Journal articles: 'Vertical misfit'

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Abasolo, Mikel, Josu Aguirrebeitia, Javier Vallejo, Joseba Albizuri, and Ibai Coria. "Influence of vertical misfit in screw fatigue behavior in dental implants: A three-dimensional finite element approach." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 232, no. 11 (2018): 1117–28. http://dx.doi.org/10.1177/0954411918806325.

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Misfit is unavoidable in dental implant-supported prostheses due to machining process or inappropriate assembling, and the definition of an admissible misfit is still a controversial issue. This work aims to understand the behavior of the screws in dental implant-supported prostheses to estimate an admissible vertical misfit value in terms of screw fatigue failure. For that purpose, a finite element model of a dental implant-supported prosthesis was created and analyzed. Vertical misfits were introduced in different positions, the lower and upper screws were tightened to the bolting force values recommended by the manufacturer, and two different occlusal loads were analyzed. In addition, two different prosthesis materials were studied. Screw load variations were reported and a fatigue analysis was performed. As a result, it was observed that the screw tightening sequence closed small vertical misfits (equal to or less than 40 µm), whereas larger misfits (more than 40 µm) remained open. If the vertical misfit is closed by the end of the tightening sequence, it may be considered equivalent to the ideal fit situation in regard to screw fatigue failure. The prosthesis material had no significant influence on the fatigue behavior.

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Barbosa, Gustavo Augusto Seabra, Sérgio Rocha Bernardes, Flávio Domingues das Neves, Alfredo Júlio Fernandes Neto, Maria da Glória Chiarello de Mattos, and Ricardo Faria Ribeiro. "Relation between implant/abutment vertical misfit and torque loss of abutment screws." Brazilian Dental Journal 19, no. 4 (2008): 358–63. http://dx.doi.org/10.1590/s0103-64402008000400013.

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This study investigated whether there is a direct correlation between the level of vertical misfit at the abutment/implant interface and torque losses (detorque) in abutment screws. A work model was obtained from a metal matrix with five 3.75 x 9 mm external hex implants with standard platform (4.1 mm). Four frameworks were waxed using UCLA type abutments and one-piece cast in commercially pure titanium. The misfit was analyzed with a comparator microscope after 20 Ncm torque. The highest value of misfit observed per abutment was used. The torque required to loose the screw was evaluated using a digital torque meter. The torque loss values, measured by the torque meter, were assumed as percentage of initial torque (100%) given to abutment screws. Pearson's correlation (α=0.05) between the misfit values (29.08 ± 8.78 µm) and the percentage of detorque (50.71 ± 11.37%) showed no statistically significant correlation (p=0.295). Within the limitations of this study, it may be concluded that great vertical misfits dot not necessarily implies in higher detorque values.

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Pereira, Lorena M. S., Mariane B. Sordi, Ricardo S. Magini, Antônio R. Calazans Duarte, and Júlio C. M. Souza. "Abutment misfit in implant-supported prostheses manufactured by casting technique: An integrative review." European Journal of Dentistry 11, no. 04 (2017): 553–58. http://dx.doi.org/10.4103/ejd.ejd_162_17.

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ABSTRACTThe aim of this study was to perform an integrative review of the literature on the clinically usual prosthesis-abutment misfit over implant-supported structures manufactured by conventional casting technique. The present integrative review used the PRISMA methodology. A bibliographical search was conducted on the following electronic databases: MEDLINE/PubMed (National Library of Medicine), Scopus (Elsevier), ScienceDirect (Elsevier), Web of Science (Thomson Reuters Scientific), Latin American and Caribbean Center on Health Sciences Information (BIREME), and Virtual Health Library (BVS). A total of 11 relevant studies were selected for qualitative analysis. The prosthetic-abutment vertical misfit considered clinically usual ranged from 50 to 160 μm. The vertical misfit depends on several steps during technical manufacturing techniques, which includes the materials and technical procedures. Lower values in misfit are recorded when precious metal or titanium alloys are utilized. Although a vertical misfit mean value of 100 μm has been considered clinically usual, most of the previous studies included in this revision showed lower mean values.

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Irakarama, Modeste, Paul Cupillard, Guillaume Caumon, Paul Sava, and Jonathan Edwards. "Appraising structural interpretations using seismic data — Theoretical elements." GEOPHYSICS 84, no. 2 (2019): N29—N40. http://dx.doi.org/10.1190/geo2018-0128.1.

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Structural interpretation of seismic images can be highly subjective, especially in complex geologic settings. A single seismic image will often support multiple geologically valid interpretations. However, it is usually difficult to determine which of those interpretations are more likely than others. We have referred to this problem as structural model appraisal. We have developed the use of misfit functions to rank and appraise multiple interpretations of a given seismic image. Given a set of possible interpretations, we compute synthetic data for each structural interpretation, and then we compare these synthetic data against observed seismic data; this allows us to assign a data-misfit value to each structural interpretation. Our aim is to find data-misfit functions that enable a ranking of interpretations. To do so, we formalize the problem of appraising structural interpretations using seismic data and we derive a set of conditions to be satisfied by the data-misfit function for a successful appraisal. We investigate vertical seismic profiling (VSP) and surface seismic configurations. An application of the proposed method to a realistic synthetic model shows promising results for appraising structural interpretations using VSP data, provided that the target region is well-illuminated. However, we find appraising structural interpretations using surface seismic data to be more challenging, mainly due to the difficulty of computing phase-shift data misfits.

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RODRIGUES, Vinícius Anéas, João Paulo Mendes TRIBST, Leandro Ruivo de SANTIS, Gabriela Nogueira de Melo NISHIOKA, Dimas Renó de LIMA, and Renato Sussumu NISHIOKA. "Microscopic evaluation of implant platform adaptation with UCLA-type abutments: in vitro study." Revista de Odontologia da UNESP 46, no. 1 (2017): 56–60. http://dx.doi.org/10.1590/1807-2577.19516.

