter, the error of which is determined before calibration for a given filling speed. This method is reliable because it all depends on the accuracy of the meter. The principle of operation is simple: a tube with 94 a meter is used to supply liquid to fill the tank to the limit (height) of filling. The value calculated by the meter and is the volume of liquid in the tank. But this method requires a significant amount of time and fluid to conduct the experiment and in practice is not always possible to implement. An alternative is to use a laser scanner to scan the inner surface of the tank. Its volume is calculated on the basis of the obtained arrays of surface points. This article will consider the method of determining the capacity of tanks, which uses the results of laser scanning of the inner surface, and takes into account the geometric characteristics and features of the tank (maximum filling height, maximum depth of depressions, etc.), temperature values during scanning; linear temperature coefficient of expansion of the tank material. KEY WORDS: TANK, CAPACITY, CALIBRATION TABLE, CORRECTION FACTORS, LASER SCANNER.
9
Moon, Seunghwan, Jaekwon Lee, Joho Yun, Juhun Lim, Min-Joo Gwak, Kyung-Su Kim et Jong-Hyun Lee. « Two-Axis Electrostatic Gimbaled Mirror Scanner With Self-Aligned Tilted Stationary Combs ». IEEE Photonics Technology Letters 28, no 5 (1 mars 2016) : 557–60. http://dx.doi.org/10.1109/lpt.2015.2513483.
Texte intégral
10
Alekseev, N. Yu, et P. V. Zyuzin. « Assessment of Applicability of Wi-Fi Analytics in Studies of Urban Public Transport Passenger Flow (Moscow Case Study) ». World of Transport and Transportation 19, no 3 (2 décembre 2021) : 54–66. http://dx.doi.org/10.30932/1992-3252-2021-19-3-6.
Texte intégralRésumé :
The advantages and disadvantages of existing tools for calculating passenger flow are shown using the example of the city of Moscow.The objective of the research was to assess possibilities of using Wi-Fi data as a tool for analysing passenger flow. The authors used two types of Wi-Fi scanners and a tool they developed to analyse the collected data. The primary results of the study demonstrate the possibility of practical application of Wi-Fi data to analyse passenger flow.The described empirical studies, particularly data received from the portable Wi-Fi scanner, have shown that more than 20% of mobile devices in urban public transport and metro are used with Wi-Fi enabled, which is clearly not enough to get results necessary for comprehensive and detailed analysis of passenger flows. Nevertheless, the accumulating data allow to get possibility to forecast general passenger flow.A portable Wi-Fi scanner does not provide an opportunity to extensively capture a large area of the surveyed territory in real time (stops of urban public transport, locations where passengers enter the metro, etc.). Stationary Wi-Fi scanners could increase the amount of data and, accordingly, significantly adjust the results obtained. This enhancement could also be achieved through expansion of adoption of the tool of studying passenger flow to urban railways, i.e., in case of Moscow, to Moscow Central Circle and Moscow Central Diameters, as those routes provide Wi-Fi access at stations and in coaches.Data collected from Wi-Fi scanners can be an additional tool to other data sources, such as validation, automatic systems of passenger flow monitoring, and data obtained from cellular operators. For this reason, the further research in the field of Wi-Fi analytics along with development of technology in the field of existing data sources of passenger flow monitoring may result in better calculation of passenger flow.
11
Xu, P., X. Xing, J. Zheng, S. Chen, Y. Zhang, G. Yuan et M. Sun. « TU-EF-204-04 : Feasibility Study of a Novel Stationary Spectral CT Scanner ». Medical Physics 42, no 6Part34 (juin 2015) : 3620–21. http://dx.doi.org/10.1118/1.4925690.
Texte intégral
12
Prater, C. B. « New tools for Atomic Force Microscopy ». Proceedings, annual meeting, Electron Microscopy Society of America 53 (13 août 1995) : 716–17. http://dx.doi.org/10.1017/s0424820100139950.
Texte intégralRésumé :
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.
13
Patel, Kinjal, et Chaitanya Bhatt. « DEVELOPMENT AND VALIDATION OF A HPTLC METHOD FOR SIMULTANEOUS DENSITOMETRIC ANALYSIS OF GLYCYRRHETIC ACID AND SOLASODINE IN HERBAL DRUG FORMULATION ». International Journal of Current Pharmaceutical Research 9, no 4 (14 juillet 2017) : 29. http://dx.doi.org/10.22159/ijcpr.2017v9i4.20752.
Texte intégralRésumé :
Objective: To develop and validate a simple, precise, selective, and accurate high-performance thin layer chromatographic method for simultaneous densitometric analysis of glycyrrhetic acid and solasodine in the polyherbal formulation.Methods: The method was developed using HPTLC silica gel GF254precoated aluminium plate as the stationary phase and Chloroform: Methanol (9:1 v/v) as the mobile phase. Quantization of glycyrrhetic acid was achieved by determining the area under the curve at 267 nm using CAMAG TLC Scanner and CATS 3 software. Since the structure of solasodine lacks conjugated double bond, it does not give any fluorescence either in the absorbance mode or reflectance mode hence solasodine was derivatized using 0.5%anisaldehyde sulphuric acids which gave a bluish spot as seen on TLC plate. These spots were scanned at 546 nm wavelength using CAMAG TLC Scanner and CATS 3 software.Results: The retention factor for glycyrrhetic acid and solasodine were found to be 0.52±0.01, 0.40±0.01% w/w respectively. The developed HPTLC method was validated using parameters described in International Conference on Harmonization (ICH) guideline. The proposed method showed good linearity in the range of 400-2000 ng spot-1 for glycyrrhetic acid as well as for solasodine. The content of glycyrrhetic acid and solasodine in marketed polyherbal formulation were found to be 0.67%±0.8 and 0.10±0.35%w/w respectively.Conclusion: The developed method can be used as quality control tool for the routine analysis of glycyrrhetic acid and solasodine in polyherbal formulation.
14
Lenk, Peter J., Ambar G. Rao et Vikas Tibrewala. « Nonstationary Conditional Trend Analysis : An Application to Scanner Panel Data ». Journal of Marketing Research 30, no 3 (août 1993) : 288–304. http://dx.doi.org/10.1177/002224379303000302.
Texte intégralRésumé :
Planning and evaluating consumer promotions is facilitated by knowledge of the types of consumers who contribute to incremental sales. In particular, interest may focus on identifying the contributions of buyers segmented on the basis of their prior purchase history. When the distribution of the number of purchase occasions in a base period can be described by the negative binomial distribution (NBD), conditional trend analysis (CTA) is a simple and effective approach for identifying the sources of incremental sales during a test (promotional) period. As currently implemented, CTA assumes a stationary marketing environment. The authors propose an extension of CTA that explicitly incorporates varying marketing activities. They also show that the often observed underprediction of purchases in the test period by nonbuyers in the base period is a consequence of the skewness of the NBD and is not necessarily due to model misspecification. An illustration with scanner panel data is provided.
15
Bechtold, S., et B. Höfle. « HELIOS : A MULTI-PURPOSE LIDAR SIMULATION FRAMEWORK FOR RESEARCH, PLANNING AND TRAINING OF LASER SCANNING OPERATIONS WITH AIRBORNE, GROUND-BASED MOBILE AND STATIONARY PLATFORMS ». ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences III-3 (3 juin 2016) : 161–68. http://dx.doi.org/10.5194/isprsannals-iii-3-161-2016.
Texte intégralRésumé :
In many technical domains of modern society, there is a growing demand for fast, precise and automatic acquisition of digital 3D models of a wide variety of physical objects and environments. Laser scanning is a popular and widely used technology to cover this demand, but it is also expensive and complex to use to its full potential. However, there might exist scenarios where the operation of a <i>real</i> laser scanner could be replaced by a computer simulation, in order to save time and costs. This includes scenarios like teaching and training of laser scanning, development of new scanner hardware and scanning methods, or generation of artificial scan data sets to support the development of point cloud processing and analysis algorithms. To test the feasibility of this idea, we have developed a highly flexible laser scanning simulation framework named <i>Heidelberg LiDAR Operations Simulator (HELIOS)</i>. HELIOS is implemented as a Java library and split up into a core component and multiple extension modules. Extensible Markup Language (XML) is used to define scanner, platform and scene models and to configure the behaviour of modules. Modules were developed and implemented for (1) loading of simulation assets and configuration (i.e. 3D scene models, scanner definitions, survey descriptions etc.), (2) playback of XML survey descriptions, (3) TLS survey planning (i.e. automatic computation of recommended scanning positions) and (4) interactive real-time 3D visualization of simulated surveys. As a proof of concept, we show the results of two experiments: First, a survey planning test in a scene that was specifically created to evaluate the quality of the survey planning algorithm. Second, a simulated TLS scan of a crop field in a precision farming scenario. The results show that HELIOS fulfills its design goals.
