Artykuły w czasopismach na temat „Augmented Metrology”
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Sprawdź 22 najlepszych artykułów w czasopismach naukowych na temat „Augmented Metrology”.
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Poon, Ting-Chung, Yaping Zhang, Liangcai Cao i Hiroshi Yoshikawa. "Editorial on Special Issue “Holography, 3-D Imaging and 3-D Display”". Applied Sciences 10, nr 20 (11.10.2020): 7057. http://dx.doi.org/10.3390/app10207057.
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Modern holographic techniques have been successfully applied in many important areas, such as 3D inspection, 3D microscopy, metrology and profilometry, augmented reality, and industrial informatics [...]
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Siv, Julie, Rafael Mayer, Guillaume Beaugrand, Guillaume Tison, Rémy Juvénal i Guillaume Dovillaire. "Testing and characterization of challenging optics and optical systems with Shack Hartmann wavefront sensors". EPJ Web of Conferences 215 (2019): 06003. http://dx.doi.org/10.1051/epjconf/201921506003.
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The Shack-Hartman wavefront sensor is a common metrology tool in the field of laser, adaptive optics and astronomy. However, this technique is still scarcely used in optics and optical system metrology. With the development of manufacturing techniques and the increasing need for optical characterization in the industry, the Shack-Hartmann wavefront sensor emerges as an efficient complementary tool to the well-established Fizeau interferometry for optical system metrology. Moreover, the raise of smart vehicles equipped with optical sensors and augmented reality, the optical characterization of glass and transparent flat materials becomes an issue that can be addressed with Shack-Hartmann sensors. Aberration measurements of challenging optics will be presented such as optical filters, thin flat optics, aspheric lenses and large optical assemblies.
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Nawab, Rahma, i Angela Davies Allen. "Low-Cost AR-Based Dimensional Metrology for Assembly". Machines 10, nr 4 (30.03.2022): 243. http://dx.doi.org/10.3390/machines10040243.
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The goal of this study was to create and demonstrate a system to perform fast and inexpensive quality dimensional inspection for industrial assembly line applications with submillimeter uncertainty. Our focus is on the positional errors of the assembled pieces on a larger part as it is assembled. This is achieved by using an open-source photogrammetry architecture to gather a point cloud data of an assembled part and then comparing this to a computer-aided design (CAD) model. The point cloud comparison to the CAD model is used to quantify errors in position using the iterative closest point (ICP) algorithm. Augmented reality is utilized to view the errors in a live-video feed and effectively display said errors. The initial demonstration showed an assembled position error of 9 mm ± 0.4 mm for a 40-mm high post.
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Kerst, Thomas, Mohammad Bitarafan, Laura Jokinen, Ilkka Alasaarela, Seppo Tillanen, David Zautasvili i Nikhil Pachhandara. "82‐3: Rapid AR/VR Device Eye‐Box Measurement Using a Wide‐FOV Lens". SID Symposium Digest of Technical Papers 54, nr 1 (czerwiec 2023): 1155–57. http://dx.doi.org/10.1002/sdtp.16779.
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We present a method to rapidly and accurately measure the eye box of Augmented Reality (AR) and Virtual Reality (VR) eyewear. We demonstrate that this rapid method measures the eye box with a fidelity comparable to slower, traditional methods. The presented rapid method uses a lens that mimics the human eye in core aspects like pupil position, pupil size and field of view to get an impression of the eyewear performance as it appears to a human user with single image capture. By combining as few as three such image captures with such a lens, one can rapidly and accurately measure the entire eye box geometry of any given AR or VR eyewear. We further demonstrate the advantages of adopting this new method by referencing the display metrology industry, where this method has already been adopted as the new metrology standard.
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Arpaia, Pasquale, Egidio De Benedetto, Concetta Anna Dodaro, Luigi Duraccio i Giuseppe Servillo. "Metrology-Based Design of a Wearable Augmented Reality System for Monitoring Patient’s Vitals in Real Time". IEEE Sensors Journal 21, nr 9 (1.05.2021): 11176–83. http://dx.doi.org/10.1109/jsen.2021.3059636.