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Abstract Introduction The fit between abutment and implant is crucial to determine the longevity of implant-supported prostheses and the maintenance of peri-implant bones. Objective To evaluate the vertical misfit between different abutments in order to provide information to assist abutment selection. Material and method UCLA components (N=40) with anti-rotational system were divided as follows: components usinated in titanium (n=10) and plastic components cast proportionally in titanium (n=10), nickel-chromium-titanium-molybdenum (n=10) and nickel-chromium (n=10) alloys. All components were submitted to stereomicroscope analysis and were randomly selected for characterization by SEM. Result Data were analyzed using mean and standard deviation and subjected to ANOVA-one way, where the groups proved to statistically different (p=<0.05), followed by Tukey’s test. Conclusion The selection of material influences the value of vertical misfit. The group machined in Ti showed the lowest value while the group cast in Ni Cr showed the highest value of vertical misfit.

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Pan, Wenyong, and Kristopher A. Innanen. "Amplitude-based misfit functions in viscoelastic full-waveform inversion applied to walk-away vertical seismic profile data." GEOPHYSICS 84, no. 5 (2019): B335—B351. http://dx.doi.org/10.1190/geo2018-0765.1.

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Viscoelastic full-waveform inversion is applied to walk-away vertical seismic profile data acquired at a producing heavy-oil field in Western Canada for the determination of subsurface velocity models (P-wave velocity [Formula: see text] and S-wave velocity [Formula: see text]) and attenuation models (P-wave quality factor [Formula: see text] and S-wave quality factor [Formula: see text]). To mitigate strong velocity-attenuation trade-offs, a two-stage approach is adopted. In Stage I, [Formula: see text] and [Formula: see text] models are first inverted using a standard waveform-difference (WD) misfit function. Following this, in Stage II, different amplitude-based misfit functions are used to estimate the [Formula: see text] and [Formula: see text] models. Compared to the traditional WD misfit function, the amplitude-based misfit functions exhibit stronger sensitivity to attenuation anomalies and appear to be able to invert [Formula: see text] and [Formula: see text] models more reliably in the presence of velocity errors. Overall, the root-mean-square amplitude-ratio and spectral amplitude-ratio misfit functions outperform other misfit function choices. In the final outputs of our inversion, significant drops in the [Formula: see text] to [Formula: see text] ratio (~1.6) and Poisson’s ratio (~0.23) are apparent within the Clearwater Formation (depth ~0.45–0.50 km) of the Mannville Group in the Western Canada Sedimentary Basin. Strong [Formula: see text] (~20) and [Formula: see text] (~15) anomalies are also evident in this zone. These observations provide information to help identify the target attenuative reservoir saturated with heavy-oil resources.

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Pellizzer1, Eduardo Piza, Caroline Cantieri de Mello, Jéssica Marcela de Luna Gomes, Joel Ferreira Santiago Júnior, Cleidiel Aparecido Araújo Lemos, and Fellippo Ramos Verri. "Vertical and Horizontal Misfit Analysis of 3-unit FDP Fabricated with Different Techniques and CAD/CAM Systems." Brazilian Dental Journal 29, no. 4 (2018): 342–46. http://dx.doi.org/10.1590/0103-6440201801916.

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Abstract The aim of this is was evaluate the vertical and horizontal marginal adaptation of 3-unit fixed partial denture frameworks fabricated using different techniques and CAD/CAM systems. A total of 40 framework specimens were fabricated and divided into four groups as follows: lost-wax casting (G1); lost-wax casting with welding (G2); extraoral optical scanning of models (3S/DWOS) (G3); intraoral optical scanning (Cerec Bluecam/Sirona) (G4). A reference model was used to simulate a fixed partial denture with three elements (with a central pontic). The frameworks of G1 and G2 were cast in nickel-chromium (NiCr) alloy, whereas those of G3 and G4 were milled in zirconia. In all groups, vertical and horizontal marginal adaptation (over-contour and under-contour) was evaluated using a three-dimensional optical microscope (Quick Scope, Mitutoyo). The results showed higher vertical marginal misfit in G1 than in the other groups (p<0.001). Regarding horizontal marginal misfit, higher over-contour values occurred in G3 than in the other groups (p<0.001). G3 did not show under-contour at all, whereas the other groups did not differ from each other in this regard (p>0.05). Within the limitations of this study, it can be concluded that lost-wax casting with welding is a viable alternative to the use of CAD/CAM systems to fabricate frameworks of three-unit FPDs, since the techniques yielded similar vertical misfit values. Extra-oral CAD/CAM systems showed the highest horizontal misfit (over-contour) compared to other groups.

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Rodrigues, Vinícius Anéas, João Paulo Mendes Tribst, Leandro Ruivo de Santis, Dimas Renó de Lima, and Renato Sussumu Nishioka. "Influence of angulation and vertical misfit in the evaluation of micro-deformations around implants." Brazilian Dental Science 20, no. 1 (2017): 32. http://dx.doi.org/10.14295/bds.2017.v20i1.1311.

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<div>Objective: This in vitro study was to evaluate micro-strains around of implant, under the influence of angulations and vertical misfit in three-element implant-supported fixed partial dentures during axial loading by using strain gauge analysis. Materials and Methods: Three external hexagon implants with straight configuration and three external hexagon implants with angled (17°) configuration were inserted into two polyurethane blocks. To measure micro-strain, four strain gauges were bonded onto the surface of each block. Plastic copings were adapted to a standard wax pattern and cast. An axial load of 30 kgf was applied on the center of each implant for 10 seconds, using a load application device. The vertical misfit was measured at six different points by using a stereo microscope with 100-X magnification. Results: The results showed that the values for different implant angulations were significant (P= 0.0086). The Pearson’s correlation test between micro-strain and vertical misfit revealed no correlation between angled configuration (P= 0.891) and straight configuration (P= 0.568). Conclusion: The micro strain was higher for angled implants; no correlation was found between the vertical misfit and the micro strain values.</div>

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Vasconcellos, Diego Klee de, Marco Antonio Bottino, Renato Sussumu Nishioka, Luiz Felipe Valandro, and Elza Maria Valadares da Costa. "The influence of different screw tightening forces on the vertical misfit of implant-supported frameworks." Journal of Applied Oral Science 13, no. 2 (2005): 120–25. http://dx.doi.org/10.1590/s1678-77572005000200005.

