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Journal articles on the topic 'Volumetric accuracy'

Author: Grafiati

Published: 4 June 2021

Last updated: 15 February 2022

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1

Hoyt, Kenneth, Felix A. Hester, Randall L. Bell, Mark E. Lockhart, and Michelle L. Robbin. "Accuracy of Volumetric Flow Rate Measurements." Journal of Ultrasound in Medicine 28, no. 11 (November 2009): 1511–18. http://dx.doi.org/10.7863/jum.2009.28.11.1511.

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2

Park, Cheol-Woo, Jin-ho Kim, Yu-Kyeong Seo, Sae-Rom Lee, Ju-Hee Kang, Song-Hee Oh, Gyu-Tae Kim, Yong-Suk Choi, and Eui-Hwan Hwang. "Volumetric accuracy of cone-beam computed tomography." Imaging Science in Dentistry 47, no. 3 (2017): 165. http://dx.doi.org/10.5624/isd.2017.47.3.165.

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3

STULL, JILL C., PHILIP J. SCHNEIDER, ALLEN ERENBERG, and RICHARD D. LEFF. "Decreased flow accuracy from volumetric infusion pumps." Critical Care Medicine 17, no. 9 (September 1989): 926–28. http://dx.doi.org/10.1097/00003246-198909000-00018.

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4

Sarina, Shuyou Zhang, and Jinghua Xu. "Transmission system accuracy optimum allocation for multiaxis machine tools’ scheme design." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 227, no. 12 (March 25, 2013): 2762–79. http://dx.doi.org/10.1177/0954406213479723.

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Transmission components are the main mechanical elements in a machine system, the accuracy level of the transmission system is one of the major sources of the machining error of multiaxis machine tools. This article investigates motion error analysis, volumetric motion error model for transmission system and the accuracy allocation method for multiaxis machine tools during the early design stage. For this purpose, a transmission system volumetric motion error model, which is based on the motion error matrix and screw theory, is derived for mapping transmission components’ error parameters to the volumetric motion errors of machine tools. The volumetric motion error matrix combines motion errors along the machine tools’ kinematic chains. Subsequently, the volumetric motion error model is expressed as a volumetric motion error twist, which is formulated from the volumetric motion error matrix. Additionally, the transmission system volumetric motion error twist model is used as design criteria for accuracy optimum allocation, with constraints on the twist magnitude and design variable limits. Then, design optimization is performed by using a multiobjective nonlinear optimization technique to minimize the manufacturing cost and volumetric motion error twist pitch. To solve this multiple objective optimum problem, this study proposes an approach integrating Lagrange multiplier and gradient descent operator with non-dominated sorting genetic algorithm-II (NSGA-II). Modified non-dominated sorting genetic algorithm-II searches for an allocation scheme Pareto optimal front. Consequently, VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR) determines the best compromise solution from the Pareto set. Finally, a numerical experiment for the optimal design of a numerical control machine tool is conducted, which highlights the advantages of the proposed methodology.

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Guo, Qian Jian, Qing Wen Qu, and Jian Guo Yang. "Application of Ant Colony Algorithm to Volumetric Thermal Error Modeling and Compensation of a CNC Machine Tool." Applied Mechanics and Materials 170-173 (May 2012): 3487–90. http://dx.doi.org/10.4028/www.scientific.net/amm.170-173.3487.

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Volumetric errors are the major contributor to the dimensional errors of a workpiece in precision machining. Error compensation technique is a cost-effective way to reduce volumetric errors. Accurate modeling of volumetric errors is a prerequisite of error compensation. In this paper, a volumetric error model was proposed by using neural networks based on ant colony algorithm. Finally, a volumetric error compensation system was developed based on the proposed model, and which has been applied to a CNC machine tool in daily production. The results show that the volumetric errors are reduced and the machining accuracy of the machine tool is improved.

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Liu, Yi Lei, Dong Gao, and Gang Wei Cui. "Volumetric Error Model of Large CNC Machine Tool and Verification Based on Particle Swarm Optimization." Key Engineering Materials 579-580 (September 2013): 76–79. http://dx.doi.org/10.4028/www.scientific.net/kem.579-580.76.

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Volumetric error has large effect on machine tool accuracy; improving CNC machine tool accuracy through error compensation has received significant attention recently. This paper intends to represent volumetric error measurement based on laser tracker. The volumetric error is modeled by homogenous transformation matrix with each coordinate corresponding to each motion axis. Based on parts of spatial points volumetric error, the geometric errors which affect volumetric positioning error are verified through particle swarm optimization with the L2 parameters as the target function. The chebyshev orthogonal polynomials are applied to approximate geometric errors.

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7

Holub, Michal, Robert Jankovych, Jan Vetiska, Jan Sramek, Petr Blecha, Jan Smolik, and Petr Heinrich. "Experimental Study of the Volumetric Error Effect on the Resulting Working Accuracy—Roundness." Applied Sciences 10, no. 18 (September 8, 2020): 6233. http://dx.doi.org/10.3390/app10186233.

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Currently, various types of software compensations are applied to machine tools. Their aim is to increase the working accuracy of the tools. The improvement in working accuracy is then further assessed according to the increase in the dimensional and shape accuracy or the surface quality of the workpiece. This publication describes the effects of the volumetric accuracy of a machine tool on the working accuracy of a workpiece, where total roundness (RONt) is evaluated in multiple cuts. In the experiment, two test workpieces are manufactured on a three-axis milling machining centre. The first is made using a standard machine setup while the second with activated volumetric compensation. The LaserTRACER self-tracking laser interferometer is used to compensate for volumetric accuracy. In the second part, verification measurements are performed with a Ballbar, where roundness error is evaluated according to ISO 230-4. Then two test workpieces are machined, and, in the last part, measurement is performed on Talyrond 595S roundness measuring equipment. Finally, the results are analysed and the dependence between the volumetric accuracy, the circularity error of the machine and the working accuracy of the CNC machine tool is established, represented by the RONt of the workpiece. This paper presents new and unpublished relations between the volumetric accuracy of the machine tool and the RONt of the workpiece.