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Gonçalves, GL, JU Delgado i FB Razuck. "The use of Augmented Reality for the teaching of dosimetry and metrology of ionizing radiation at IRD". Journal of Physics: Conference Series 1826, nr 1 (1.03.2021): 012041. http://dx.doi.org/10.1088/1742-6596/1826/1/012041.
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Ho, P. T., J. A. Albajez, J. A. Yagüe i J. Santolaria. "Preliminary study of Augmented Reality based manufacturing for further integration of Quality Control 4.0 supported by metrology". IOP Conference Series: Materials Science and Engineering 1193, nr 1 (1.10.2021): 012105. http://dx.doi.org/10.1088/1757-899x/1193/1/012105.
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Abstract Augmented Reality (AR) is a key technology enabling Industry 4.0, which enriches human perspectives by overlaying digital information onto the real world. The maturity of AR technology has grown recently. As processes in the automotive and aeronautic sectors require high quality and near-zero error rates to ensure the safety of end-users, AR can be implemented to facilitate workers with immersive interfaces to enhance productivity, accuracy and autonomy in the quality sector. In order to analyse whether there is a real and growing interest in the use of AR as assisting technology for manufacturing sector in general and quality control in particular, two specific research questions are defined. In addition, two well-known research databases (Scopus, Web of Science) are used for the paper selection phase in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology to conduct a preliminary study and evaluate the current development of AR applications in manufacturing sector in order to answer the defined questions. It is found that while the development of AR technology has widely implemented to assign real-time information to several systems and processes in assembly and maintenance sectors, this tendency has only emerged in the quality sector over the last few years. However, AR-based quality control has proved its advantages in improving productivity, accuracy and precision of operators as well as benefits to manufacturing in terms of product and process quality control across different manufacturing phases.
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Zhao, Lei, i Chaohao Wang. "50.2: Invited Paper: A Closer Look: Advancements in Near‐Eye Display Testing and Metrology". SID Symposium Digest of Technical Papers 54, S1 (kwiecień 2023): 354–60. http://dx.doi.org/10.1002/sdtp.16303.
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This paper discusses the importance of optical testing metrology for near‐eye displays (NED) used in virtual reality (VR) and augmented reality (AR) environments. The accuracy of parameters such as resolution, contrast, field of view, and color accuracy is critical to the effectiveness of NED. However, existing testing methods for these parameters may not consider the visual characteristics of NED. The paper proposes innovative testing methods for evaluating contrast, pupil swim, and pixel per degree (PPD) in NED. The proposed ANSI contrast test method is found to be more suitable for evaluating the contrast of VR headsets than traditional methods. The paper also proposes two advanced PPD testing methods that take into account lens design and image rendering, providing a more accurate and comprehensive evaluation of pixel distribution on screens at different viewing angles. These testing methods have the potential to improve the development of high‐resolution displays and advance our understanding of the perception of visual stimuli.
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Prusakov, A. N., V. V. Popadyev i V. F. Pankin. "The Working Week of the International Federation of Surveyors under the motto “From digitalization to augmented reality”". Geodesy and Cartography 926, nr 8 (20.09.2017): 25–38. http://dx.doi.org/10.22389/0016-7126-2017-926-8-25-38.
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The information on the last regular Working week, International Federation of Surveyors (FIG) 2017 hold in May-June 2017 in Helsinki (Finland) was given. The article reflects a brief summary of the scientific program of the Working week, which was implemented in the framework of 3 Plenary sessions and 10 technical committees of the International Federation of surveyors (FIG). Also, within sectional meetings organized by the FIG together with its partners, for example, the World Bank and FIG, and the Inspirational Short Sessions (ISS). Information on the technical exhibition, attended by 24 manufacturers of survey equipment, software and accessories is provided. The main areas of developing geodetic science, production and education, and suggested ways of integration by scientists and specialists of the FSBE “Centre of geodesy, cartography and SDI” in the activities of the International Federation of surveyors (FIG) were summarized. The information on the working meeting between the delegation of the FSBE "Centre of geodesy, cartography and SDI" and Finnish Geospatial Research Institute of data on scientific and technical cooperation between the two organizations in the field of geodesy, gravimetry, geodynamics, metrology and standardization was given.