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OBJECTIVES: The present in vitro study was designed to compare the differences in the vertical misfit of implant-supported frameworks using three different forces for tightening the bridge locking screws: fastening by hand until first resistance, and using torque drivers with 10 and 20Ncm. METHODS: The investigation was conducted based on the results given by 9 six-unit nickel-chromium (2 abutments/ 4 pontics) screw-retained implant-supported frameworks. The structures were exposed to simulated porcelain firings. The marginal misfit measurements were made using a traveling measuring microscope at selected screw tightening forces: fastening by hand until first resistance, and using torque drivers with 10 and 20Ncm. The results were submitted to one-way ANOVA with repeated measures on one factor, and post hoc pairwise comparisons using Tukey test (5%). RESULTS: The mean marginal misfit of the frameworks, fastening the screws by hand until first resistance, was 41.56µm (SD±12.45µm). The use of torque driver devices caused a significant reduction in marginal opening (p<0.05). With the lowest torque available (10Ncm), the mean marginal discrepancy at the abutment-framework interface was reduced an average of 52% to a mean marginal opening of 19.71µm (SD±2.97µm). After the use of the 20Ncm torque driver, the mean marginal discrepancy of the frameworks was reduced an average of 69% to a mean marginal opening of 12.82µm (SD±4.0µm). Comparing the use of torque drivers with 10 and 20 Ncm torque, the means are not significantly different from one another. CONCLUSION: The seating force has an important effect on the vertical misfit measurements, once it may considerably narrow the vertical misfit gaps at the abutment-framework interface, thus leading to a misjudgment of the real marginal situation.

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Barbosa Jr, Sales Antônio, Ataís Bacchi, Valentim Adelino Ricardo Barão, et al. "Implant Volume Loss, Misfit, Screw Loosening, and Stress In Custom Titanium and Zirconia Abutments." Brazilian Dental Journal 31, no. 4 (2020): 374–79. http://dx.doi.org/10.1590/0103-6440202003643.

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Abstract The aim of this study was to verify the effect of the implant volume loss, vertical misfit between abutment and prosthetic platform, prosthetic screw loosening torque, and screw stress distribution in titanium and zirconia abutments. Ten CAD/CAM system custom abutments of each material were milled and attached to the titanium implants. The implant volume loss was evaluated by microtomography, the vertical misfit with optical microscopy, and digital torque wrench measured the prosthetic screw loosening. All experimental analyses were performed before and after mechanical cycle (1,000,000 cycles, 100 N/2 Hz). Virtual models of the structures were created for finite element analysis, and the stress on the screw obtained with von Mises procedure. Data were analyzed using an independent t-test, two-way ANOVA for repeated measures, and Tukey’s HSD test (a=0.05). There was no significant difference in the implant volume loss for the two abutment materials (p=0.662). Titanium abutments provided higher loosening torque values after mechanical cycling (p<0.001). Lesser marginal misfit was obtained with titanium abutments before and after mechanical cycling (p<0.001). The stress distribution on the screw was similar between abutment materials. In conclusion, CAD/CAM custom titanium abutment reduced the marginal misfit and increased the torque maintenance of prosthetic screws when compared to CAD/CAM custom zirconia abutment.

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Gomes, E. A., R. F. Ribeiro, R. Tiossi, R. C. S. Rodrigues, and Y. T. Silva-Sousa. "Vertical misfit of CAD/CAM zirconia and titanium frameworks for prosthesis." Dental Materials 30 (2014): e6-e7. http://dx.doi.org/10.1016/j.dental.2014.08.013.

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Barbosa, Gustavo Augusto Seabra, Flávio Domingues das Neves, Maria da Gloria Chiarello de Mattos, Renata Cristina Silveira Rodrigues, and Ricardo Faria Ribeiro. "Implant/abutment vertical misfit of one-piece cast frameworks made with different materials." Brazilian Dental Journal 21, no. 6 (2010): 515–19. http://dx.doi.org/10.1590/s0103-64402010000600006.

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This study compared vertical and passive fit of one-piece cast frameworks made with 3 different materials: commercially pure titanium (CP Ti - G1), cobalt-chromium alloy (Co-Cr - G2) and nickel-chromium-titanium alloy (Ni-Cr-Ti - G3). Fifteen frameworks were obtained simulating bars for fixed prosthesis in a model with 5 implants. The passive and vertical fit of the framework interface was measured using an optical microscope at Ã—30 magnification. Data were statistically analyzed by ANOVA and LSD tests (Î±=0.05). Mean and standard deviation values for passive fit and vertical fit were, respectively: G1 [472.49 (109.88) Âµm and 29.9 (13.24) Âµm], G2 [584.84 (120.20) Âµm and 27.05 (10.30) Âµm], and G3 [462.70 (179.18) Âµm and 24.95 (11.14) Âµm]. For vertical fit, there were no significant differences among G1, G2 and G3 (p=0.285). There were no significant differences for passive fit between G1 and G3 (p=0.844), but both differed significantly from G2 (p=0.028 and p=0.035, respectively), which showed the highest misfit values. It may be concluded that the vertical fit of frameworks was not affected by the tested materials, and that one-piece cast frameworks resulted in inadequate passive fit. The Co-Cr alloy presented the worst values for passive fit.

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Assunção, Wirley Gonçalves, Juliana Aparecida Delben, Lucas Fernando Tabata, Valentim Adelino Ricardo Barão, and Érica Alves Gomes. "Effect of Vertical Misfit on Screw Joint Stability of Implant-Supported Crowns." Journal of Materials Engineering and Performance 20, no. 6 (2010): 947–51. http://dx.doi.org/10.1007/s11665-010-9699-9.

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Mittet, Rune, and Pål Tunbrumo Gabrielsen. "Decomposition in upgoing and downgoing fields and inversion of marine CSEM data." GEOPHYSICS 78, no. 1 (2013): E1—E17. http://dx.doi.org/10.1190/geo2011-0520.1.