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Wang, K., X. Sheng, and R. Kang. "Volumetric Error Modelling, Measurement, and Compensation for an Integrated Measurement-Processing Machine Tool." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 224, no. 11 (April 27, 2010): 2477–86. http://dx.doi.org/10.1243/09544062jmes2200.

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The volumetric error of a measurement-processing integrated machine tool was studied by using a complicated surface workpiece grinding machine as a special example. The model of volumetric error was established by using homogeneous transformation matrices, and the effect of volumetric error on coordinate transformation between the measurement and the processing work station was analysed. Various error components of the machine tool were measured with a laser interferometer and an electronic level, and the volumetric error was compensated by external software. With a ball bar system and grinding experiments, the volumetric position accuracy was tested after compensation. The experiment results illustrated that both the volumetric position accuracy and machining precision were improved dramatically after compensation.

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9

Chromy, Adam. "Application of High-Resolution 3D Scanning in Medical Volumetry." International Journal of Electronics and Telecommunications 62, no. 1 (March 1, 2016): 23–31. http://dx.doi.org/10.1515/eletel-2016-0003.

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Abstract This paper deals with application of 3D scanning technology in medicine. Important properties of 3D scanners are discussed with emphasize on medical applications. Construction of medical 3D scanner according to these specifications is described and practical application of its use in medical volumetry is presented. Besides volumetry, such 3D scanner is usable for many other purposes, like monitoring of recovery process, ergonomic splint manufacturing or inflammation detection. 3D scanning introduces novel volumetric method, which is compared with standard methods. The new method is more accurate compared to present ones. Principles of this method are discussed in paper and its accuracy is evaluated and experimentally verified.

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10

Yoon, Jung Soo, Hwang Jung Kim, Jin Yun Kim, and Sun Gyoo Park. "Accuracy and Continuity of Infusion Devices with Volumetric Analyzer." Korean Journal of Anesthesiology 28, no. 5 (1995): 611. http://dx.doi.org/10.4097/kjae.1995.28.5.611.

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11

Chisholm, R. A., S. Stenning, and T. D. Hawkins. "The accuracy of volumetric measurement of high-grade gliomas." Clinical Radiology 40, no. 1 (January 1989): 17–21. http://dx.doi.org/10.1016/s0009-9260(89)80007-8.

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12

Ximénez-Fyvie, Laurie Ann, Cecilia Ximénez-García, Pablo Manuel Carter-Bartlett, and Francisco Javier Collado-Webber. "Accuracy of endodontic microleakage results: Autoradiographic vs. volumetric measurements." Journal of Endodontics 22, no. 6 (June 1996): 294–97. http://dx.doi.org/10.1016/s0099-2399(96)80262-7.

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13

Lukina, Svetlana, and Igor Manaenkov. "Methodology of multiaxial machines formats volumetric accuracy comparative evaluation." MATEC Web of Conferences 129 (2017): 01046. http://dx.doi.org/10.1051/matecconf/201712901046.

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14

Naterer, G. F. "SUBGRID VOLUMETRIC QUADRATURE ACCURACY FOR TRANSIENT COMPRESSIBLE FLOW PREDICTIONS." International Journal for Numerical Methods in Fluids 25, no. 2 (July 30, 1997): 143–49. http://dx.doi.org/10.1002/(sici)1097-0363(19970730)25:2<143::aid-fld536>3.0.co;2-w.

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15

Guo, Yan Hua, Xiao Yan Zhang, and Xue Zhong. "Study on Algorithm of Improved Modified Cambridge Model Calculation Accuracy." Advanced Materials Research 1065-1069 (December 2014): 204–7. http://dx.doi.org/10.4028/www.scientific.net/amr.1065-1069.204.

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Roscoe and Burland set the yield surface of the Cambridge model to elliptic and concluded modified Cambridge model. In this paper, the model has been improved and got the accuracy of the elastic-plastic matrix improvement model, by using the Cambridge model to calculate the volumetric strain and shear strain of soil theoreically and inculcating CU triaxial tests to measure the corresponding soil volumetric strain and shear strain and applying least squares theory to simulate the ratio of theoretical calculations and experimental results.

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16

Zhao, Wu, Hao Ran Liu, Guo Ji Wang, and Ling Bing Liu. "Research on Geometric Errors Model and Identification of 5-Axis Machining Center for Processing Turbo Molecular Pump Rotor." Advanced Materials Research 211-212 (February 2011): 784–87. http://dx.doi.org/10.4028/www.scientific.net/amr.211-212.784.

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This paper investigates the accuracy evaluative factors of 5-axis turbo molecular pump rotor machining center.Using rigid body kinematics techniques and homogenous transformation matrices, the systemic geometric volumetric error model are established for error synthesis. Novel volumetric accuracy model can be verified effectiveness better estimation of machine performance, by means of physical simulation and measurement. The effect of the individual axis geometric errors can become increasingly significant as the chain of dependent axis is extended. The effect of the rotary axis and their errors cannot be ignored. Calculating volumetric accuracy as the maximum difference between the error vector at any two positions can be computationally intensive.