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Ćirić, Ivan, Milan Banić, Miloš Simonović, Aleksandar Miltenović, Dušan Stamenković i Vlastimir Nikolić. "TOWARDS MACHINE VISION BASED RAILWAY ASSETS PREDICTIVE MAINTENANCE". Facta Universitatis, Series: Automatic Control and Robotics 19, nr 2 (8.12.2020): 125. http://dx.doi.org/10.22190/fuacr2002125c.
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The main goal of this paper is to present novel technologies that can contribute to safety, competitiveness, efficiency and operational reliability of Railway infrastructure through the development of innovative solutions for measuring and monitoring of railway assets based on machine vision. Measuring the transversal position of the wheels on the rail, as well as identification of the defects of the wheel and the rail (such as deformation of rail head edge, lateral wear, worn wheels, cracks in wheel and rail, rolling contact fatigue, corrugation and other irregularities) can increase reliability and lower maintenance costs. Currently, there is a need on the market for the innovative solution, namely the on-board high-speed stereo camera system augmented with a system that projects custom pattern (fringe scanner system) for measuring the transversal position of the wheels on the rail, robust to environmental conditions and waste along the track that can provide reliable measurements of transversal position of the wheels up to 200 km/h. New trends in Precise Industrial 3D Metrology are showing that stereo vision is an absolute must have in modern specialized optical precision measuring systems for the three-dimensional coordinate measurement.
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Fisher, William P. "Bateson and Wright on Number and Quantity: How to Not Separate Thinking from Its Relational Context". Symmetry 13, nr 8 (3.08.2021): 1415. http://dx.doi.org/10.3390/sym13081415.
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As part of his explication of the epistemological error made in separating thinking from its ecological context, Bateson distinguished counts from measurements. With no reference to Bateson, the measurement theory and practice of Benjamin Wright also recognizes that number and quantity are different logical types. Describing the confusion of counts and measures as schizophrenic, like Bateson, Wright, a physicist and certified psychoanalyst, showed mathematically that convergent stochastic processes informing counts are predictable in ways that facilitate methodical measurements. Wright’s methods experimentally evaluate the complex symmetries of nonlinear and stochastic numeric patterns as a basis for estimating interval quantities. These methods also retain connections with locally situated concrete expressions, mediating the data display by contextualizing it in relation to the abstractly communicable and navigable quantitative unit and its uncertainty. Decades of successful use of Wright’s methods in research and practice are augmented in recent collaborations of metrology engineers and psychometricians who are systematically distinguishing numeric counts from measured quantities in new classes of knowledge infrastructure. Situating Wright’s work in the context of Bateson’s ideas may be useful for infrastructuring new political, economic, and scientific outcomes.
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Ho, Phuong Thao, José Antonio Albajez, Jorge Santolaria i José A. Yagüe-Fabra. "Study of Augmented Reality Based Manufacturing for Further Integration of Quality Control 4.0: A Systematic Literature Review". Applied Sciences 12, nr 4 (13.02.2022): 1961. http://dx.doi.org/10.3390/app12041961.
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Augmented Reality (AR) has gradually become a mainstream technology enabling Industry 4.0 and its maturity has also grown over time. AR has been applied to support different processes on the shop-floor level, such as assembly, maintenance, etc. As various processes in manufacturing require high quality and near-zero error rates to ensure the demands and safety of end-users, AR can also equip operators with immersive interfaces to enhance productivity, accuracy and autonomy in the quality sector. However, there is currently no systematic review paper about AR technology enhancing the quality sector. The purpose of this paper is to conduct a systematic literature review (SLR) to conclude about the emerging interest in using AR as an assisting technology for the quality sector in an industry 4.0 context. Five research questions (RQs), with a set of selection criteria, are predefined to support the objectives of this SLR. In addition, different research databases are used for the paper identification phase following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) methodology to find the answers for the predefined RQs. It is found that, in spite of staying behind the assembly and maintenance sector in terms of AR-based solutions, there is a tendency towards interest in developing and implementing AR-assisted quality applications. There are three main categories of current AR-based solutions for quality sector, which are AR-based apps as a virtual Lean tool, AR-assisted metrology and AR-based solutions for in-line quality control. In this SLR, an AR architecture layer framework has been improved to classify articles into different layers which are finally integrated into a systematic design and development methodology for the development of long-term AR-based solutions for the quality sector in the future.