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We describe a data-driven method to estimate the top-formation resistivity using marine controlled-source electromagnetic data. The procedure exploits the fact that the airwave contributions are traveling up or down with a Poynting vector close to the vertical axis. The proposed method is based on forming an impedance in the same way as it is done in magnetotelluric processing. The top-formation resistivity is used to perform up-down decomposition of the electric field below the seabed. This procedure suppresses the contribution from the airwave in the resulting upgoing electric field and increases the data sensitivity to the subsurface resistivity distribution. The upgoing electric field is used in the misfit kernel for an inversion scheme. This is a method that is intended for use in shallow water. Inversion using the upgoing electric field means that the observed electric and magnetic fields contribute to the data misfit. The optimization procedure seeks to reduce the misfit between the observed and predicted data for both fields. We compared this procedure with the conventional procedure of predicting electric fields only. The addition of magnetic data improved the resolution for the synthetic and the real data examples. We performed postinversion modeling on the final resistivity models. The weighted misfit of the electric data was added to the weighted misfit of the magnetic data to form the total error. We found that this total error was smallest for the case in which we used the upgoing electric field in the misfit kernel.

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Barbosa, Gustavo Augusto Seabra, Paulo Cézar Simamoto Júnior, Alfredo Júlio Fernandes Neto, Maria da Glória Chiarello de Mattos, and Flávio Domingues das Neves. "Prosthetic laboratory influence on the vertical misfit at the implant/UCLA abutment interface." Brazilian Dental Journal 18, no. 2 (2007): 139–43. http://dx.doi.org/10.1590/s0103-64402007000200010.

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An inadequate fit at the abutment/implant interface can generate mechanical and biological problems. The laboratorial stages could induce misfit in such interface when the castable UCLA abutment type is used. The purpose of this study was to comparatively evaluate the performance of three prosthetic laboratories (Labs A, B and C) by vertical fit analysis of castable UCLA abutments on the casting and soldering stages of the same prosthesis. Four fixed prostheses were built by each laboratory using castable UCLA abutments. The evaluation was made by scanning electron microscopy under 500x magnification in the mesial and distal regions of each element of the prosthesis, totalizing 24 measurements per laboratory. The results were analyzed statistically by Kruskal-Wallis test (p<0.05). In the casting process, the values presented by the laboratories differed significantly to each other (p=0.004). After soldering, the values presented by the laboratories showed no significant difference (p=0.948). It may be concluded that the fit values obtained in the casting stage of UCLA abutments can be influenced when processed by different laboratories, and that conventional soldering itself increased the degree of framework misfit, regardless of which laboratory made it.

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Spazzin, Aloísio Oro, Guilherme Elias Pessanha Henriques, Mauro Antônio de Arruda Nóbilo, Rafael Leonardo Xediek Consani, Lourenço Correr-Sobrinho, and Marcelo Ferraz Mesquita. "Influence of Prosthetic Screw Material on Joint Stability in Passive and Non-Passive Implant-Supported Dentures." Open Dentistry Journal 3, no. 1 (2009): 245–49. http://dx.doi.org/10.2174/1874210600903010245.

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Objectives: This study evaluated the influence of prosthetic screw material on joint stability in implantsupported dentures at two levels of fit. Methods: Ten mandibular implant-supported dentures were fabricated. Twenty cast models were fabricated using these dentures. Four groups (n=10) were tested, according to the vertical fit of the dentures [passive and non-passive] and prosthetic screw materials [titanium (Ti) or gold (Au) alloy]. The one-screw test was performed to quantify the vertical misfits using an optic microscope. The loosening torque for the prosthetic screws was measured 24 hours after the tightening torque (10 Ncm) using a digital torque meter. Data were analyzed by two-way ANOVA and Tukey’s test (α=0.05). Results: Overall, dentures with passive fit and Ti screws resulted in significantly higher loosening torque of the prosthetic screws (p<0.05). No significant interaction was found between fit level and screw material (p=0.199). The prosthetic screw material and fit of implant-supported dentures have an influence on screw joint stability. Ti screws presented higher joint stability than Au screws and minimum of misfit should be found clinically to improve the mechanical behavior of the screw joint.

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Fontoura, Diego, Vinicius Barros, Claúdia de Magalhães, Ricardo Vaz, and Allyson Moreira. "Evaluation of Vertical Misfit of CAD/CAM Implant-Supported Titanium and Zirconia Frameworks." International Journal of Oral & Maxillofacial Implants 33, no. 5 (2018): 1027–32. http://dx.doi.org/10.11607/jomi.6320.

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Feng, Shihang, and Gerard T. Schuster. "Skeletonized wave-equation inversion in vertical symmetry axis media without too much math." Interpretation 5, no. 3 (2017): SO21—SO30. http://dx.doi.org/10.1190/int-2016-0212.1.

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We have developed a tutorial for skeletonized inversion of pseudo-acoustic anisotropic vertical symmetry axis (VTI) data. We first invert for the anisotropic models using wave-equation traveltime inversion. Here, the skeletonized data are the traveltimes of transmitted and/or reflected arrivals that lead to simpler misfit functions and more robust convergence compared with full-waveform inversion. This provides a good starting model for waveform inversion. The effectiveness of this procedure is illustrated with synthetic data examples and a marine data set recorded in the Gulf of Mexico.

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de Jesus Tavarez, Rudys Rodolfo, Wellington Cardoso Bonachela, and Anuar Antônio Xible. "Effect of cyclic load on vertical misfit of prefabricated and cast implant single abutment." Journal of Applied Oral Science 19, no. 1 (2011): 16–21. http://dx.doi.org/10.1590/s1678-77572011000100005.

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Abduo, Jaafar, and Karl Lyons. "Effect of vertical misfit on strain within screw-retained implant titanium and zirconia frameworks." Journal of Prosthodontic Research 56, no. 2 (2012): 102–9. http://dx.doi.org/10.1016/j.jpor.2011.09.001.

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Spazzin, Aloísio O., Ricardo T. Abreu, Pedro Y. Noritomi, Rafael Leonardo X. Consani, and Marcelo F. Mesquita. "Evaluation of Stress Distribution in Overdenture-Retaining Bar with Different Levels of Vertical Misfit." Journal of Prosthodontics 20, no. 4 (2011): 280–85. http://dx.doi.org/10.1111/j.1532-849x.2011.00708.x.

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Moris, Izabela C. M., Silas Borges Monteiro, Raíssa Martins, Ricardo Faria Ribeiro, and Erica A. Gomes. "Influence of Manufacturing Methods of Implant-Supported Crowns on External and Internal Marginal Fit: A Micro-CT Analysis." BioMed Research International 2018 (2018): 1–6. http://dx.doi.org/10.1155/2018/5049605.