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17

Foley, J. L., and E. Harris. "Field calibration of ThetaProbe (ML2x) and ECHO probe (EC-20) soil water sensors in a Black Vertosol." Soil Research 45, no. 3 (2007): 233. http://dx.doi.org/10.1071/sr06156.

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Past studies have shown that soil-specific calibrations are required to attain a higher level of accuracy when measuring soil water content with ThetaProbe and ECHO probe soil water sensors, particularly in swelling clay soils. Both probes were assessed for their capacity to accurately monitor soil water in a deep drainage study on a Black Vertosol. Probes were trialled in situ and calibrated against hand-sampled volumetric measurements. The generic calibrations given by the manufacturers resulted in significant errors in water content estimates for both probes. Using the generic calibration, ECHO probes under-estimated water content by 0.10–0.2 m3/m3, whereas ThetaProbes under-estimated by 0.04 m3/m3 at the wet end and over-estimated by 0.08 m3/m3 at the dry end. The soil-specific calibrations significantly improved the accuracy of both probes. ThetaProbes were chosen for the drainage study. The calibration allowed for accuracy across the full wet–dry range to within 0.001–0.004 m3/m3 of volumetric measurements. ECHO probes were less accurate at the wet end, but still determined soil water content to within 0.02–0.05 m3/m3 of volumetric measurements.

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18

Orman, J., Ö. Gürvit, and D. Bartz. "Accurate Volumetric Measurements of Anatomical Cavities." Methods of Information in Medicine 43, no. 04 (2004): 331–35. http://dx.doi.org/10.1055/s-0038-1633876.

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Summary Objectives: The volumetric assessment of anatomical cavities is of high relevance for various applications in medicine. Based on 3D scanning (i.e., CT) of these cavities, the volume can be determined by counting the volume elements of a segmentation of that cavity. Unfortunately, elements on the boundary of the segmentation require special treatment to obtain accurate volumetric measurements. In this paper, we propose a novel technique that in particular increases the accuracy of the volume estimation for the boundary elements of segmented anatomical objects. Methods: Based on a 3D segmentation of an anatomical cavity, we recursively subdivide boundary volume elements into a set of simple situations, where the volume can be estimated easily. Results: We performed volumetric measurements on seven datasets of phantom models made of plexiglass (see Fig. 1) scanned by a biplane angiography unit and assessed the quality of our method by comparing the measured volume by our novel method and by the fluid required to fill the phantom cavities. Conclusions: Our method calculates a significantly more accurate volume of the segmented cavities than previous methods. Nevertheless, it is only slightly more computationally expensive.

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19

B. K. Fritz, W. C. Hoffmann, J. A. S. Bonds, and M. Farooq. "Volumetric Collection Efficiency and Droplet Sizing Accuracy of Rotary Impactors." Transactions of the ASABE 54, no. 1 (2011): 57–63. http://dx.doi.org/10.13031/2013.36253.

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20

Bobrowski, A. V., O. I. Drachev, and B. M. Gorshkov. "Improving the operational accuracy of shafts by volumetric plastic deformation." Materials Today: Proceedings 30 (2020): 656–59. http://dx.doi.org/10.1016/j.matpr.2020.01.458.

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21

Ahlowalia, M. S., S. Patel, H. M. S. Anwar, G. Cama, R. S. Austin, R. Wilson, and F. Mannocci. "Accuracy of CBCT for volumetric measurement of simulated periapical lesions." International Endodontic Journal 46, no. 6 (December 7, 2012): 538–46. http://dx.doi.org/10.1111/iej.12023.

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22

Li, Winnie, Douglas J. Moseley, Tony Manfredi, and David A. Jaffray. "Accuracy of automatic couch corrections with on-line volumetric imaging*." Journal of Applied Clinical Medical Physics 10, no. 4 (September 2009): 106–16. http://dx.doi.org/10.1120/jacmp.v10i4.3056.

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23

Jackson, Edward F., Ponnada A. Narayana, Jerry S. Wolinsky, and Timothy J. Doyle. "Accuracy and Reproducibility in Volumetric Analysis of Multiple Sclerosis Lesions." Journal of Computer Assisted Tomography 17, no. 2 (March 1993): 200–205. http://dx.doi.org/10.1097/00004728-199303000-00007.

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24

Vahebi, Mehrdad, and Behrooz Arezoo. "Accuracy improvement of volumetric error modeling in CNC machine tools." International Journal of Advanced Manufacturing Technology 95, no. 5-8 (November 21, 2017): 2243–57. http://dx.doi.org/10.1007/s00170-017-1294-x.

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25

Conder, K., and E. Kaldis. "High accuracy volumetric determination of hydrogen in rare earth hydrides." Journal of the Less Common Metals 146 (January 1989): 205–11. http://dx.doi.org/10.1016/0022-5088(89)90377-9.

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26

Kannath, Santhosh Kumar, Adhithyan Rajendran, Bejoy Thomas, and Jayadevan Enakshy Rajan. "Volumetric T2-weighted MRI improves the diagnostic accuracy of spinal vascular malformations: comparative analysis with a conventional MR study." Journal of NeuroInterventional Surgery 11, no. 10 (March 6, 2019): 1019–23. http://dx.doi.org/10.1136/neurintsurg-2018-014522.