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Abbasi, W. A., S. C. Ridgeway, P. D. Adsit, C. D. Crane i J. Duffy. "Investigation of a Special 6-6 Parallel Platform for Contour Milling". Journal of Manufacturing Science and Engineering 122, nr 1 (1.01.1998): 132–39. http://dx.doi.org/10.1115/1.538927.
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Recently, companies have been experimenting with parallel-mechanism based approaches for milling machines. This research presents an investigation into the development of a special 6-6 parallel mechanism for application to contour milling. The idea behind this approach is that existing non-CNC milling equipment can be augmented to increase its capability at a lower cost than purchasing traditional 5-axis machining centers. This paper presents the phase of research associated with developing a parametric kinestatic design methodology for a special 6-6 parallel mechanism (Kinestatic Platform, KP). This methodology was applied to the design specifications associated with 5-axis contour milling. The resulting kinestatic design’s dynamics were evaluated to determine the actuation requirements of each connector. A prototype connector was built to allow the evaluation of actuator response under simulated loading conditions. Joint stiffness and control strategy were of primary concern in evaluating the performance of the prototype connector. The parametric kinestatic design and control strategy results are presented. Several observations are evidenced from the research. Joint deflection is an obvious critical issue and the most difficult to quantify. A scheme is proposed detailing the concept of using a separate metrology frame to overcome difficulties associated with accurate connector length determination. [S1087-1357(00)70101-8]
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Anderson, Stephen A. "Innovative digital inspection methodology". APPEA Journal 60, nr 1 (2020): 77. http://dx.doi.org/10.1071/aj19109.
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The paper describes an innovative digital inspection methodology that combines 3D laser scanning, metrology and advanced non-destructive testing data that is merged in 3D space to provide a digital record of the condition and mechanical integrity of critical assets. This advanced inspection method supports condition-based maintenance programs and digital twin models to determine future equipment condition, work scope and inspection schedules, while maintaining a digital record throughout the equipment lifecycle. Testing of the methodology includes 3D scanning of drill platforms, baseline scanning of blowout preventers and sheaves, for quality purposes, and the use of augmented reality for viewing scans. Phased array testing has been conducted on sub-components such as slew ring bolting. Data are combined into digital reports that show 3D images of the equipment with precise dimensional data and identified inspection areas. Such reports can be combined with digital twin models to confirm integrity of the equipment for certificate of conformance and baseline data for future integrity comparisons as equipment ages. This innovative inspection methodology will set a new standard for how equipment data are captured, stored and represented. The process provides a range of benefits for OEMs, drilling contractors and operators alike, including digital quality programs to baseline new equipment condition and compare with design parameters, delivering condition and integrity assessments of critical equipment items in-situ or on deck, providing a consistent methodology for inspection and dimensional control of operational equipment items, and providing precise equipment data that can complement digital twin and real time monitoring programs.
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Lee, Dong Hun, Yuxuan Zhang, Kwangsoo No, Han Wook Song i Sunghwan Lee. "(Digital Presentation) Multimodal Encapsulation of p-SnOx to Engineer the Carrier Density for Thin Film Transistor Applications". ECS Meeting Abstracts MA2022-02, nr 15 (9.10.2022): 821. http://dx.doi.org/10.1149/ma2022-0215821mtgabs.