16
Bechtold, S., et B. Höfle. « HELIOS : A MULTI-PURPOSE LIDAR SIMULATION FRAMEWORK FOR RESEARCH, PLANNING AND TRAINING OF LASER SCANNING OPERATIONS WITH AIRBORNE, GROUND-BASED MOBILE AND STATIONARY PLATFORMS ». ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences III-3 (3 juin 2016) : 161–68. http://dx.doi.org/10.5194/isprs-annals-iii-3-161-2016.
Texte intégralRésumé :
In many technical domains of modern society, there is a growing demand for fast, precise and automatic acquisition of digital 3D models of a wide variety of physical objects and environments. Laser scanning is a popular and widely used technology to cover this demand, but it is also expensive and complex to use to its full potential. However, there might exist scenarios where the operation of a <i>real</i> laser scanner could be replaced by a computer simulation, in order to save time and costs. This includes scenarios like teaching and training of laser scanning, development of new scanner hardware and scanning methods, or generation of artificial scan data sets to support the development of point cloud processing and analysis algorithms. To test the feasibility of this idea, we have developed a highly flexible laser scanning simulation framework named <i>Heidelberg LiDAR Operations Simulator (HELIOS)</i>. HELIOS is implemented as a Java library and split up into a core component and multiple extension modules. Extensible Markup Language (XML) is used to define scanner, platform and scene models and to configure the behaviour of modules. Modules were developed and implemented for (1) loading of simulation assets and configuration (i.e. 3D scene models, scanner definitions, survey descriptions etc.), (2) playback of XML survey descriptions, (3) TLS survey planning (i.e. automatic computation of recommended scanning positions) and (4) interactive real-time 3D visualization of simulated surveys. As a proof of concept, we show the results of two experiments: First, a survey planning test in a scene that was specifically created to evaluate the quality of the survey planning algorithm. Second, a simulated TLS scan of a crop field in a precision farming scenario. The results show that HELIOS fulfills its design goals.
17
Horáček, Vít, Vitalij Yanovych et Filip Bastl. « Measuring deformations of the fan blade by optical methods ». MATEC Web of Conferences 367 (2022) : 00009. http://dx.doi.org/10.1051/matecconf/202236700009.
Texte intégralRésumé :
Across industries, the demand for the ability to analyze components in operation and make decisions on repair based on the data obtained is growing rapidly. There is the potential to ensure safer operations while saving the cost of unnecessary new parts. A quick and relatively inexpensive method is a 3D scanner - the device that can scan a real component and create an accurate 3D model. For stationary cases - inspecting parts or assemblies - these are already established methods. In contrast, measurement of vibrations and deformations in operation is still not widespread and for turbomachinery, it can be a new direction of development.
18
P. Bhatkande, Apurva, et Prafullchandra Teklae. « HPTLC–densitometric and HPTLC–MS Methods for Analysis of Triterpenoids from Cucurbita maxima Peel ». Journal of Plant Science Research 38, no 2 (10 février 2023) : 717–24. http://dx.doi.org/10.32381/jpsr.2022.38.02.25.
Texte intégralRésumé :
Fruits and vegetables are integral part of our day to day. They are the main source of food for the living system. Large amount of agro-waste generated from food industries and kitchen pertaining to biggest nutritional loss, environmental problems and economical implications. Even though pomace, peels, rind and seeds are considered a waste part of plant they are still rich source of valuable compounds like polyphenols, oils, enzymes, vitamins, fiber, etc. which is just adjunct to its different uses. Present study conducted on waste pumpkin peel. HPTLC fingerprint profile of pumpkin peel methanol extract was performed using HPTLC plate of silica gel 60 F254 as the stationary phase and Toluene: Chloroform: Ethanol (4:4:1 V/V/V) as the mobile phase. After development chromatogram was scanned at 254 nm and 366 nm by densitometric scanner. Anisaldehyde in sulphuric acid is used as a detecting reagent which gives pink-violet and/or giving blue coloration after derivatization of plate. Further HPTLC-MS analysis gives the confirmation to detected terpenoids. Therefore, this waste peel part of the pumpkin can be used in an ingenious way by further purification, isolation and characterization.
19
Shim, Jiyong, Woosung Kim, Duhee Jeon et Hyosung Cho. « Automatic geometry calibration based on metric optimization in stationary computed tomography baggage scanner with 2π-angle sparsity ». Journal of Instrumentation 20, no 03 (1 mars 2025) : C03032. https://doi.org/10.1088/1748-0221/20/03/c03032.
Texte intégralRésumé :
Abstract Recently, SSTLabs Co. in Korea has designed and developed a stationary computed tomography (SCT) baggage scanner with 2π-angle sparsity, comprising 20 pairs of monoblock-type X-ray sources and linear array-type dual-layer detectors arranged within a scan angle of 360∘ at an equiangular distance. We implemented an SCT reconstruction method for a specific (i.e., very sparse-view) system configuration by adopting an iterative algorithm based on the popular compressed-sensing (CS) mathematical theory. However, the method exhibited poor reconstruction quality owing to the mismatch in scan parameters between the nominal (designed) and actual values used during reconstruction. To overcome this limitation, we propose a pragmatic geometric calibration method based on a metric optimization technique for the mean structural similarity index measure to ensure high-quality CS-reconstructed images from the developed SCT baggage scanner. To verify the efficacy of the proposed method, we conducted a numerical simulation and experiments before its practical implementation and found no significant image distortion and edge blur in the SCT images reconstructed with the proposed geometric calibration, except for artifacts stemming from sparse-view angular sampling. The measured signal-to-noise ratio, contrast-to-noise ratio, and mean square error values between the calibrated and corresponding phantom slice images were improved by approximately 5.2-, 7.4-, and 3.5-fold, respectively, compared to those for the uncalibrated images, demonstrating the efficacy of the proposed geometric calibration method. Furthermore, the proposed method is self-operating and thus does not require a geometric calibration phantom.
20
Qudr, Lateef Abd Zaid. « Development of 3D environmental laser scanner using pinhole projection ». Eastern-European Journal of Enterprise Technologies 2, no 1 (110) (20 avril 2021) : 37–43. http://dx.doi.org/10.15587/1729-4061.2021.227629.
Texte intégralRésumé :
Three-dimensional (3D) information of capturing and reconstructing an object existing in its environment is a big challenge. In this work, we discuss the 3D laser scanning techniques, which can obtain a high density of data points by an accurate and fast method. This work considers the previous developments in this area to propose a developed cost-effective system based on pinhole projection concept and commercial hardware components taking into account the current achieved accuracy. A laser line auto-scanning system was designed to perform close-range 3D reconstructions for home/office objects with high accuracy and resolution. The system changes the laser plane direction with a microcontroller to perform automatic scanning and obtain continuous laser strips for objects’ 3D reconstruction. The system parameters were calibrated with Matlab’s built-in camera calibration toolbox to find camera focal length and optical center constraints. The pinhole projection equation was defined to optimize the prototype rotating axis equation. The developed 3D environmental laser scanner with pinhole projection proved the system’s effectiveness on close-range stationary objects with high resolution and accuracy with a measurement error in the range (0.05–0.25) mm. The 3D point cloud processing of the Matlab computer vision toolbox has been employed to show the 3D object reconstruction and to perform the camera calibration, which improves efficiency and highly simplifies the calibration method. The calibration error is the main error source in the measurements, and the errors of the actual measurement are found to be influenced by several environmental parameters. The presented platform can be equipped with a system of lower power consumption, and compact smaller size
21
Nikoohemat, S., A. Diakité, S. Zlatanova et G. Vosselman. « INDOOR 3D MODELING AND FLEXIBLE SPACE SUBDIVISION FROM POINT CLOUDS ». ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences IV-2/W5 (29 mai 2019) : 285–92. http://dx.doi.org/10.5194/isprs-annals-iv-2-w5-285-2019.