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Aim.To evaluate the influence of different manufacturing methods of single implant-supported metallic crowns on the internal and external marginal fit through computed microtomography.Methods.Forty external hexagon implants were divided into 4 groups(n=8), according to the manufacturing method: GC, conventional casting; GI, induction casting; GP, plasma casting; and GCAD, CAD/CAM machining. The crowns were attached to the implants with insertion torque of 30 N·cm. The external (vertical and horizontal) marginal fit and internal fit were assessed through computed microtomography. Internal and external marginal fit data (μm) were submitted to a one-way ANOVA and Tukey’s test(α=.05). Qualitative evaluation of the images was conducted by using micro-CT.Results.The statistical analysis revealed no significant difference between the groups for vertical misfit(P=0.721). There was no significant difference(P>0.05)for the internal and horizontal marginal misfit in the groups GC, GI, and GP, but it was found for the group GCAD(P≤0.05). Qualitative analysis revealed that most of the samples of cast groups exhibited crowns underextension while the group GCAD showed overextension.Conclusions.The manufacturing method of the crowns influenced the accuracy of marginal fit between the prosthesis and implant. The best results were found for the crowns fabricated through CAD/CAM machining.

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Gonzalo, Esther, Beatriz Vizoso, Carlos Lopez-Suarez, Pedro Diaz, Jesus Pelaez, and Maria J. Suarez. "Evaluation of Milled Titanium versus Laser Sintered Co-Cr Abutments on the Marginal Misfit in Internal Implant-Abutment Connection." Materials 13, no. 21 (2020): 4873. http://dx.doi.org/10.3390/ma13214873.

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The precision of fit at the implant-abutment connection is an important criterion for the clinical success of restorations and implants. Several factors are involved among which are the abutment materials and manufacturing techniques. The aim of this study was to investigate the effect of two materials and methods of manufacturing implant abutments, milled titanium versus laser sintered Co-Cr, on the marginal misfit at the implant-abutment interface. Scanning electron microscopes (SEM) were used to geometrically measure the marginal vertical discrepancy of a total of 80 specimens, classified into eight categories, according to the implant system and abutment. The data were statistically analyzed by Student’s paired t test, one-way and two-way ANOVA with the Bonferroni-Holm correction at the significance level of p = 0.05. Milled titanium abutments demonstrated the lowest misfit values in the implant systems analyzed. The marginal fit of all the groups was within the clinically acceptable range for implant prostheses.

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Oyagüe, Raquel Castillo, Andrés Sánchez Turrión, Manuel Toledano, Francesca Monticelli, and Raquel Osorio. "In vitro vertical misfit evaluation of cast frameworks for cement-retained implant-supported partial prostheses." Journal of Dentistry 37, no. 1 (2009): 52–58. http://dx.doi.org/10.1016/j.jdent.2008.09.007.

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Abreu, Ricardo T., Aloísio O. Spazzin, Pedro Y. Noritomi, Rafael Leonardo X. Consani, and Marcelo F. Mesquita. "Influence of Material of Overdenture-Retaining Bar with Vertical Misfit on Three-Dimensional Stress Distribution." Journal of Prosthodontics 19, no. 6 (2010): 425–31. http://dx.doi.org/10.1111/j.1532-849x.2010.00612.x.

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Nogueira, Moises C. F., Atais Bacchi, Marcelo F. Mesquita, Mateus B. F. Santos, and Rafael L. X. Consani. "Influence of Cross-Section Design and Vertical Misfit on Stress Distribution in Overdenture Retaining System." Implant Dentistry 27, no. 4 (2018): 445–51. http://dx.doi.org/10.1097/id.0000000000000770.

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dos Santos, Mateus Bertolini Fernandes, Bruno Massucato Zen, and Atais Bacchi. "Effect of vertical misfit and clip material on stress distribution of overdentures under masticatory loading." Medical & Biological Engineering & Computing 54, no. 10 (2015): 1515–21. http://dx.doi.org/10.1007/s11517-015-1426-0.

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Fitterman, David V., and Changchun Yin. "Effect of bird maneuver on frequency‐domain helicopter EM response." GEOPHYSICS 69, no. 5 (2004): 1203–15. http://dx.doi.org/10.1190/1.1801937.

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Bird maneuver, the rotation of the coil‐carrying instrument pod used for frequency‐domain helicopter electromagnetic surveys, changes the nominal geometric relationship between the bird‐coil system and the ground. These changes affect electromagnetic coupling and can introduce errors in helicopter electromagnetic (HEM) data. We analyze these effects for a layered half‐space for three coil configurations: vertical coaxial, vertical coplanar, and horizontal coplanar. Maneuver effect is shown to have two components: one that is purely geometric and another that is inductive in nature. The geometric component is significantly larger. A correction procedure is developed using an iterative approach that uses standard HEM inversion routines. The maneuver effect correction reduces inversion misfit error and produces laterally smoother cross sections than obtained from uncorrected data.

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Sun, Robert, and George A. McMechan. "Nonlinear reverse‐time inversion of elastic offset vertical seismic profile data." GEOPHYSICS 53, no. 10 (1988): 1295–302. http://dx.doi.org/10.1190/1.1442407.

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An iterative nonlinear inversion algorithm for two‐dimensional elastic media gives estimates of P-velocity and S-velocity distributions from synthetic offset vertical seismic profiles. The algorithm is a hybrid of inversion and principles borrowed from reverse‐time migration. Gradients of the misfit function are dynamically determined by crosscorrelations of the computed incident wave fields with the scattered compressional and shear wave fields. Model perturbations are defined in the steepest descent direction. In order to optimize the sensitivity of the inversion to both compressional and shear velocity distributions, two data collection experiments are required, one with a compressional wave source and the other with a shear wave source. Inversion iterations alternate between the compressional and shear source data sets. In test examples, the new algorithm converges successfully to the correct solution when the starting model’s compressional and shear velocities deviated by as much as 20 percent from the correct solution.