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BackgroundTo date, very little study of the importance of a volumetric T2-weighted MR sequence in the evaluation of spinal vascular malformations (SVMs) has been carried out.ObjectiveTo determine the utility and accuracy of a volumetric T2 MR sequence compared with conventional T2 in the diagnosis of SVMs.MethodsRetrospective analysis of all patients who underwent spinal DSA for suspected SVMs was conducted. Conventional T2 and volumetric T2 MR images were analysed for the presence of flow voids and parenchymal changes, and SVMs were characterized. The sensitivity, specificity, and overall diagnostic accuracy of these MRI diagnoses were calculated.ResultsOf 89 subjects included in the final analysis, 70 patients had angiographically proved SVMs (38 patients with spinal cord arteriovenous malformations [SCAVM—intramedullary or perimedullary] and 32 cases of spinal dural arteriovenous fistula (SDAVF)) and the remaining 19 subjects were normal. The sensitivity and specificity for identification of SVMs were 98.1% and 90% for volumetric T2 sequences, compared with 82.8% and 89.4% for conventional T2 MRI, respectively. For characterization of spinal vascular lesions, volumetric MRI showed high sensitivity, specificity, and accuracy for SDAVF (100%, 90%, 97%, respectively) compared with conventional T2 MRI (71.8%, 89%, 79%, respectively). The positive likelihood ratio was high and negative likelihood ratio was zero for volumetric MRI evaluation of SDAVF, while these ratios were comparable between the two sequences for SCAVM.ConclusionVolumetric T2 MRI is highly sensitive for the detection of SVMs, especially for SDAVF. Volumetric T2 MRI could be introduced into routine clinical practice in the screening of suspected SVMs.

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Guzmán Pérez-Carrillo, Gloria J., Christopher Owen, Katherine E. Schwetye, Spencer McFarlane, Ananth K. Vellimana, Soe Mar, Michelle M. Miller-Thomas, Joshua S. Shimony, Matthew D. Smyth, and Tammie L. S. Benzinger. "The use of hippocampal volumetric measurements to improve diagnostic accuracy in pediatric patients with mesial temporal sclerosis." Journal of Neurosurgery: Pediatrics 19, no. 6 (June 2017): 720–28. http://dx.doi.org/10.3171/2016.12.peds16335.

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OBJECTIVEMany patients with medically intractable epilepsy have mesial temporal sclerosis (MTS), which significantly affects their quality of life. The surgical excision of MTS lesions can result in marked improvement or even complete resolution of the epileptic episodes. Reliable radiological diagnosis of MTS is a clinical challenge. The purpose of this study was to evaluate the utility of volumetric mapping of the hippocampi for the identification of MTS in a case-controlled series of pediatric patients who underwent resection for medically refractory epilepsy, using pathology as a gold standard.METHODSA cohort of 57 pediatric patients who underwent resection for medically intractable epilepsy between 2005 and 2015 was evaluated. On pathological investigation, this group included 24 patients with MTS and 33 patients with non-MTS findings. Retrospective quantitative volumetric measurements of the hippocampi were acquired for 37 of these 57 patients. Two neuroradiologists with more than 10 years of experience who were blinded to the patients' MTS status performed the retrospective review of MR images. To produce the volumetric data, MR scans were parcellated and segmented using the FreeSurfer software suite. Hippocampal regions of interest were compared against an age-weighted local regression curve generated with data from the pediatric normal cohort. Standard deviations and percentiles of specific subjects were calculated. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were determined for the original clinical read and the expert readers. Receiver operating characteristic curves were generated for the methods of classification to compare results from the readers with the authors' results, and an optimal threshold was determined. From that threshold the sensitivity, specificity, PPV, and NPV were calculated for the volumetric analysis.RESULTSWith the use of quantitative volumetry, a sensitivity of 72%, a specificity of 95%, a PPV of 93%, an NPV of 78%, and an area under the curve of 0.84 were obtained using a percentage difference of normalized hippocampal volume. The resulting specificity (95%) and PPV (93%) are superior to the original clinical read and to Reader A and Reader B's findings (range for specificity 74%–86% and for PPV 64%–71%). The sensitivity (72%) and NPV (78%) are comparable to Reader A's findings (73% and 81%, respectively) and are better than those of the original clinical read and of Reader B (sensitivity 45% and 63% and NPV 71% and 70%, respectively).CONCLUSIONSVolumetric measurement of the hippocampi outperforms expert readers in specificity and PPV, and it demonstrates comparable to superior sensitivity and NPV. Volumetric measurements can complement anatomical imaging for the identification of MTS, much like a computer-aided detection tool would. The implementation of this approach in the daily clinical workflow could significantly improve diagnostic accuracy.

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Zhang, Hong Xin, and Qian Jian Guo. "Research on Volumetric Error Measurement, Modeling and Compensation for NC Machine Tools." Applied Mechanics and Materials 513-517 (February 2014): 4202–5. http://dx.doi.org/10.4028/www.scientific.net/amm.513-517.4202.

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With the increasing requirements of the machining accuracy of CNC machine tools, the impact of thermal deformation is growing. Thermal error compensation technology can predict and compensate the thermal errors in real-time, and improve the machining accuracy of the machine tool. In this paper, the research objects of thermal error compensation is expanded to the volumetric error of the machine tool, the volumetric error modeling of a three-axis machine tool is fulfilled and a compensator is developed for the compensation experiment, which provides scientific basis for the improvement of the machining accuracy.

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29

Berden, J. H. M., J. M. P. Wokke, and R. A. P. Koene. "Comparative Analysis of Two Volumetrical Ultrafiltration Monitors for Hemodialysis." International Journal of Artificial Organs 9, no. 3 (May 1986): 163–66. http://dx.doi.org/10.1177/039139888600900308.