Texte intégralRésumé :
<p><strong>Abstract.</strong> Indoor navigation can be a tedious process in a complex and unknown environment. It gets more critical when the first responders try to intervene in a big building after a disaster has occurred. For such cases, an accurate map of the building is among the best supports possible. Unfortunately, such a map is not always available, or generally outdated and imprecise, leading to error prone decisions. Thanks to advances in the laser scanning, accurate 3D maps can be built in relatively small amount of time using all sort of laser scanners (stationary, mobile, drone), although the information they provide is generally an unstructured point cloud. While most of the existing approaches try to extensively process the point cloud in order to produce an accurate architectural model of the scanned building, similar to a Building Information Model (BIM), we have adopted a space-focused approach. This paper presents our framework that starts from point-clouds of complex indoor environments, performs advanced processes to identify the 3D structures critical to navigation and path planning, and provides fine-grained navigation networks that account for obstacles and spatial accessibility of the navigating agents. The method involves generating a volumetric-wall vector model from the point cloud, identifying the obstacles and extracting the navigable 3D spaces. Our work contributes a new approach for space subdivision without the need of using laser scanner positions or viewpoints. Unlike 2D cell decomposition or a binary space partitioning, this work introduces a space enclosure method to deal with 3D space extraction and non-Manhattan World architecture. The results show more than 90% of spaces are correctly extracted. The approach is tested on several real buildings and relies on the latest advances in indoor navigation.</p>
22
Matsusaka, Yohji, Rudolf A. Werner, Paula Arias-Loza, Naoko Nose, Takanori Sasaki, Xinyu Chen, Constantin Lapa et Takahiro Higuchi. « Performance Evaluation of a Preclinical SPECT Scanner with a Collimator Designed for Medium-Sized Animals ». Molecular Imaging 2022 (16 juillet 2022) : 1–9. http://dx.doi.org/10.1155/2022/9810097.
Texte intégralRésumé :
Background. Equipped with two stationary detectors, a large bore collimator for medium-sized animals has been recently introduced for dedicated preclinical single-photon emission computed tomography (SPECT) imaging. We aimed to evaluate the basic performance of the system using phantoms and healthy rabbits. Methods. A general-purpose medium-sized animal (GP-MSA) collimator with 135 mm bore diameter and thirty-three holes of 2.5 mm diameter was installed on an ultrahigh-resolution scanner equipped with two large stationary detectors (U-SPECT5-E/CT). The sensitivity and uniformity were investigated using a point source and a cylinder phantom containing 99mTc-pertechnetate, respectively. Uniformity (in %) was derived using volumes of interest (VOIs) on images of the cylinder phantom and calculated as maximum count − minimum count / maximum count + minimum count × 100 , with lower values of % indicating superior performance. The spatial resolution and contrast-to-noise ratios (CNRs) were evaluated with images of a hot-rod Derenzo phantom using different activity concentrations. Feasibility of in vivo SPECT imaging was finally confirmed by rabbit imaging with the most commonly used clinical myocardial perfusion SPECT agent [99mTc]Tc-sestamibi (dynamic acquisition with a scan time of 5 min). Results. In the performance evaluation, a sensitivity of 790 cps/MBq, a spatial resolution with the hot-rod phantom of 2.5 mm, and a uniformity of 39.2% were achieved. The CNRs of the rod size 2.5 mm were 1.37, 1.24, 1.20, and 0.85 for activity concentration of 29.2, 1.0, 0.5, and 0.1 MBq/mL, respectively. Dynamic SPECT imaging in rabbits allowed to visualize most of the thorax and to generate time-activity curves of the left myocardial wall and ventricular cavity. Conclusion. Preclinical U-SPECT5-E/CT equipped with a large bore collimator demonstrated adequate sensitivity and resolution for in vivo rabbit imaging. Along with its unique features of SPECT molecular functional imaging is a superior collimator technology that is applicable to medium-sized animal models and thus may promote translational research for diagnostic purposes and development of novel therapeutics.
23
Joshi, Shraddha, Varsha M. Jadhav et Vilasrao J. Kadam. « Analytical method development and its validation for simultaneous estimation of catechin and curcumin by HPTLC from ancho lean tablets ». Indian Journal of Pharmaceutical and Biological Research 6, no 02 (30 juin 2018) : 23–30. http://dx.doi.org/10.30750/ijpbr.6.2.5.
Texte intégralRésumé :
HPTLC method which is simple, particular and robust has been developed for the simultaneous estimation of Catechin and Curcumin from an Ayurvedic formulation. The method was validated using parameters such as linearity, specificity, and precision, limit of quantification (LOQ), limit of detection (LOD), accuracy and robustness as per ICH guidelines. The present work deals with development of HPTLC method for simultaneous estimation of catechin and curcumin in marketed Ayurvedic formulations. Chromatographic separation of the drugs was performed on Merck TLC aluminium plates pre-coated with silica gel 60F254 as the stationary phase. The mobile phase selected was toluene:ethyl acetate: formic acid (7: 2.5: 0.5 v/v/v). The sample solutions were prepared in methanol and linear ascending development was carried out in twin trough glass chamber and scanned at 269 nm using Camag TLC scanner. The two markers were resolved successfully with Rf values 0.23±0.02 and 0.58±0.02 for catechin and curcumin, respectively. The regression analysis data indicated good linear relationship for the calibration plots for Catechin and Curcumin in the range of 1900-2500 ng/spot and 200-800 ng/spot and regression coefficient was 0.990 and 0.997 respectively. The proposed method can be used for the estimation of these markers in combined Ayurvedic formulation.
24
Shim, J., D. Jeon, Y. Jung, H. Yang, Y. Lim, H. Cho, C. Seo, K. Y. Choi, C. S. Sone et M. S. Jang. « Design of stationary computed tomography baggage scanner with π-angle sparsity and compressed-sensing reconstruction : simulation study ». Journal of Instrumentation 18, no 01 (1 janvier 2023) : C01058. http://dx.doi.org/10.1088/1748-0221/18/01/c01058.
Texte intégralRésumé :
Abstract Continuing our research on X-ray R&D for aviation security, we designed a novel stationary computed tomography (SCT) baggage scanner with π-angle sparsity, comprising several dozen pairs of nanotube-based X-ray source and linear array-type detector placed within a scan angle of 180° at an equiangular distance. Simultaneously, we developed a reconstruction method for the specific configuration adopting an iterative algorithm based on the popular compressed-sensing (CS) scheme. To validate the efficacy of the proposed SCT design, we conducted a series of simulations using a numerical baggage phantom before its practical implementation. The results showed that the proposed SCT design and corresponding reconstruction method significantly reduced the streak artifacts appearing in the filtered-backprojection (FBP) reconstruction, thereby considerably improving the image quality. The contrast-to-noise ratio evaluated under a test condition of 180°/P20/CS was approximately 16.2, approximately 4.7 and 1.1 times larger than those for 360°/P20/FBP and 360°/P20/CS, respectively. The proposed SCT design enables saving scan time, improving image quality, and restricting radiation exposure zone.
25
Hofstetter, Louis, Yvonne Naegelin, Lukas Filli, Pascal Kuster, Stefan Traud, Renata Smieskova, Nicole Mueller-Lenke et al. « Progression in disability and regional grey matter atrophy in relapsing–remitting multiple sclerosis ». Multiple Sclerosis Journal 20, no 2 (26 juin 2013) : 202–13. http://dx.doi.org/10.1177/1352458513493034.