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It has been challenging to synthesize p-type SnOx (1≤x<2) and engineer the electrical properties such as carrier density and mobility due to the narrow processing window and the localized oxygen 2p orbitals near the valence band. We recently reported on the processing of p-type SnOx and an oxide-based p-n heterostructures, demonstrating high on/off rectification ratio (>103), small turn-on voltage (<0.5 V), and low saturation current (~1×10-10 A)1. In order to further understand the p-type oxide and engineer the properties for various electronic device applications, it is important to identify (or establish) the dominating doping and transport mechanisms. The low dopability in p-type SnOx, of which the causation is also closely related to the narrow processing window, needs to be mitigated so that the electrical properties of the material are to be adequately engineered 2, 3. Herein, we report on the multifunctional encapsulation of p-SnOx to limit the surface adsorption of oxygen and selectively permeate hydrogen into the p-SnOx channel for thin film transistor (TFT) applications. Time-of-flight secondary ion mass spectrometry measurements identified that ultra-thin SiO2 as a multifunctional encapsulation layer effectively suppressed the oxygen adsorption on the back channel surface of p-SnOx and augmented hydrogen density across the entire thickness of the channel. Encapsulated p-SnOx-based TFTs demonstrated much-enhanced channel conductance modulation in response to the gate bias applied, featuring higher on-state current and lower off-state current. The relevance between the TFT performance and the effects of oxygen suppression and hydrogen permeation is discussed in regard to the intrinsic and extrinsic doping mechanisms. These results are supported by density-functional-theory calculations. Acknowledgement This work was supported by the U.S. National Science Foundation (NSF) Award No. ECCS-1931088. S.L. and H.W.S. acknowledge the support from the Improvement of Measurement Standards and Technology for Mechanical Metrology (Grant No. 20011028) by KRISS. K.N. was supported by Basic Science Research Program (NRF-2021R11A1A01051246) through the NRF Korea funded by the Ministry of Education. References Lee, D. H.; Park, H.; Clevenger, M.; Kim, H.; Kim, C. S.; Liu, M.; Kim, G.; Song, H. W.; No, K.; Kim, S. Y.; Ko, D.-K.; Lucietto, A.; Park, H.; Lee, S., High-Performance Oxide-Based p–n Heterojunctions Integrating p-SnOx and n-InGaZnO. ACS Applied Materials & Interfaces 2021, 13 (46), 55676-55686. Hautier, G.; Miglio, A.; Ceder, G.; Rignanese, G.-M.; Gonze, X., Identification and design principles of low hole effective mass p-type transparent conducting oxides. Nat Commun 2013, 4. Yim, K.; Youn, Y.; Lee, M.; Yoo, D.; Lee, J.; Cho, S. H.; Han, S., Computational discovery of p-type transparent oxide semiconductors using hydrogen descriptor. npj Computational Materials 2018, 4 (1), 17. Figure 1
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Engel, Thomas. "3D-optical measurement techniques". Measurement Science and Technology, 2.12.2022. http://dx.doi.org/10.1088/1361-6501/aca818.
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Abstract The field of optical 3D metrology is gaining significant interest in the past years. Optical sensors can probe the geometry of workpieces and biological samples very fast, highly accurate and without any tactile physical contact to the object’s surface. In this respect, optical sensors are a pre-requisite for many applications in the big trends like Industrial Internet of Things (IIoT), Industry 4.0 or Medicine 4.0. The interest for optical 3D metrology is shifting from a metrology for quality assurance in industrial production to “digitize the real world“ to facilitate a precise digital representation of an object or an environment for documentation or as input data for virtual applications like digital fab or augmented reality. The aspiration to digitize the world necessitates fast and efficient contact free sensing principles of appropriate accuracy for solid and even soft objects with a variety of colour, surface texture and lighting conditions. This review article tries to give a concise conceptual overview about the evolution of a broad variety of optical measurement principles that evolved and gained some importance in the field of 3D metrology for industrial 3D applications and their related technological enablers.