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Controlled ultrafiltration (UF) during hemodialysis may prevent dialysis associated hypotension. A prerequisite for controlled ultrafiltration is an accurate measurement of ultrafiltration. Volumetric measurement is the best currently available method for this purpose. In this study we compared in a clinical setting two volumetric ultrafiltration monitors (UFM): one device constructed in our hospital using oval flowmeters (UFM-N) and the other using electromagnetic flow transducers (UFM-G: UFM 10-2, Gambro Lund Sweden). The UF measurements of both UFM's were compared with UF calculated from bedscales weight monitoring and standard scales determinations. During dual needle hemodialysis (n = 8) with a hollow fiber dialyzer the accuracy of the UFM-N was 91% and that of the UFM-G 97%. During dual needle dialysis with a parallel flow dialyzer the UFM-N appeared to be more sensitive for pulsatile changes in the dialysate flow due to the greater compliance of this type of dialyzer. The accuracy of the UFM-N in this setting was 80%, while that of the UFM-G was 87% (n = 11). During single needle dialysis with a parallel flow dialyzer (n = 14) only the UFM-G was tested and it measured UF with an accuracy of 92%. Finally the UFM-G can control UF actively by adjusting the TMP to obtain a given UF rate. The accuracy of the UFM-G in this setting was 94%, and the lineair regression correlation coefficient between planned UF and actually obtained UF was 0.974 (n - 61). In conclusion volumetric monitoring of UF is accurate and reliable, but its accuracy is dependent on the type of dialyzer used. The UFM-G proved to be useful in every dialysis modality tested, while the UFM-N can be used in dual-needle dialysis using hollow fiber dialyzers.

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Al-Daccak, M., and J. Angeles. "The Calculation of the Volumetric Properties of Sweep-Generated Solids Via Line Integration." Journal of Mechanical Design 115, no. 1 (March 1, 1993): 110–18. http://dx.doi.org/10.1115/1.2919306.

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A key issue in the geometric and mechanical analyses of machine elements with complex shapes such as turbine blades and bevel gears is the accurate and economic computation of their volumetric properties, namely, volume, centroid coordinates, and inertia tensor. A method is proposed here for the computation of these properties that is applicable to sweep-generated solids based only on their 2D generating contour and their sweeping parameters. Thus, the direct 3D calculations of the volumetric properties of such solids are reduced to simple 2D calculations. Comparisons of numerical results are presented, which show that the volumetric properties of this class of solids can be effectively performed in a computationally reduced fashion which, additionally, enhances the accuracy of the computed values.

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Sezer, Sümeyye, Martin J. van Amerongen, Hans H. K. Delye, and Mark ter Laan. "Accuracy of the neurosurgeons estimation of extent of resection in glioblastoma." Acta Neurochirurgica 162, no. 2 (October 28, 2019): 373–78. http://dx.doi.org/10.1007/s00701-019-04089-8.

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Abstract Background The surgeons’ estimate of the extent of resection (EOR) shows little accuracy in previous literature. Considering the developments in surgical techniques of glioblastoma (GBM) treatment, we hypothesize an improvement in this estimation. This study aims to compare the EOR estimated by the neurosurgeon with the EOR determined using volumetric analysis on the post-operative MR scan. Methods Pre- and post-operative tumor volumes were calculated through semi-automatic volumetric assessment by three observers. Interobserver agreement was measured using intraclass correlation coefficient (ICC). A univariate general linear model was used to study the factors influencing the accuracy of estimation of resection percentage. Results ICC was high for all three measurements: pre-operative tumor volume was 0.980 (0.969–0.987), post-operative tumor volume 0.974 (0.961–0.984), and EOR 0.947 (0.917–0.967). Estimation of EOR by the surgeon showed moderate accuracy and agreement. Multivariable analysis showed a statistically significant effect of operating neurosurgeon (p = 0.01), use of fluorescence (p < 0.001), and resection percentage (p < 0.001) on the accuracy of the EOR estimation. Conclusion All measurements through semi-automatic volumetric analysis show a high interobserver agreement, suggesting this to be a reliable assessment of EOR. We found a moderate reliability of the surgeons’ estimate of EOR. Therefore, (early) post-operative MRI scanning for evaluation of EOR remains paramount.

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Xu, Yun, and Xue Meng Xu. "Influence of Edible Oil Weight Filling Accuracy." Applied Mechanics and Materials 200 (October 2012): 507–10. http://dx.doi.org/10.4028/www.scientific.net/amm.200.507.

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The article discusses the characteristics of volumetric filling and weighing filling for edible oil. Influence of filling accuracy for edible oil has been studied in accordance with weight filling. It pointes out that error of weight filling system results from load cell error, error caused by filling valve operating time delay, error by PLC response time delay and shock error by liquid flow. After analyzing the causes of each error, it puts forward how to improve weight filling accuracy.

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Snell, John W., Jason Sheehan, Matei Stroila, and Ladislau Steiner. "Assessment of imaging studies used with radiosurgery: a volumetric algorithm and an estimation of its error." Journal of Neurosurgery 104, no. 1 (January 2006): 157–62. http://dx.doi.org/10.3171/jns.2006.104.1.157.