Texte intégralRésumé :
Background: In multiple sclerosis (MS) regional grey matter (GM) atrophy has been associated with disability progression. Objective: The aim of this study was to compare regional GM volume changes in relapsing–remitting MS (RRMS) patients with progressive and stable disability, using voxel-based morphometry (VBM). Methods: We acquired baseline and 1-year follow-up 3-dimensional (3D) T1-weighted magnetic resonance imaging (MRI) data of RRMS patients, using two 1.5-Tesla scanners. Patients were matched pair-wise with respect to age, gender, disease duration, medication, scanner and baseline Expanded Disability Status Scale (EDSS) into 13 pairs, with either progressive EDSS (≥ 1 point change y-1) or stable EDSS, as well as into 29 pairs with either progressive Multiple Sclerosis Functional Composite (MSFC) at ≥ 0.25% decrease in y-1 in any component, or stable MSFC. We analysed longitudinal regional differences in GM volumes in the progressive and stable EDSS and MSFC groups, respectively, using VBM. Results: Significant GM volume reductions occurred in the right precuneus, in the progressive EDSS group. Differential between-group effects occurred in the right precuneus and in the postcentral gyrus. Further longitudinal GM volume reductions occurred in the right orbicular gyrus, in the progressive MSFC group, but no between-group differences were observed (non-stationary cluster-wise inference, all Pcorrected < 0.05). Conclusion: These results suggested a direct association of disability progression and regional GM atrophy in RRMS.
26
Shim, J., D. Jeon, Y. Jung, H. Yang, Y. Lim, H. Cho, C. Seo, K. Y. Choi, C. S. Sone et M. S. Jang. « Erratum : Design of stationary computed tomography baggage scanner with π-angle sparsity and compressed-sensing reconstruction : simulation study ». Journal of Instrumentation 19, no 07 (1 juillet 2024) : E07003. http://dx.doi.org/10.1088/1748-0221/19/07/e07003.
Texte intégral
27
Shim, Jiyong, Youngjo Kim, Hyesun Yang, Hyosung Cho et Kwangyun Choi. « Implementation of dual-energy material decomposition technique in stationary CT baggage scanner withπ-angle sparsity for enhancing threat detection ». Journal of Instrumentation 18, no 11 (1 novembre 2023) : C11003. http://dx.doi.org/10.1088/1748-0221/18/11/c11003.
Texte intégralRésumé :
Abstract Two-dimensional X-ray inspection systems are widely used in aviation security applications; however, they have inherent limitations in recognizing the three-dimensional (3D) shapes of hidden objects. Therefore, there is a growing demand for the implementation of advanced 3D X-ray inspection systems at airports for more accurate detection of threats in luggage and personal belongings. In this study, we designed a new stationary computed tomography (CT) baggage scanner with π-angle sparsity (i.e., 20 pairs of X-ray sources and line detectors were placed within a scan angle of 180°) and compressed sensing (CS)-based reconstruction, and implemented a dual-energy material decomposition (DEMD) technique in the proposed system to separate soft and dense materials of an examined object to enhance threat detection. To validate the efficacy of the proposed approach (CS/180°/P20), we conducted a feasibility study using numerical simulation before its practical implementation. Polychromatic projections were emulated at X-ray tube voltages of 60 and 140 kVp, and DEMD was applied to the projections prior to CT reconstruction. Conventional and dual-energy CT images were reconstructed using both standard filtered-backprojection (FBP) and state-of-the-art CS-based algorithms to compare the image quality. According to our simulation results, the CS-reconstructed images were almost unaffected by the clearly evident streak artifacts on the FBP-reconstructed images because of the use of 20 extreme sparse-view projections, and the image quality of the dual-energy CT images obtained using the proposed CT configuration was similar to that obtained using the conventional CT configuration with 720 dense projections, indicating the efficacy of the proposed approach. Consequently, high-quality dual-energy CT images of soft and dense materials were successfully obtained using the proposed stationary CT configuration.
28
Barba, S., A. di Filippo, M. Limongiello et B. Messina. « INTEGRATION OF ACTIVE SENSORS FOR GEOMETRIC ANALYSIS OF THE CHAPEL OF THE HOLY SHROUD ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W15 (20 août 2019) : 149–56. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w15-149-2019.
Texte intégralRésumé :
<p><strong>Abstract.</strong> The digital acquisition of Cultural Heritage is a complex process, highly depending on the nature of the object as well as the purpose of its detection. Even if there are different survey techniques and sensors that allow the generation of realistic 3D models, defined by a good metric quality and a detail consistent with the geometric characteristics of the object, an interesting goal could be to develop a unified treatment of the methodologies. The Chapel of the Holy Shroud, with its intricate articulation, becomes the benchmark to test an integrated protocol between a terrestrial laser scanner (TLS) and a wearable mobile laser system (WMLS) based on a SLAM approach. In order to quantify the accuracy and precision of the latter solution, several forms of comparison are proposed. For the case study the ZEB-REVO, produced and marketed by GeoSLAM, is tested. Computations of cloud-to-cloud (C2C) absolute distances, comparisons of slices and extractions of planar features are performed, using stationary laser scanner (Faro Focus<sup>S</sup> S350) as a reference. Finally, the obtained results are reported, allowing us to assert that the quality of the WMLS measurements is compatible with the data provided by the manufacturer, thus making the instrumentation suitable for certain specific applications.</p>
29
Kermarrec, Gaël. « On Estimating the Hurst Parameter from Least-Squares Residuals. Case Study : Correlated Terrestrial Laser Scanner Range Noise ». Mathematics 8, no 5 (29 avril 2020) : 674. http://dx.doi.org/10.3390/math8050674.
Texte intégralRésumé :
Many signals appear fractal and have self-similarity over a large range of their power spectral densities. They can be described by so-called Hermite processes, among which the first order one is called fractional Brownian motion (fBm), and has a wide range of applications. The fractional Gaussian noise (fGn) series is the successive differences between elements of a fBm series; they are stationary and completely characterized by two parameters: the variance, and the Hurst coefficient (H). From physical considerations, the fGn could be used to model the noise of observations coming from sensors working with, e.g., phase differences: due to the high recording rate, temporal correlations are expected to have long range dependency (LRD), decaying hyperbolically rather than exponentially. For the rigorous testing of deformations detected with terrestrial laser scanners (TLS), the correct determination of the correlation structure of the observations is mandatory. In this study, we show that the residuals from surface approximations with regression B-splines from simulated TLS data allow the estimation of the Hurst parameter of a known correlated input noise. We derive a simple procedure to filter the residuals in the presence of additional white noise or low frequencies. Our methodology can be applied to any kind of residuals, where the presence of additional noise and/or biases due to short samples or inaccurate functional modeling make the estimation of the Hurst coefficient with usual methods, such as maximum likelihood estimators, imprecise. We demonstrate the feasibility of our proposal with real observations from a white plate scanned by a TLS.
30
Leitner, Bohuš, Martin Decký et Matúš Kováč. « ROAD PAVEMENT LONGITUDINAL EVENNESS QUANTIFICATION AS STATIONARY STOCHASTIC PROCESS ». Transport 34, no 3 (27 février 2019) : 193–203. http://dx.doi.org/10.3846/transport.2019.8577.
Texte intégralRésumé :
One of the requirements concerning pavement quality is the evenness of its surface. Pavement unevenness has a random character and has an adverse influence to rolling resistance, tyre–pavement coherence, safety and the driving comfort. Knowledge of “longitudinal unevenness” has been long recognized as an important criteria of road performance, not only for safety by causing vehicle vibrations and affecting ride comfort but also as a major factor in pavement deterioration and working conditions of vehicles. The paper presents two original devices for the measurement of pavement longitudinal unevenness designed as a reaction to results and experiences gathered from a few years’ research activities, measurements and evaluations of road pavement evenness carried out in the authors' work place (University of Žilina – UNIZA). The first equipment has been designed as a single-wheel trailing vehicle and has been constructed on the Double-mass Measuring Set (DMS) principle and it is referred to as UNIZA single-wheel vehicle JP VSDS. The main reason for designing the device were authors’ findings that the reference quarter car model (used for calculation of International Roughness Index – IRI) can provide evaluation, which can be in contradiction with ride safety. This fact is determined by overvaluation of the short wavelengths and undervaluation the longer wavelengths by reference model. The second one is a profiler with very high resolution of surface scanning using mathematical models for unevenness evaluation. The device is referred to as Dynamic Road Scanner (DRS). The reason for designing of this equipment was in the first place insufficient repeatability of transversal unevenness measurements of device used by Slovak Road Administration, but for the purpose of correctness and measurements accuracy verifying were also results of longitudinal unevenness measurements compared. The paper presents results of evaluation by international established dynamic quantifiers of longitudinal unevenness based on measurements performed by these devices on three selected road sections in Slovakia. In the next part of the paper are compared IRI values obtained by mathematical calculations using reference quarter car model “driving” on road section profile measured by geodetic survey with IRI values obtained by conversion of the unevenness degree C (measured by UNIZA single-wheel vehicle JP VSDS) and IRI values measured by profilometer DRS.