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Raposo, LH, PS Borella, DC Ferraz, LM Pereira, MS Prudente, and PC Santos-Filho. "Influence of Computer-aided Design/Computer-aided Manufacturing Diamond Bur Wear on Marginal Misfit of Two Lithium Disilicate Ceramic Systems." Operative Dentistry 45, no. 4 (2019): 416–25. http://dx.doi.org/10.2341/19-089-l.

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Clinical Relevance Marginal misfit of monolithic lithium disilicate ceramic crowns obtained from a chairside computer-aided design/computer-aided manufacturing system is affected after successive millings using a single diamond bur set. This fact can be critical for the longevity of indirect restorations. SUMMARY Objectives: This laboratory study aimed to assess the effect of successive crown millings on the marginal misfit of monolithic full-ceramic restorations obtained from two lithium disilicate systems, with a single diamond bur set used for each material in a chairside computer-aided design/computer-aided manufacturing (CAD/CAM) unit. Methods and Materials: Initially, 36 standardized composite resin dies were produced by additive manufacturing from a three-dimensional model of a right mandibular first molar with full-crown preparation generated in CAD software. Individual ceramic crowns were obtained in a chairside CAD/CAM unit (CEREC MC XL) for each composite resin die according to the ceramic system (IPS e.max CAD and Rosetta SM; n=18). Two new diamond burs were used as a set for obtaining the crowns in each experimental group (ceramic systems), and the milling periods were defined after three crown millings (T0-T6), when the diamond bur set of each system was removed for morphologic characterization using scanning electron microscopy (SEM). The marginal misfit of the crowns was assessed through coronal and sagittal micro-tomographic sectioning, in the vertical and horizontal directions of the ceramic crowns seated on their respective resin dies. The collected data were tabulated and subjected to one-way analysis of variance and Tukey's honestly significant difference test (α=0.05). Results: SEM images showed changes in the superficial morphology of the diamond bur sets, with progressive loss of the diamond granules after the successive millings of crowns for both experimental groups. Significant differences were detected in the marginal misfit of the crowns from both ceramic systems at the different milling periods (p&lt;0.001). Conclusions: Diamond burs deteriorated after successive crown millings for both lithium disilicate ceramic systems. The marginal misfit of the crowns obtained increased with the successive use of the CAD/CAM diamond bur set employed for milling each ceramic material. In addition, new milling of full lithium disilicate ceramic crowns can be inappropriate after 11 successive millings for IPS e.max CAD and 12 for Rosetta SM, due to the increased marginal misfit observed under the parameters tested.

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Kazemi, Alireza, Karl D. Stephen, and Asghar Shams. "Seismic History Matching of Nelson Using Time-Lapse Seismic Data: An Investigation of 4D Signature Normalization." SPE Reservoir Evaluation & Engineering 14, no. 05 (2011): 621–33. http://dx.doi.org/10.2118/131538-pa.

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Summary History matching of a reservoir model is always a difficult task. In some fields, we can use time-lapse (4D) seismic data to detect production-induced changes as a complement to more conventional production data. In seismic history matching, we predict these data and compare to observations. Observed time-lapse data often consist of relative measures of change, which require normalization. We investigate different normalization approaches, based on predicted 4D data, and assess their impact on history matching. We apply the approach to the Nelson field in which four surveys are available over 9 years of production. We normalize the 4D signature in a number of ways. First, we use predictions of 4D signature from vertical wells that match production, and we derive a normalization function. As an alternative, we use crossplots of the full-field prediction against observation. Normalized observations are used in an automatic-history-matching process, in which the model is updated. We analyze the results of the two normalization approaches and compare against the case of just using production data. The result shows that when we use 4D data normalized to wells, we obtain 49% reduced misfit along with 36% improvement in predictions. Also over the whole reservoir, 8 and 7% reduction of misfits for 4D seismic are obtained in history and prediction periods, respectively. When we use only production data, the production history match is improved to a similar degree (45%), but in predictions, the improvement is only 25% and the 4D seismic misfit is 10% worse. Finding the unswept areas in the reservoir is always a challenge in reservoir management. By using 4D data in history matching, we can better predict reservoir behavior and identify regions of remaining oil.

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Gao, Fuchun, Alan R. Levander, R. Gerhard Pratt, Colin A. Zelt, and Gian Luigi Fradelizio. "Waveform tomography at a groundwater contamination site: VSP-surface data set." GEOPHYSICS 71, no. 1 (2006): H1—H11. http://dx.doi.org/10.1190/1.2159049.

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Application of 2D frequency-domain waveform tomography to a data set from a high-resolution vertical seismic profiling (VSP) experiment at a groundwater contamination site in Hill Air Force Base (HAFB), Utah, reveals a surprisingly complicated shallow substructure with a resolution of approximately 1.5 m. Variance in the waveform misfit function is reduced 69.4% by using an initial velocity model from first-arrival traveltime tomography. The waveform tomography model suggests (1) a low-velocity layer at 1 to 4 m depth, (2) a high-vertical-velocity gradient of 80 m/s/m on average, and (3) severe lateral variations — velocity contrasts as large as about 200 m/s occur in a distance as short as 1.5 m. The model is well correlated with lithologic logs and is interpreted geologically. A Q-value of 20 is estimated for the target area. The extreme lateral and vertical variations of the subsurface compromise many standard seismic processing methods.

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Ruschel, George Hebert, Ataís Bacchi, Izabela Cristina Maurício Moris, Stephanie Francoi Poole, Ricardo Faria Ribeiro, and Érica Alves Gomes. "Internal and Marginal Fit and Fracture Strength of Narrow Diameter Dental Implant-Abutment Assembly." Brazilian Dental Journal 31, no. 2 (2020): 127–34. http://dx.doi.org/10.1590/0103-6440202002937.