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Nguyen, Vinh, Xiaofeng Liu i Jeremy Marvel. "Augmented Reality Interface for Robot-Sensor Coordinate Registration". Journal of Computing and Information Science in Engineering, 8.08.2023, 1–7. http://dx.doi.org/10.1115/1.4063131.
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Abstract Accurate registration of Cartesian coordinate systems is necessary to facilitate metrology-based solutions for industrial robots in production environments. Conducting coordinate registration between industrial robots and their metrological systems requires measuring multiple points in the robot's and sensor system's coordinate frames. However, operators lack intuitive tools to interface, visualize, and characterize the quality of the selected points in the robot workspace for robot-sensor coordinate registration. This paper proposes an augmented reality system for human-in-the-loop, robot-sensor coordinate registration to efficiently record and visualize the pose-dependent quality of computing the robot-sensor transformation. Furthermore, this work establishes metrics to define the relative quality of measurement points used in robot-sensor coordinate registration, which are shown by the augmented reality application. Experiments were conducted demonstrating the augmented reality environment in addition to investigating the pose-dependency of the measurement point quality. The results indicate that the proposed metrics highlight the dependency of the poses on both robot and sensor placement and that the augmented reality system can provide a human-in-the-loop interface for robot-sensor coordinate registration.
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Schen, Michael A., G. T. Davis, F. I. Mopsik, W. L. Wu, W. E. Wallace, Jr Manning, C. A. Handwerker i D. T. Read. "Electronics Packaging Materials Research at NIST". MRS Proceedings 390 (1995). http://dx.doi.org/10.1557/proc-390-19.
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ABSTRACTThe Materials Science and Engineering Laboratory at NIST has augmented its laboratory-based research in support of the U.S. commercial microelectronics industry by expanding its efforts in electronics packaging, interconnection and assembly (P/I/A) materials technologies. In conjunction with industry, university and other government agency partners, these new NIST efforts target materials technology issues that underlie the priorities contained within the various electronics industry technology roadmaps. A dominant aspect of the laboratory P/I/A program focuses on the in-situ metrology and data needs associated with the materials and complex material assemblies which comprise today's microelectronic components and circuits.
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Tóbiás, Roland, Tibor Furtenbacher, Irén Simkó, Attila G. Császár, Meissa L. Diouf, Frank M. J. Cozijn, Joey M. A. Staa, Edcel J. Salumbides i Wim Ubachs. "Spectroscopic-network-assisted precision spectroscopy and its application to water". Nature Communications 11, nr 1 (6.04.2020). http://dx.doi.org/10.1038/s41467-020-15430-6.
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AbstractFrequency combs and cavity-enhanced optical techniques have revolutionized molecular spectroscopy: their combination allows recording saturated Doppler-free lines with ultrahigh precision. Network theory, based on the generalized Ritz principle, offers a powerful tool for the intelligent design and validation of such precision-spectroscopy experiments and the subsequent derivation of accurate energy differences. As a proof of concept, 156 carefully-selected near-infrared transitions are detected for H216O, a benchmark system of molecular spectroscopy, at kHz accuracy. These measurements, augmented with 28 extremely-accurate literature lines to ensure overall connectivity, allow the precise determination of the lowest ortho-H216O energy, now set at 23.794 361 22(25) cm−1, and 160 energy levels with similarly high accuracy. Based on the limited number of observed transitions, 1219 calibration-quality lines are obtained in a wide wavenumber interval, which can be used to improve spectroscopic databases and applied to frequency metrology, astrophysics, atmospheric sensing, and combustion chemistry.
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Murray, Myles P., Laura S. Bruckman i Roger H. French. "Durability of Materials in a Stress-Response Framework: Acrylic Materials for Photovoltaic Systems". MRS Proceedings 1391 (2012). http://dx.doi.org/10.1557/opl.2012.1241.