31
Lu, Jing, Hong-yan Ma, Wei Zhang, Zhi-guo Ma et Shun Yao. « Separation of Berberine Hydrochloride and Tetrahydropalmatine and Their Quantitative Analysis with Thin Layer Chromatography Involved with Ionic Liquids ». Journal of Analytical Methods in Chemistry 2015 (2015) : 1–7. http://dx.doi.org/10.1155/2015/642401.
Texte intégralRésumé :
[BMIM]OH was used in mobile and stationary phase of thin layer chromatography (TLC) to analyze berberine hydrochloride and tetrahydropalmatine for the first time. Supported imidazole ionic liquid with hydroxide ion on silica gel (SiO2·Im+·OH−) was synthesized through simple procedure and characterized by Fourier transform infrared spectroscopy (FT-IR), elemental analysis, and scanning electron microscope (SEM). Moreover, on the plates prepared by SiO2·Im+·OH−, the contents of the above alkaloids in the Chinese patent medicine (CPM) of “Stomacheasy” capsule were successfully determined by TLC scanner. The key conditions and chromatographic behaviors were also investigated in detail. According to similar ways, ionic liquids (ILs) also can be used in other planar chromatographies in two modes. This study is expected to be helpful in expanding the application of IL and its bonded silica gel in TLC separation field.
32
Scharmann, Steffen, Konstantin Keil, Jana Zorn, Patrick Dietz, Benny Nauschütt, Kristof Holste, Klaus Hannemann et al. « Thrust measurement of an ion thruster by a force probe approach and comparison to a thrust balance ». AIP Advances 12, no 4 (1 avril 2022) : 045218. http://dx.doi.org/10.1063/5.0066401.
Texte intégralRésumé :
A key parameter when characterizing the performance of an electric propulsion system is obviously its thrust. The thrust can be either determined directly using a so-called thrust balance or deduced from indirect measurements. Here, we present a comparison of thrust measurements of the same radio frequency ion thruster in the thrust range from 250 μN to 1.5 mN using three different approaches: a conventional direct measurement employing a thrust balance and two indirect measurements, one based on a force probe located stationary in the thruster’s plume in conjunction with a scan of the ion beam profile using a Faraday-array scanner, and another one based on a measurement of the beam current at the grid system and a correction for beam divergence deduced from the Faraday-array scans. The results of the three approaches are compared for different beam currents, and pros and cons of the approaches are discussed.
33
Freitas, Renato P. de, Miguel A. de Oliveira, Matheus B. de Oliveira, André R. Pimenta, Valter de S. Felix, Marcelo O. Pereira, Elicardo A. S. Gonçalves et al. « Development of a Macro X-ray Fluorescence (MA-XRF) Scanner System for In Situ Analysis of Paintings That Operates in a Static or Dynamic Method ». Quantum Beam Science 8, no 4 (17 octobre 2024) : 26. http://dx.doi.org/10.3390/qubs8040026.
Texte intégralRésumé :
This work presents the development of a macro X-ray fluorescence (MA-XRF) scanner system for in situ analysis of paintings. The instrument was developed to operate using continuous acquisitions, where the module with the X-ray tube and detector moves at a constant speed, dynamically collecting spectra for each pixel of the artwork. Another possible configuration for the instrument is static acquisitions, where the module with the X-ray tube and detector remains stationary to acquire spectra for each pixel. The work also includes the analytical characterization of the system, which incorporates a 1.00 mm collimator that allows for a resolution of 1.76 mm. Additionally, the study presents the results of the analysis of two Brazilian paintings using this instrument. The elemental maps obtained enabled the characterization of the pigments used in the creation of the artworks and materials used in restoration processes.
34
Tkáč, Matúš, et Peter Mésároš. « TERRESTRIAL LASER SCANNING – POINT CLOUD IN BUILDING CONSTRUCTION ». Czech Journal of Civil Engineering 2, no 2 (31 décembre 2016) : 156–61. http://dx.doi.org/10.51704/cjce.2016.vol2.iss2.pp156-161.
Texte intégralRésumé :
3D laser scanner refers to terrestrial (stationary), mobile (vehicle-mounted), or aerial (aircraftmounted) scanning devices. Terrestrial Laser Scanning (TLS) is increasingly used in the Architectural, Engineering, Construction and Facilities Management industry (AEC&FM) due to the significant performance improvements that it can support. TLS is a modern technology that is revolutionizing surveying works. One of the key advantages of laser scanning is the ability to quickly obtain large amounts of data in a short time. The result of laser scanning is a point cloud. Point cloud is essentially a three-dimensional (3D) imaging system which is used for the digital representation of the existing respectively of the real state of building objects. Point cloud has in building construction a very wide application. The aim of this article is explain what is TLS, what is a point cloud and describe how to use him in different areas of building construction.
35
Jun, Min-Ho, Seunghwan Moon, Byeong Ha Lee et Jong-Hyun Lee. « A gimbal-less two-axis electrostatic scanner with tilted stationary vertical combs and serially connected springs via a microassembly process ». Journal of Micromechanics and Microengineering 24, no 9 (6 août 2014) : 095008. http://dx.doi.org/10.1088/0960-1317/24/9/095008.
Texte intégral
36
Lubberink, Mark, Tsuyoshi Kosugi, Harald Schneider, Hiroyuki Ohba et Mats Bergström. « Non-stationary convolution subtraction scatter correction with a dual-exponential scatter kernel for the Hamamatsu SHR-7700 animal PET scanner ». Physics in Medicine and Biology 49, no 5 (13 février 2004) : 833–42. http://dx.doi.org/10.1088/0031-9155/49/5/013.
Texte intégral
37
Kang, Jitong, Mei Li, Shanjun Mao, Yingbo Fan, Zheng Wu et Ben Li. « A Coal Mine Tunnel Deformation Detection Method Using Point Cloud Data ». Sensors 24, no 7 (4 avril 2024) : 2299. http://dx.doi.org/10.3390/s24072299.
Texte intégralRésumé :
In recent years, the deformation detection technology for underground tunnels has played a crucial role in coal mine safety management. Currently, traditional methods such as the cross method and those employing the roof abscission layer monitoring instrument are primarily used for tunnel deformation detection in coal mines. With the advancement of photogrammetric methods, three-dimensional laser scanners have gradually become the primary method for deformation detection of coal mine tunnels. However, due to the high-risk confined spaces and distant distribution of coal mine tunnels, stationary three-dimensional laser scanning technology requires a significant amount of labor and time, posing certain operational risks. Currently, mobile laser scanning has become a popular method for coal mine tunnel deformation detection. This paper proposes a method for detecting point cloud deformation of underground coal mine tunnels based on a handheld three-dimensional laser scanner. This method utilizes SLAM laser radar to obtain complete point cloud information of the entire tunnel, while projecting the three-dimensional point cloud onto different planes to obtain the coordinates of the tunnel centerline. By using the calculated tunnel centerline, the three-dimensional point cloud data collected at different times are matched to the same coordinate system, and then the tunnel deformation parameters are analyzed separately from the global and cross-sectional perspectives. Through on-site collection of tunnel data, this paper verifies the feasibility of the algorithm and compares it with other centerline fitting and point cloud registration algorithms, demonstrating higher accuracy and meeting practical needs.
38
Wikara, Tina, Anny Sulistiowaty, Sri Murhandini et Tepy Usia. « Fingerprint Study of Curcuma xanthorrhiza Rhizome by High Performance Thin Layer Chromatography (HPTLC) ». Jurnal Jamu Indonesia 1, no 2 (30 septembre 2016) : 9–14. http://dx.doi.org/10.29244/jji.v1i2.13.