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Abstract The aim of this study was to assess the internal and vertical marginal fit of metallic copings to abutments and the fracture strength of different narrow diameter dental implant/abutments, either submitted to thermomechanical cycling or not. Sixty-four implant/abutments (n=16) were divided into 4 groups according to diameter and abutment type: G3.5-UAC (morse taper implant Ø3.5mm + universal abutment with beveled chamfer finish); G2.9-UAS (morse taper implant Ø2.9mm + universal abutment with shoulder finish); G2.8-AA (morse taper friction implant Ø2.8mm + anatomical abutment) and G2.5-HP (one-piece implant Ø2.5mm with indexed hexagonal platform). Each group was divided into two subgroups (n=8): submitted and not submitted to thermomechanical cycling (TMC). To assess internal and vertical marginal fit of metallic copings, the assemblies were scanned using microtomography (micro-CT) (n=5). The samples were subjected to the compressive strength test on a universal test machine. Group G3.5-UAC showed the highest marginal misfit regardless of TMC (p<0.05). All other groups were similar after TMC. Group G2.8-AA showed the lowest internal misfit both with and without TMC (p<0.05). Group G2.8-AA showed the highest fracture strength, similar only to G2.5-HP without TMC and G3.5-UAC with TMC. The type of abutment affects the internal and marginal fit of metallic copings and the anatomical abutment led to the best internal and marginal coping fit. The narrow diameter dental implant/abutments differ in terms of fracture strength, the strongest assembly was that composed by implant of type V grade titanium without internal threads (friction implant).

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Kim, Hyung Seok, Ju Hyung Suh, Chan Gyung Park, et al. "Microstructures and Growth Characteristics of Self-Assembled InAs/GaAs Quantum Dots Investigated by Transmission Electron Microscopy." Advanced Materials Research 26-28 (October 2007): 1207–10. http://dx.doi.org/10.4028/www.scientific.net/amr.26-28.1207.

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The microstructure and strain characteristics of self-assembled InAs/GaAs quantum dots (QDs) were studied by using transmission electron microscopy. Compressive strain was induced to uncapped QDs from GaAs substrate and the misfit strain largely increased after the deposition of GaAs cap layer. Tensile strain outside QD was extended along the vertical growth direction; up to 15 nm above the wetting layer. Vertically nonaligned and aligned stacked QDs were grown by adjusting the thickness of GaAs spacer layers. The QDs with a lens-shaped morphology were formed in the early stage of growth, and their apex was flattened by the out-diffusion of In atoms upon GaAs capping. However, aligned QDs maintained their lens-shaped structure with round apex after capping. It is believed that their apex did not flatten because the chemical potential gradient of In was relatively low due to the adjacent InAs QD layers.

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Toverud, Tommy, and Bjørn Ursin. "Comparison of seismic attenuation models using zero-offset vertical seismic profiling (VSP) data." GEOPHYSICS 70, no. 2 (2005): F17—F25. http://dx.doi.org/10.1190/1.1884827.

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For seismic frequencies it is common to use an empirical equation to model attenuation. Usually the attenuation coefficient is modeled with linear frequency dependence, a model referred to as the Kolsky-Futterman model. Other models have been suggested in the geophysical literature. We compare eight of these models on a zero-offset vertical seismic profiling (VSP) data set: the Kolsky-Futterman, the power law, the Kjartansson, the Müller, the Azimi second, the Azimi third, the Cole-Cole, and the standard linear solid (SLS) models. For three separate depth zones we estimate velocities and Q-values for all eight models. A least-squares model-fitting algorithm gives almost the same normalized misfit for all models. Thus, none of the models can be preferred or rejected based on the given data set. Slightly better overall results are obtained for the Kolsky-Futterman model; for one depth zone, the SLS model gave the best result.

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Rodríguez-Pérez, Quetzalcoatl, F. Ramón Zúñiga, Víctor H. Márquez-Ramírez, and Fernando Corbo-Camargo. "Seismoelectromagnetic effects associated with the 2017 February 15 Veracruz earthquake (Mw = 4.8)." Geophysical Journal International 222, no. 2 (2020): 1405–22. http://dx.doi.org/10.1093/gji/ggaa247.

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SUMMARY In this study, we investigated correlations between electromagnetic and seismic signals of the 2017 February 15 Veracruz, Mexico, earthquake (Mw = 4.8). We carried out a time–frequency misfit analysis based on the continuous wavelet transform in order to compare electric, magnetic and seismic records accurately. This analysis was performed for horizontal and vertical components separately. Our results from time–frequency misfit and goodness-of-fit criteria confirm the general similarity between seismic and electromagnetic signals both in frequency and time. Additionally, we studied the behaviour of peak amplitudes of seismoelectromagenetic records as a function of magnitude and distance. Our observations are in good agreement with previous studies, confirming scaling with magnitude and attenuation with distance. Radiated seismic energy estimations were performed with two methods: integration of velocity records and empirical Green function, respectively. Estimated energy magnitudes (4.35 &lt; Me &lt; 4.98) are consistent with reported seismic magnitudes for this event. We propose a method for determining electric and magnetic coseismic energies based on the concept of energy flux as implemented in the frequency domain by the integration of electromagnetic records. The calculated energies showed that the radiated seismic energy is much higher than the electric and magnetic energies.

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Junior, Wilson M., Cleuber R. de S. Bueno, José R. de AC Filho, et al. "Analysis of Vertical Misfit of Crowns Fabricated with CAD/CAM Technology using Two Scanning Techniques: Direct and Indirect." Journal of Contemporary Dental Practice 20, no. 3 (2019): 285–90. http://dx.doi.org/10.5005/jp-journals-10024-2511.

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Neukirch, Maik, Antonio García-Jerez, Antonio Villaseñor, Francisco Luzón, Mario Ruiz, and Luis Molina. "Horizontal-to-Vertical Spectral Ratio of Ambient Vibration Obtained with Hilbert–Huang Transform." Sensors 21, no. 9 (2021): 3292. http://dx.doi.org/10.3390/s21093292.

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The Horizontal-to-Vertical Spectral Ratio (HVSR) of ambient vibration measurements is a common tool to explore near surface shear wave velocity (Vs) structure. HVSR is often applied for earthquake risk assessments and civil engineering projects. Ambient vibration signal originates from the combination of a multitude of natural and man-made sources. Ambient vibration sources can be any ground motion inducing phenomena, e.g., ocean waves, wind, industrial activity or road traffic, where each source does not need to be strictly stationary even during short times. Typically, the Fast Fourier Transform (FFT) is applied to obtain spectral information from the measured time series in order to estimate the HVSR, even though possible non-stationarity may bias the spectra and HVSR estimates. This problem can be alleviated by employing the Hilbert–Huang Transform (HHT) instead of FFT. Comparing 1D inversion results for FFT and HHT-based HVSR estimates from data measured at a well studied, urban, permanent station, we find that HHT-based inversion models may yield a lower data misfit χ2 by up to a factor of 25, a more appropriate Vs model according to available well-log lithology, and higher confidence in the achieved model.