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✓ The Gamma Knife has played an increasingly important role in the neurosurgical treatment of patients. Intracranial lesions are not removed by radiosurgery. Rather, the goal of treatment is to induce tumor control. During planning, the creation of dose–volume histograms requires an accurate volumetric analysis of intracranial lesions selected for radiosurgery. In addition, an accurate follow-up imaging analysis of tumor volume is essential for assessing the results of radiosurgery. Nevertheless, sources of volumetric error and their expected magnitudes must be properly understood so that the operator may correctly interpret apparent changes in tumor volume. In this paper, the authors examine the often-neglected contributions of imaging geometry (principally image slice thickness and separation) to overall volumetric error. One of the fundamental sources of volumetric error is that resulting from the geometry of the acquisition protocol. The authors consider the image sampling geometry of tomographic modalities and its contribution to volumetric error through a simulation framework in which a synthetic digital tumor is taken as the primary model. Because the exact volume of the digital phantom can be computed, the volume estimates derived from tomographic “slicing” can be directly compared precisely and independently from other error sources. In addition to providing empirical bounds on volumetric error, this approach provides a tool for guiding the specification of imaging protocols when a specific volumetric accuracy, or volume change sensitivity, for particular structures is sought a priori. Using computational geometry techniques, the volumetric error associated with image acquisition geometry was shown to be dependent on the number of slices through the region of interest (ROI) and the lesion volume. With a minimum of five slices through the ROI, the volume of a compact lesion could be calculated accurately with less than 10% error, which was the predetermined goal for the purposes of computing accurate dose–volume histograms and determining follow-up changes in tumor volume. Accurate dose–volume histograms can be generated and follow-up volumetric assessments performed, assuming accurate lesion delineation, when the object is visualized on at least five axial slices. Volumetric analysis based on fewer than five slices yields unacceptably larger errors (that is, > 10%). These volumetric findings are particularly relevant for radiosurgical treatment planning and follow-up analysis. Through the application of this volumetric methodology and a greater understanding of the error associated with it, neurosurgeons can better perform radiosurgery and assess its outcome.

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Chesnokov, V. I. "Improving the estimation of methodological errors in reproducing the volumetric air flow rate by reference critical nozzle." Metrologiya, no. 1 (May 31, 2021): 4–30. http://dx.doi.org/10.32446/0132-4713.2021-1-4-30.

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In the development of the previously obtained results a more accurate estimate of the methodological error in reproducing the volumetric air flow rate by reference critical nozzle is given, associated with the choice of the gas flow model and due to taking into account the initial kinetic energy of the flow at the nozzle inlet. Based on improved flow model an analytical evaluation of the methodological error in reproducing the volumetric air flow rate by reference critical nozzle, which is due to a change in the humidity of the working air, has been carried out. It is shown that the methodological error in reproducing the volumetric air flow rate by reference critical nozzle, associated with a change in the air humidity, as well as the analogies methodical error caused by the existence of the initial kinetic energy of the flow, must be taken part in accuracy characteristics at the real operating conditions of the standard volumetric air flow rate using critical nozzles.

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Pupulim, L. F., M. Ronot, V. Paradis, S. Chemouny, and V. Vilgrain. "Volumetric measurement of hepatic tumors: Accuracy of manual contouring using CT with volumetric pathology as the reference method." Diagnostic and Interventional Imaging 99, no. 2 (February 2018): 83–89. http://dx.doi.org/10.1016/j.diii.2017.11.002.

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Basilio, Carlos, Christian Villeda, Carolina Culebro, Francisco Rodríguez-Covarrubias, and Ricardo Castillejos-Molina. "Volumetric assessment of lymph node metastases in patients with non-seminomatous germ cell tumors treated with chemotherapy." Canadian Urological Association Journal 9, no. 5-6 (May 13, 2015): 247. http://dx.doi.org/10.5489/cuaj.2152.

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Introduction: We evaluate volumetry and RECIST (Response Evaluation Criteria In Solid Tumors) as methodologies for response after chemotherapy for non-seminomatous germ cell tumour with retroperitoneal lymph node metastases.Methods: We performed a retrospective analysis of non-seminomatous testicular tumours and concurrent retroperitoneal lymph node metastases, which received chemotherapy and had computed tomography scans before and after treatment. Volumetric analysis and RECIST criteria were used to calculate response rates. We included a new category (favourable response) for patients with response rates between 70%. We calculated the correlation between volumetric and RECIST criteria with histological and clinical variables.Results: In total, 18 patients met the inclusion criteria. Histopathologic analysis of orchiectomy showed teratoma in 55.5% of patients, and those without teratoma had predominantly embryonal carcinoma. The mean baseline volume of retroperitoneal metastases was 447 cc, the mean post-chemotherapy volume was 33.6 cc, and the response rate was 62.6%. According to RECIST criteria, the mean baseline diameter was 4.93 cm, the mean post-chemotherapy diameter was 2.39 cm, and the response rate was 42.4%. Large post-chemotherapy residual masses correlated in both classifications with teratoma. The response rate was associated with the need for surgical treatment and the volumetric classification correlated with the need for lymphadenectomy.Conclusions: This study evaluated volumetry as a way to measure clinical response in lymph node metastases of non-seminomatous germ cell tumours. Volumetric analysis is the next step in the evaluation of response rate; its accuracy remains to be determined. Teratoma had greater residual masses and our classification correlated with the need for lymphadenectomy.

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Vasiliu, Mihaela Păpușa, Liliana Sachelarie, Carmen Stadoleanu, Cătălina Gîrbea, and Agripina Zaharia. "Volumetric Change as a Parameter for the Accuracy of Impression Materials." Journal of Biomimetics, Biomaterials and Biomedical Engineering 36 (March 2018): 17–23. http://dx.doi.org/10.4028/www.scientific.net/jbbbe.36.17.