Texte intégralRésumé :
The rhizome of Curcuma xanthorrhiza Roxb is intensively used in Indonesia as traditional medicine. It is widely used for hepatoprotective and anti inflammatory activities. To ensure the quality of its extract, we have studied the fingerprint or phytochemical analysis. This research was aimed to produce a chromatogram profile of the rhizome by HPTLC. The HPTLC fingerprint chromatogram of C. xanthorrhiza rhizome was performed using HPTLC plate of silica gel 60 F254 as the stationary phase and chloroform-methanol (97:3) as the mobile phase. Spot detection was carried out by TLC photo documentary system at 254 and 366 nm and TLC scanner at 427 nm. The developed method was validated according to ICH guidelines by determination of specificity and precision. We found that the specifity and precission of the method were met the acceptance criteria. In conclusion, the developed method is valid and could be used for quality control and standardization of herbal medicine containing C. xanthorrhiza rhizome.
39
Wikara, Tina, Anny Sulistiowaty, Sri Murhandini et Tepy Usia. « Fingerprint Study of Curcuma xanthorrhiza Rhizome by High Performance Thin Layer Chromatography (HPTLC) ». Jurnal Jamu Indonesia 1, no 2 (30 septembre 2016) : 9–14. http://dx.doi.org/10.29244/jjidn.v1i2.30607.
Texte intégralRésumé :
The rhizome of Curcuma xanthorrhiza Roxb is intensively used in Indonesia as traditional medicine. It is widely used for hepatoprotective and anti inflammatory activities. To ensure the quality of its extract, we have studied the fingerprint or phytochemical analysis. This research was aimed to produce a chromatogram profile of the rhizome by HPTLC. The HPTLC fingerprint chromatogram of C. xanthorrhiza rhizome was performed using HPTLC plate of silica gel 60 F254 as the stationary phase and chloroform-methanol (97:3) as the mobile phase. Spot detection was carried out by TLC photo documentary system at 254 and 366 nm and TLC scanner at 427 nm. The developed method was validated according to ICH guidelines by determination of specificity and precision. We found that the specifity and precission of the method were met the acceptance criteria. In conclusion, the developed method is valid and could be used for quality control and standardization of herbal medicine containing C. xanthorrhiza rhizome.
40
Смолин et V. Smolin. « Mathematical Simulation of Biotechnical Scanner to Determine Hydration Degrees a Biological Tissue in Norme and at Different Pathologies ». Journal of New Medical Technologies 22, no 1 (11 février 2015) : 11–16. http://dx.doi.org/10.12737/9068.
Texte intégralRésumé :
The organs and tissues of the living body depending on the structure and functional states can contain from 50 to 90% of water. Water in a living organism can be in two forms: free water and structured water. Structured water forms strong links with organic molecules. Free water is movable, its quantity can vary considerably depending on the functional state of the body and determines a hydration degree of a tissues.
In clinical practice, the existing technical possibilities of determining hydration degree of biological objects are li-mited and hardly used. Any conclusions about the cause of death due to swelling are not sufficiently and quantified justified.
This paper is devoted to the development of a mathematical model of biotechnical scanner to determine the degree of hydration of biological tissues, based on the physic-chemical effect caused by additive volume of the system in the interaction of the sample of biological tissue with ethanol.
The mathematical model demonstrated that the violations of additivity volume are observed even with the addition of small water volume to large alcohol volume. A probabilistic model was developed and shown that the effects of the exothermic reaction, mixing water and ethanol, have a strong effect on the dates of the process. But this fixing process of a biological object is extended during times, the studied system by the end of fixation will go down in the stationary regime, which will determine the degree of hydration.
Registration changes of the system volume during the interaction of a biological object with ethanol allows to studying the dynamics of physical and chemical processes in the reactor of biotechnical scanner.
41
Rahmiyani, Ira, Anna Yuliana, Dea Helyani Rukmana, Lilis Tuslinah et Vera Nurviana. « α-Mangostin Content of Mangosteen Leaves (Garcinia mangostana L.) Based on Different Growing Conditions ». PLANTA TROPIKA 11, no 2 (18 septembre 2023) : 160–67. http://dx.doi.org/10.18196/pt.v11i2.16848.
Texte intégralRésumé :
Environmental factors, such as soil height, plant age, soil conditions, maintenance, and plant seeds influence the content of secondary metabolites in an organism. The growing conditions can also affect the content of active compounds in plants. Xanthone is an active compound in Garcinia mangostana Linn. One of its derivatives is α-mangostin, which has antioxidant, anticancer, antituberculosis and antihistamine effects. This study aimed to determine the effects of growing conditions on the levels of α-mangosteen in mangosteen leaf extract using Thin Layer Chromatography-Densitometry. Standard solution of α-mangosteen and ethyl acetate extract of mangosteen leaves (A and B samples) were analyzed with Camag TLC Scanner 3 using silica gel 60 F254 stationary phase and chloroform-ethyl acetate mobile phase (9:1). The results showed that the Rf values for standard solution of α-mangostin, sample A, and sample B were 0.65, 0.62, and 0.62, respectively. Meanwhile, the levels obtained from samples A and B were 2.10% ± 0.0755 and 2.07% ± 0.0321, respectively. Different growing conditions did not affect the level of α-mangostin ethyl acetate extract of mangosteen leaves.
42
Lachmayer, L., T. Recker, G. Dielemans, K. Dörfler et A. Raatz. « AUTONOMOUS SENSING AND LOCALIZATION OF A MOBILE ROBOT FOR MULTI-STEP ADDITIVE MANUFACTURING IN CONSTRUCTION ». International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B1-2022 (30 mai 2022) : 453–58. http://dx.doi.org/10.5194/isprs-archives-xliii-b1-2022-453-2022.
Texte intégralRésumé :
Abstract. In contrast to stationary systems, mobile robots have an arbitrarily expandable workspace. As a result, the spatial dimensioning of the task to be mastered plays only a subordinate role and can be scaled as desired. For the construction industry in particular, which requires the handling and production of substantial components, mobile robots mean an unlimited expansion of the workspace based on their mobility levels and thus increased flexibility. The greatest challenge in mobile robotics lies with the discrepancy between the precision required for the task and the achievable positioning accuracy. External localization systems show significant potential for improvement in this respect but, in many cases, require a line of sight between the measurement system and the robot or a time-consuming calibration of markers. Therefore, this article presents an approach for an onboard localization system for use in a multi-step additive manufacturing processes for building construction. While a SLAM algorithm is used for the initial estimation of the robot’s base at the work site, in a refined estimation step, the positioning accuracy is enhanced using a 2D-laser-scanner. This 2D-scanner is used to create a 3D point cloud of the 3D-printed component each time after a print job of one segment has been carried out and before continuing a print job from a new location, to enable printing of layers on top of each other with sufficient accuracy over many repositioning manouvres. When the robot returns to a position for print continuation, the initial and the new point clouds are compared using an ICP-algorithm, and the resulting transformation is used to refine the robot’s pose estimation relative to the 3D-printed building component. While initial experiments demonstrate the approach’s potential, transferring it to large-scale 3D-printed components presents additional challenges, highlighted in this paper.
43
Galeev, R. M., N. E. Berdnikova, I. M. Berdnikov et A. B. Spasibko. « Experience of Reconstructing the Appearance of an Early Neolithic Human from a Burial at the Shumilikha Cemetery (Southern Angara Region) ». Bulletin of the Irkutsk State University. Geoarchaeology, Ethnology, and Anthropology Series 41 (2022) : 122–31. http://dx.doi.org/10.26516/2227-2380.2022.41.12.