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ABSTRACTIn the development of novel materials for enhanced photovoltaic (PV) performance, it is critical to have quantitative knowledge of the initial performance, as well as the performance of these materials over the required 25-year lifetime of the PV system. Lifetime and degradation science (L&DS) allows for the development of new metrology and metrics, coupled to degradation mechanisms and rates. Induced absorbance to dose (IAD), a new metric being developed for solar radiation durability studies of solar and environmentally exposed photovoltaic materials, is defined as the rate of photodarkening or photobleaching of a material as a function of total absorbed solar radiation dose. In a reliability engineering framework, these quantitative degradation rates can be determined at various solar irradiances making possible real time and accelerated testing. The potential to predict power losses in a photovoltaic system over time caused by the accumulation of this kind of degradation can be calculated for real time applications or extrapolated for accelerated exposure conditions. Three formulations of poly (methyl methacrylate) (PMMA) used for mirror augmented PV systems were analyzed for the changes in IAD after accelerated testing.
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Juethner, Konrad, Ted Rose, Senthil Kumar, Jianming Cao, Gregory Savela, Chris J. Zuck i Parag Mathuria. "Finite Element Analysis of Bent Rotors". Journal of Engineering for Gas Turbines and Power, 2.09.2022. http://dx.doi.org/10.1115/1.4055452.
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Abstract The rotor assembly of an engine is typically designed around a straight centerline. However, every manufactured rotor is bent once it undergoes careful quality inspection. Bent and bowed rotors are similar but differ in that bends are permanent, whereas rotor bow is temporary and observed in the mounted rotor assembly. The presence of bends leads to force and moment distributions along the rotor that can have dynamic implications. Unlike unbalance loads, the rotating excitation of a bent rotor remains constant. Although bent rotors are defined in the literature, their analysis is confined to simplified cases where centerline deviations at the bearing supports are zero. For realistic rotors, an additional static analysis is required to obtain the proper dynamic load distribution. Here, the finite element method is used to analyze bent rotors within an MSC NASTRAN workflow to evaluate bent rotors of any complexity. This approach can account for static, compliant, and greatly featured support structures with misaligned bearing supports. Angular and lateral offsets are explored with increasing complexity where force and moment distributions are computed to subsequently excite the bent rotor dynamically. This method can be deployed in combination with high-tech metrology equipment that can produce many measurements. In a final step, the bent rotor is augmented with unbalances and compared to its nominal counterpart to deliver the motivation for this method and its value to the turbomachinery community. All results are verified against an experimentally validated transfer matrix method.
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Zhang, Wen-Hao, Jing-Wei Yu, Wule Zhu i Bing-Feng Ju. "Unified framework for geometric error compensation and shape-adaptive scanning in five-axis metrology systems". Measurement Science and Technology, 16.05.2024. http://dx.doi.org/10.1088/1361-6501/ad4c83.
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Abstract In response to the escalating demand for precise shape metrology of complex optical surfaces, this study unveils a unified geometric error compensation and trajectory planning framework tailored for high-accuracy five-axis scanning metrology systems, which remains a notably underexplored field compared to error compensation in machine tools. Founded on a unified geometric model, the proposed framework seamlessly integrates a versatile shape-adaptive trajectory planning strategy, a thorough global error sensitivity analysis approach, and an exhaustive geometric error compensation scheme. Leveraging inverse kinematics, an innovative shape-adaptive scanning trajectory generation strategy is mathematically formulated, thereby facilitating adaptable measurement trajectory generation for diverse surface geometries. Employing forward kinematics, an exhaustive geometric error model is established to extensively address the 53 distinct geometric errors in the metrology system. This proposed error model fundamentally augments conventional geometric error models in machine tool by managing not only the geometric errors from the motion system, but also those from the probe and workpiece. To streamline the error compensation procedure, a novel global error sensitivity analysis approach is introduced, identifying both system-oriented and process-oriented sensitive geometric errors for targeted compensation. Experimental validation using a standard ball, which achieved an exceptional 89.35% reduction in the root mean square (RMS) of the measurement errors, further confirms the feasibility and effectiveness of the proposed framework. By offering an universal trajectory planning, sensitivity analysis and error compensation trinity for five-axis scanning metrology systems, this study sets the stage for precision advancements and design optimization across diverse configurations of metrology systems.