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In this paper we studied the behavior of some impression materials such as alginate, condensation and addition silicones, considering the following parameters: the reproductive capacity of morphological details - dimensional stability - the ability to reproduce with accuracy the ratio between morphological elements. The essential conditions that an impression material should fulfill are plasticity, fidelity, flexibility, good mechanical strength, dimensional stability, suitable setting time and compatibility with materials from which the models are manufactured.The study results indicated that condensation silicones present the highest volumetric changes, their contraction being the result of the evaporation of volatile byproducts.The dimensional stability of fingerprint materials is one of the variables that contribute to the accuracy or inaccuracy of dental prostheses, other factors being represented by the changes occurring during the preparation of the fingerprint material as well as the fingerprinting techniques.

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Vladimir, Sokolov, and Basalaev Konstantin. "Laser Measurements Based for Volumetric Accuracy Improvement of Multi-axis Systems." Physics Procedia 56 (2014): 1297–304. http://dx.doi.org/10.1016/j.phpro.2014.08.054.

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Emir, Faruk, Simel Ayyildiz, Bulent Piskin, and Cumhur Sipahi. "Volumetric evaluation and three-dimensional accuracy of different elastomeric impression materials." Measurement 127 (October 2018): 436–42. http://dx.doi.org/10.1016/j.measurement.2018.06.002.

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Diamond, Bram R., Christine L. Mac Donald, Aina Frau-Pascual, Samuel B. Snider, Bruce Fischl, Kristen Dams-O'Connor, and Brian L. Edlow. "Optimizing the accuracy of cortical volumetric analysis in traumatic brain injury." MethodsX 7 (2020): 100994. http://dx.doi.org/10.1016/j.mex.2020.100994.

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Park, Jong Min, Jung‐in Kim, and So‐Yeon Park. "Modulation indices and plan delivery accuracy of volumetric modulated arc therapy." Journal of Applied Clinical Medical Physics 20, no. 6 (April 30, 2019): 12–22. http://dx.doi.org/10.1002/acm2.12589.

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Chromy, Adam. "High-Accuracy Volumetric Measurements of Soft Tissues using Robotic 3D Scanner." IFAC-PapersOnLine 48, no. 4 (2015): 318–23. http://dx.doi.org/10.1016/j.ifacol.2015.07.054.

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Scaggion, A., A. Negri, M. Paiusco, A. Roggio, M. A. Rossato, and F. Simonato. "Evaluating the accuracy of volumetric modulated arc therapy (VMAT) treatments delivery." Physica Medica 30 (2014): e69. http://dx.doi.org/10.1016/j.ejmp.2014.07.210.

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Sircar, Sarmishtha, Cheng-Yu Wang, and Angela D. Lueking. "Design of high pressure differential volumetric adsorption measurements with increased accuracy." Adsorption 19, no. 6 (July 11, 2013): 1211–34. http://dx.doi.org/10.1007/s10450-013-9558-8.

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Sothmann, Thilo, Tobias Gauer, and René Werner. "4D dose simulation in volumetric arc therapy: Accuracy and affecting parameters." PLOS ONE 12, no. 2 (February 23, 2017): e0172810. http://dx.doi.org/10.1371/journal.pone.0172810.

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Senior, Louise M., and Dunbar P. Birnie III. "Accurately Estimating Vessel Volume from Profile Illustrations." American Antiquity 60, no. 2 (April 1995): 319–34. http://dx.doi.org/10.2307/282143.

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The highly fragmented nature of most archaeological ceramic assemblages makes whole or reconstructible vessels valuable and rare finds. Vessel volume has rarely been systematically quantified because convenient reconstruction methods dealing with sherds and partial vessels have been lacking. Now, with the method presented in this paper, highly accurate volumetric capacities of fragmented vessels can be calculated from carefully prepared vessel profile illustrations. The profile is digitized using a small number of points per vessel (20 to 30 points are usually sufficient). These data are then converted to a volumetric measure using a computerized algorithm based on the geometry of stacked bevel-walled cylinders. This method of determining vessel volumes was tested and shown to be highly repeatable and accurate. Quantifiable sources of error are generally limited to less than one percent per vessel, with the final accuracy limited chiefly by the quality of illustration. With this computerized technique, fragmented vessels no longer need to be fully reconstructed in order to obtain volumetric information.

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Petrillo, Mario, Roberta Fusco, Orlando Catalano, Mario Sansone, Antonio Avallone, Paolo Delrio, Biagio Pecori, Fabiana Tatangelo, and Antonella Petrillo. "MRI for Assessing Response to Neoadjuvant Therapy in Locally Advanced Rectal Cancer Using DCE-MR and DW-MR Data Sets: A Preliminary Report." BioMed Research International 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/514740.

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To evaluate MRI for neoadjuvant therapy response assessment in locally advanced rectal cancer (LARC) using dynamic contrast enhanced-MRI (DCE-MRI) and diffusion weighted imaging (DWI), we have compared magnetic resonance volumetry based on DCE-MRI (V(DCE)) and on DWI (V(DWI)) scans with conventional T2-weighted volumetry (V(C)) in LARC patients after neoadjuvant therapy. Twenty-nine patients with LARC underwent MR examination before and after neoadjuvant therapy. A manual segmentation was performed on DCE-MR postcontrast images, on DWI (b-value 800 s/mm2), and on conventional T2-weighted images by two radiologists. DCE-MRI, DWI, and T2-weigthed volumetric changes before and after treatment were evaluated. Nonparametric sample tests, interobserver agreement, and receiver operating characteristic curve (ROC) were performed. Diagnostic performance linked to DCE-MRI volumetric change was superior to T2-w and DW-MRI volumetric changes performance (specificity 86%, sensitivity 93%, and accuracy 93%). Area Under ROC (AUC) ofV(DCE) was greater than AUCs ofV(C) andV(DWI) resulting in an increase of 15.6% and 11.1%, respectively. Interobserver agreement between two radiologists was 0.977, 0.864, and 0.756 forV(C),V(DCE), andV(DWI), respectively.V(DCE) seems to be a promising tool for therapy response assessment in LARC. Further studies on large series of patients are needed to refine technique and evaluate its potential value.