Texte intégralRésumé :
This paper presents the results of a reconstruction of the appearance of a hunter-gatherer of the Kitoi culture from a burial at the Shumilikha cemetery in the Southern Angara region. The excavations were carried out in 1999. In the grave, the walls of which were coated with clay, the remains of a human 25–35 years old were found. Under the skeleton, which was sprinkled with “ocher” (grated hematite rock), traces of a wooden construction were recorded. The grave goods (more than a hundred items) included such interesting finds as the kernels of fishhooks, a bone spoon, beads made of bone paste, as well as two items made of white jade: a ring and a cylindrical bead. There is a reliable radiocarbon date for the human bone, which, taking into account the correction for the reservoir effect, shows an age of 7,003±106 cal BP and allows you to determine the age of this complex by the Early Neolithic. Modern software for 3D modeling and visualization opens up great opportunities, so a virtual method was chosen to reconstruct the appearance of a human from a burial. First, all the bones of the skeleton were scanned, for which two types of 3D equipment were used: a stationary scanner RangeVision Spectrum based on structured light photogrammetry (for the skull and small bones) and a hybrid handheld scanner with structured LED and infrared illumination Shining 3D Einscan H (for large bones). The scan results are processed in RangeVision's ScanCenter NG using built-in algorithms. Filling voids, smoothing surfaces, simplifying 3D models, and correcting mesh defects are done manually at the stage of model postprocessing. For further work, the resulting models were transferred to the stl format. Facial reconstruction was carried out in Blender and ZBrush in several stages: 1) importing and combining models; 2) modeling of lost teeth and reconstruction of the occlusion; 3) CAD modeling of a set of soft tissue depth markers and their positioning by craniometric points; 4) modeling of auxiliary circuits for nose reconstruction and eyeball setting; 5) modeling of masticatory muscles; 6) modeling of facial muscles and fat sacs to simplify the production of a basic head model; 7) modeling the base mesh of the head; 8) digital sculpting of the head; 9) detailing of the digital sculpture; 10) rendering of the model and preparing the model for printing. As a result, a digital model of the appearance of an Early Neolithic hunter-gatherer from a burial at the Shumilikha cemetery was obtained.
44
Galeev, R. M., N. E. Berdnikova, I. M. Berdnikov et A. B. Spasibko. « Experience of Reconstructing the Appearance of an Early Neolithic Human from a Burial at the Shumilikha Cemetery (Southern Angara Region) ». Bulletin of the Irkutsk State University. Geoarchaeology, Ethnology, and Anthropology Series 41 (2022) : 122–31. http://dx.doi.org/10.26516/2227-2380.2022.41.122.
Texte intégralRésumé :
This paper presents the results of a reconstruction of the appearance of a hunter-gatherer of the Kitoi culture from a burial at the Shumilikha cemetery in the Southern Angara region. The excavations were carried out in 1999. In the grave, the walls of which were coated with clay, the remains of a human 25–35 years old were found. Under the skeleton, which was sprinkled with “ocher” (grated hematite rock), traces of a wooden construction were recorded. The grave goods (more than a hundred items) included such interesting finds as the kernels of fishhooks, a bone spoon, beads made of bone paste, as well as two items made of white jade: a ring and a cylindrical bead. There is a reliable radiocarbon date for the human bone, which, taking into account the correction for the reservoir effect, shows an age of 7,003±106 cal BP and allows you to determine the age of this complex by the Early Neolithic. Modern software for 3D modeling and visualization opens up great opportunities, so a virtual method was chosen to reconstruct the appearance of a human from a burial. First, all the bones of the skeleton were scanned, for which two types of 3D equipment were used: a stationary scanner RangeVision Spectrum based on structured light photogrammetry (for the skull and small bones) and a hybrid handheld scanner with structured LED and infrared illumination Shining 3D Einscan H (for large bones). The scan results are processed in RangeVision's ScanCenter NG using built-in algorithms. Filling voids, smoothing surfaces, simplifying 3D models, and correcting mesh defects are done manually at the stage of model postprocessing. For further work, the resulting models were transferred to the stl format. Facial reconstruction was carried out in Blender and ZBrush in several stages: 1) importing and combining models; 2) modeling of lost teeth and reconstruction of the occlusion; 3) CAD modeling of a set of soft tissue depth markers and their positioning by craniometric points; 4) modeling of auxiliary circuits for nose reconstruction and eyeball setting; 5) modeling of masticatory muscles; 6) modeling of facial muscles and fat sacs to simplify the production of a basic head model; 7) modeling the base mesh of the head; 8) digital sculpting of the head; 9) detailing of the digital sculpture; 10) rendering of the model and preparing the model for printing. As a result, a digital model of the appearance of an Early Neolithic hunter-gatherer from a burial at the Shumilikha cemetery was obtained.
45
Bloemberg, Jette, Bruce Hoppener, Bram Coolen, Aimée Sakes et Paul Breedveld. « Design and evaluation of a pneumatic actuation unit for a wasp-inspired self-propelled needle ». PLOS ONE 19, no 7 (2 juillet 2024) : e0306411. http://dx.doi.org/10.1371/journal.pone.0306411.
Texte intégralRésumé :
Transperineal laser ablation is a minimally invasive thermo-ablative treatment for prostate cancer that requires the insertion of a needle for accurate optical fiber positioning. Needle insertion in soft tissues may cause tissue motion and deformation, resulting in tissue damage and needle positioning errors. In this study, we present a wasp-inspired self-propelled needle that uses pneumatic actuation to move forward with zero external push force, thus avoiding large tissue motion and deformation. The needle consists of six parallel 0.25-mm diameter Nitinol rods driven by a pneumatic actuation system. The pneumatic actuation system consists of Magnetic Resonance (MR) safe 3D-printed parts and off-the-shelf plastic screws. A self-propelled motion is achieved by advancing the needle segments one by one, followed by retracting them simultaneously. The advancing needle segment has to overcome a cutting and friction force, while the stationary needle segments experience a friction force in the opposite direction. The needle self-propels through the tissue when the friction force of the five stationary needle segments overcomes the sum of the friction and cutting forces of the advancing needle segment. We evaluated the prototype’s performance in 10-wt% gelatin phantoms and ex vivo porcine liver tissue inside a preclinical Magnetic Resonance Imaging (MRI) scanner in terms of the slip ratio of the needle with respect to the phantom or liver tissue. Our results demonstrated that the needle was able to self-propel through the phantom and liver tissue with slip ratios of 0.912–0.955 and 0.88, respectively. The prototype is a promising step toward the development of self-propelled needles for MRI-guided transperineal laser ablation as a method to treat prostate cancer.
46
Szmuc, Tomasz, Rafał Mrówka, Marek Brańka, Jakub Ficoń et Piotr Pięta. « A Novel Method for Fast Generation of 3D Objects from Multiple Depth Sensors ». Journal of Artificial Intelligence and Soft Computing Research 13, no 2 (1 mars 2023) : 95–105. http://dx.doi.org/10.2478/jaiscr-2023-0009.
Texte intégralRésumé :
Abstract Scanning real 3D objects face many technical challenges. Stationary solutions allow for accurate scanning. However, they usually require special and expensive equipment. Competitive mobile solutions (handheld scanners, LiDARs on vehicles, etc.) do not allow for an accurate and fast mapping of the surface of the scanned object. The article proposes an end-to-end automated solution that enables the use of widely available mobile and stationary scanners. The related system generates a full 3D model of the object based on multiple depth sensors. For this purpose, the scanned object is marked with markers. Markers type and positions are automatically detected and mapped to a template mesh. The reference template is automatically selected for the scanned object, which is then transformed according to the data from the scanners with non-rigid transformation. The solution allows for the fast scanning of complex and varied size objects, constituting a set of training data for segmentation and classification systems of 3D scenes. The main advantage of the proposed solution is its efficiency, which enables real-time scanning and the ability to generate a mesh with a regular structure. It is critical for training data for machine learning algorithms. The source code is available at https://github.com/SATOffice/improved_scanner3D.
47
Soponar, Florin, Augustin C. MoŢ et Costel Sârbu. « High-Performance Thin-Layer Chromatography and Three-Dimensional Image Analysis for the Determination of Rutin in Pharmaceutical Preparations ». Journal of AOAC INTERNATIONAL 93, no 3 (1 mai 2010) : 804–10. http://dx.doi.org/10.1093/jaoac/93.3.804.
Texte intégralRésumé :
Abstract A novel HPTLC method was developed for fast and simple quantitative determination of rutin in pharmaceutical preparations. The proposed method combines the advantages of HPTLC with the comfort and the convenience of digital processing of images. For the separation of rutin, silica gel with attached amino groups was used as the stationary phase and ethyl acetateformic acidmethanolwater (10 + 0.9 + 1.1 + 1.7, v/v/v/v) as the mobile phase. The chromatographic plate was sprayed with 2-aminoethyldiphenyl borate solution for visual detection of the spots. For the construction of a three-dimensional chromatogram, Melanie 7.0 software was used together with an HP flatbed scanner that allowed capture of the images on chromatographic plates. The calibration curve was linear within the range of 0.954.78 g/spot with an r value of 0.9984. The RSD for six replicates at three concentration levels was less than 3, while the recovery was between 97.28 and 103.27. The proposed method was found to be simple, precise, sensitive, and accurate and has been applied for the determination of rutin in two commercial drugs. The results were compared with the results of other techniques that generate bidimensional chromatograms and validated by UV-Vis spectrophotometry.
48
Sadeghi, F., et H. Arefi. « OCCLUDED AREA REMOVING FROM HANDHELD LASER SCANNER DATA DURING 3D BUILDING MODELLING ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-4/W18 (19 octobre 2019) : 935–39. http://dx.doi.org/10.5194/isprs-archives-xlii-4-w18-935-2019.
Texte intégralRésumé :
Abstract. 3D building modelling has been turned to be one of the most interesting and hottest subjects in photogrammetry in last two decades, and it seems that photogrammetry provides the only economic means to acquire truly 3D city-data. Most of the researches proposed methods for 3d building modelling in LoD2 using aerial images and LIDAR data and the produced models will be enriched by oblique images, therefore there is always a demand for a user to interpret the façade or in other manual building reconstruction process the operator should draw boundaries to represent the building model and the process will be too time-consuming for 3d modelling for a whole city. Creating building facade models for a whole city requires considerable work, therefore for decades, much research has been dedicated to the automation of this reconstruction process. Nowadays researchers attempt to recommend a new method which is flexible to model hug variety of buildings and has a solution for several challenges such as irrelevant objects (pedestrians, trees, traffic signs, etc.), occluded areas and non-homogenous data. Based on various 3d building models applications, namely navigation systems, location-based system, city planning and etc. the demand for adding semantic features (such as windows and doors) is increasing and becoming more essential, therefore simple blocks as the representation of 3d buildings aren’t sufficient anymore. Therefore 2.5 models which show the façade details using pixel values have been substituted by LoD3 models recently.The lack of automation in image based approaches can be explained by the difficulties in image interpretation. Specifically, factors like illumination and occlusion can cause considerable confusion for machine understanding and some conditions (relative orientation, feature matching, etc.) need to be accurately determined to transfer image pixels to 3D coordinates. In recent years, terrestrial laser scanning data has been proven as a valuable source for building facade reconstruction. The point density of stationary laser scanning in urban areas can be up to hundreds or thousands of points per square meter, which is high enough for documenting most details on building facades. In comparison with image-based modelling, several steps such as image matching, intersection and resection will be eliminated, while there is no need to image interpret in laser data-based reconstruction approaches, these methods face major challenges such as extracting meaningful structures from a huge amount of data.This paper presents a data-driven algorithm for façade reconstruction, using a handheld laser scanner, Zebedee. The mentioned device is consisting of 2d laser scanner and an inertial measurement unit mounted on one or two springs, it has 270-degree field of view. Its mass is 210 g which makes it ideal for low measurement and it is maximum range is 30 m. The proposed method was implemented by using the Zebedee point cloud in order to determine the challenges of zeb1 data and ensure that the introduced device can be practical for 3d reconstruction.Due to obstacle existence, operator gross errors while data capturing and façade elements arrangement, there will always be occluded area and shadows in produced data. Occluded area cause tribulation in machine understanding and problems for automatic reconstruction algorithms. The proposed method represents a new way to detect occluded area and remove the artificial objects which are produced by them. The 3d point cloud is used to cover all façade elements and details, also image matching and producing 3-dimensional data steps will be omitted from the process.The proposed workflow is indicated in figure 1. Most researches such as road, building or other objects detection and reconstruction put ground points detection in priority in order to decrease data volume and processing time, so as a pre-processing step, point cloud is classified into two separate groups (non-ground and ground points).
49
Valova, G. S., A. E. Akulov, O. B. Bogomyakova, A. A. Tulupov et A. A. Cherevko. « Comparison of the mathematical modelling results of the relationship between cerebral ventricular size and capillary pressure based on experimental and clinical data ». Сибирский научный медицинский журнал 44, no 1 (27 février 2024) : 15–22. http://dx.doi.org/10.18699/ssmj20240102.
Texte intégralRésumé :
Aim of the study was to compare the results of mathematical modelling of the dependence between brain ventricle size and capillary pressure for humans and animals based on the equations of multicomponent poroelastic filtration for brain parenchyma. Material and methods. The study included two groups of animals - 4 male mice of each inbred line C57Bl/6 and BALB/C at the age of 12 weeks – and 4 healthy volunteers. The brain and cerebrospinal fluid system images of mice were obtained using an 11.7 T horizontal MR scanner, group of humans were examined using the Ingenia 3.0 T MRI scanner. An axial section at the level of –0.5 mm from bregma in the mouse groups and a frontal slice at the level of the middle of the bodies of the lateral and third ventricles, posterior to the foramen of Monroe in the human group were chosen as the geometry for mathematical modelling. Mathematical modelling is based on the stationary mathematical model of multicomponent poroelastic filtration. Multiple linear regression of mean ventricular wall displacement on fluid media interaction parameters was constructed to compare results obtained. Regression coefficients were compared using nonparametric analysis of variance based on the Kraskell–Wallis criterion and post-hoc Dunn’s criterion with Hill’s correction Results. A qualitative coincidence in the behavior of capillary pressure and mean ventricular wall displacement was demonstrated for the human and mouse groups. No significant differences were found between the two animal lines. For the animals characterized by small ventricular size (BALB/c), greater similarity to humans is observed than for the genetic line with hypertrophied ventricles (C57Bl/6). A significant difference between humans and mice is observed only for capillary-venous interaction. Conclusions. The low variance within groups and insignificant discrepancy between groups indicate the possibility of further accumulation of empirical data to establish correction coefficients of the animal model, which will bring it more in line with the model for humans. Thus, the analyzed models are sufficiently comparable with each other.
50
Patel, Gopi, Arshad Vohra et Samir Shah. « Stability Indicating HPTLC Method for Simultaneous Estimation of Sacubitril and Valsartan in their Pharmaceutical Dosage Form ». International Journal of Pharmaceutical Sciences and Nanotechnology 11, no 4 (31 juillet 2018) : 4208–18. http://dx.doi.org/10.37285/ijpsn.2018.11.4.8.
Texte intégralRésumé :
A simple, precise, accurate and rapid high performance thin layer chromatographic method has been developed and completely validated for the estimation of Valsartan and Sacubitril in pharmaceutical dosage forms. Quantification of Valsartan and Sacubitril were carried out with precoated silica gel aluminum Plate 60 F254, (20 cm ×10 cm) 100 μm thickness as stationary phase. Toluene: Methanol: Ethyl Acetate: Glacial Acetic acid (8:2:1:1 % v/v/v). The optimized chamber saturation time before chromatographic development was 20 min at room temperature (25ºC ± 2). The length of chromatographic run was 8 cm which took average 15 min to develop. Densitometry scanning was performed using Camag TLC scanner IV with Win CATS software (V 1.4.6.2002, Camag). Optimized chromatogram of Valsartan and Sacubitril having Rf of 0.43 and 0.33, respectively. Linear relationship between peak area and concentration of standard was evaluated over the concentration range expressed in ng/band by making five replicate measurements in the concentrations range of 400-1400 ng/band and 4000-14,000 ng/band, respectively for Valsartan and Sacubitril. Literature reveals that there was no any method developed using HPTLC in simultaneous estimation of Valsartan and Sacubitril in their pharmaceutical dosage form. The proposed method can be successfully applied for the estimation of drug content of different marketed formulations.