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Laves, Max-Heinrich, Lüder A. Kahrs, and Tobias Ortmaier. "Volumetric 3D stitching of optical coherence tomography volumes." Current Directions in Biomedical Engineering 4, no. 1 (September 1, 2018): 327–30. http://dx.doi.org/10.1515/cdbme-2018-0079.

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AbstractOptical coherence tomography (OCT) is a noninvasive medical imaging modality, which provides highresolution transectional images of biological tissue. However, its potential is limited due to a relatively small field of view. To overcome this drawback, we describe a scheme for fully automated stitching of multiple 3D OCT volumes for panoramic imaging. The voxel displacements between two adjacent images are calculated by extending the Lucas-Kanade optical flow a lgorithm to dense volumetric images. A RANSAC robust estimator is used to obtain rigid transformations out of the resulting flow v ectors. T he i mages a re t ransformed into the same coordinate frame and overlapping areas are blended. The accuracy of the proposed stitching scheme is evaluated on two datasets of 7 and 4 OCT volumes, respectively. By placing the specimens on a high-accuracy motorized translational stage, ground truth transformations are available. This results in a mean translational error between two adjacent volumes of 16.6 ± 0.8 μm (2.8 ± 0.13 voxels). To the author’s knowledge, this is the first reported stitching of multiple 3D OCT volumes by using dense voxel information in the registration process. The achieved results are sufficient for providing high accuracy OCT panoramic images. Combined with a recently available high-speed 4D OCT, our method enables interactive stitching of hand-guided acquisitions.

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Fabius, Timon M., Michiel M. M. Eijsvogel, Marjolein G. J. Brusse-Keizer, Olivier M. Sanchez, Franck Verschuren, and Frans H. C. de Jongh. "Retrospective validation of a new volumetric capnography parameter for the exclusion of pulmonary embolism at the emergency department." ERJ Open Research 4, no. 4 (October 2018): 00099–2018. http://dx.doi.org/10.1183/23120541.00099-2018.

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Volumetric capnography might be used to exclude pulmonary embolism (PE) without the need for computed tomography pulmonary angiography. In a pilot study, a new parameter (CapNoPE) combining the amount of carbon dioxide exhaled per breath (carbon dioxide production (VCO2)), the slope of phase 3 of the volumetric capnogram (slope 3) and respiratory rate (RR) showed promising diagnostic accuracy (where CapNoPE=(VCO2×slope 3)/RR).To retrospectively validate CapNoPE for the exclusion of PE, the volumetric capnograms of 205 subjects (68 with PE) were analysed, based on a large multicentre dataset of volumetric capnograms from subjects with suspected PE at the emergency department. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve and diagnostic accuracy of the in-pilot established threshold (1.90 Pa·min) were calculated. CapNoPE was 1.56±0.97 Pa·min in subjects with PE versus 2.51±1.67 Pa·min in those without PE (p<0.001). The AUC of the ROC curve was 0.714 (95% CI 0.64–0.79). For the cut-off of ≥1.90 Pa·min, sensitivity was 64.7%, specificity was 59.9%, the negative predictive value was 77.4% and the positive predictive value was 44.4%.The CapNoPE parameter is decreased in patients with PE but its diagnostic accuracy seems too low to use in clinical practice.

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Mao, Wenbin, Andrés Caballero, Rebecca T. Hahn, and Wei Sun. "Comparative quantification of primary mitral regurgitation by computer modeling and simulated echocardiography." American Journal of Physiology-Heart and Circulatory Physiology 318, no. 3 (March 1, 2020): H547—H557. http://dx.doi.org/10.1152/ajpheart.00367.2019.

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Clinical investigations have demonstrated that mitral regurgitation (MR) quantification using echocardiography (echo) may significantly underestimate or overestimate the regurgitant volume, especially for two-dimensional (2D) echo. Computer modeling and simulated echo were conducted to evaluate the fundamental assumptions in the echo quantification of primary MR that is due to posterior mitral leaflet prolapse. The theoretical flaw of the proximal isovelocity surface area (PISA) method originates from the assumption that the MR flow rate is the product of the isovelocity surface area and aliasing velocity, which is only valid when the velocity vectors are perpendicular to the isovelocity surface. Other factors such as the Doppler angle effect, the view planes of 2D echo, and the single time instant of PISA were also analyzed. We find that the hemielliptic PISA method gives the smallest error for moderate and severe MR cases compared with other PISA methods. Compared with the PISA method, the volumetric technique (VT) is theoretically more robust. By considering correction factors that are caused by nonflat velocity profiles and the closing volume of the aortic valve, the accuracy of the VT method can be significantly improved. The corrected volumetric technique provides more accurate results compared with the PISA methods, especially for mild MR. NEW & NOTEWORTHY We evaluate the accuracy of common echocardiography techniques for the quantification of primary mitral regurgitations using computer modeling. The hemielliptic proximal isovelocity surface area (PISA) method gives the smallest error (within 15%) for moderate and severe mitral regurgitation cases compared with other PISA methods. The volumetric method is theoretically more robust than the PISA method. The accuracy of the volumetric method can be improved by a correction factor around 0.7 because of the nonflat velocity profiles and the closing volume of the aortic valve.

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