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Rangelova, E., W. Van Der Wal, and M. G. Sideris. "How Significant is the Dynamic Component of the North American Vertical Datum?" Journal of Geodetic Science 2, no. 4 (2012): 281–89. http://dx.doi.org/10.2478/v10156-012-0005-7.

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AbstractOne of the main current geodetic activities in North America is the definition and establishment of a geoid-based vertical datum that will replace the official CGVD28 and NAVD88 datums in Canada and the USA, respectively. The new datum will also have a time-dependent (dynamic) component required by the targeted one-centimetre accuracy of the datum. Heights of the levelling benchmarks are subject to temporal changes, which contribute to the degradation of the accuracy of the datum and increase the misfit of the geoid heights determined gravimetrically and by GNSS/levelling. The zero level surface, i.e., the geoid, also changes with time, most significantly due to postglacial rebound, climate-induced loss of polar ice masses and mountain glaciers, and hydrology variations. In this study, we examine the possible changes of the datum due to the aforementioned factors. We are mostly concerned with postglacial rebound as it can contribute more than 1 mm per year and more than 1 cm per decade to the geoid change. We also assess the significance of the temporal geoid and benchmark height changes and show that, compared to its current accuracy, the geoid change is only significant after a decade mostly in the flat areas of central Canada.

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Yang, Jidong, Hejun Zhu, George McMechan, Houzhu Zhang, and Yang Zhao. "Elastic least-squares reverse time migration in vertical transverse isotropic media." GEOPHYSICS 84, no. 6 (2019): S539—S553. http://dx.doi.org/10.1190/geo2018-0887.1.

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Using adjoint-based elastic reverse time migration, it is difficult to produce high-quality reflectivity images due to the limited acquisition apertures, band-limited source time function, and irregular subsurface illumination. Through iteratively computing the Hessian inverse, least-squares migration enables us to reduce the point-spread-function effects and improve the image resolution and amplitude fidelity. By incorporating anisotropy in the 2D elastic wave equation, we have developed an elastic least-squares reverse time migration (LSRTM) method for multicomponent data from the vertically transversely isotropic (VTI) media. Using the perturbed stiffness parameters [Formula: see text] and [Formula: see text] as PP and PS reflectivities, we linearize the elastic VTI wave equation and obtain a Born modeling (demigration) operator. Then, we use the Lagrange multiplier method to derive the corresponding adjoint wave equation and reflectivity kernels. With linearized forward modeling and adjoint migration operators, we solve a linear inverse problem to estimate the subsurface reflectivity models for [Formula: see text] and [Formula: see text]. To reduce the artifacts caused by data over-fitting, we introduce total-variation regularization into the reflectivity inversion, which promotes a sparse solution in terms of the model derivatives. To accelerate the convergence of LSRTM, we use source illumination to approximate the diagonal Hessian and use it as a preconditioner for the misfit gradient. Numerical examples help us determine that our elastic VTI LSRTM method can improve the spatial resolution and amplitude fidelity in comparison to adjoint migration.

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Grigoriev, D., S. Lazarev, P. Schroth, et al. "Asymmetric skew X-ray diffraction at fixed incidence angle: application to semiconductor nano-objects." Journal of Applied Crystallography 49, no. 3 (2016): 961–67. http://dx.doi.org/10.1107/s1600576716006385.

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A procedure for obtaining three-dimensionally resolved reciprocal-space maps in a skew X-ray diffraction geometry is described. The geometry allows tuning of the information depth in the range from tens of micrometres for symmetric skew diffraction down to tens of nanometres for strongly asymmetric skew geometries, where the angle of incidence is below the critical angle of total external reflection. The diffraction data are processed using a rotation matrix formalism. The whole three-dimensional reciprocal-space map can be measured by performing a single azimuthal rotation of the sample and using a two-dimensional detector, while keeping the angle of incidence and the X-ray information depth fixed (FIXD method). Having a high surface sensitivity under grazing-incidence conditions, the FIXD method can be applied to a large variety of Bragg reflections, particularly polar ones, which provide information on strain and chemical composition separately. In contrast with conventional grazing-incidence diffraction, the FIXD approach reveals, in addition to the lateral (in-plane) components, the vertical (out-of-plane) component of the strain field, and therefore allows the separation of the scattering contributions of strained epitaxial nanostructures by their vertical misfit. The potential of FIXD is demonstrated by resolving the diffraction signal from a single layer of InGaN quantum dots grown on a GaN buffer layer. The FIXD approach is suited to the study of free-standing and covered near-surface nano-objects, as well as vertically extended multilayer structures.

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Marzegalli, Anna, Fabio Isa, Heiko Groiss, et al. "Unexpected Dominance of Vertical Dislocations in High-Misfit Ge/Si(001) Films and Their Elimination by Deep Substrate Patterning." Advanced Materials 25, no. 32 (2013): 4408–12. http://dx.doi.org/10.1002/adma.201300550.

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Tobar, Celia, Verónica Rodríguez, Carlos Lopez-Suarez, Jesús Peláez, Jorge Cortés-Bretón Brinckmann, and María J. Suárez. "Effect of Digital Technologies on the Marginal Accuracy of Conventional and Cantilever Co–Cr Posterior-Fixed Partial Dentures Frameworks." Applied Sciences 11, no. 7 (2021): 2988. http://dx.doi.org/10.3390/app11072988.

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The introduction of new digital technologies represents an important advance to fabricate metal–ceramic restorations. However, few studies have evaluated the influence of these technologies on the fit of the restorations. The aim of this study was to evaluate the effect of different manufacturing techniques and pontic design on the vertical marginal fit of cobalt–-chromium (Co–Cr) posterior fixed partial dentures (FPDs) frameworks. Methods: Eighty stainless-steel dies were prepared to receive 3-unit FPDs frameworks with intermediate pontic (n = 40) and cantilever pontic (n = 40). Within each design, the specimens were randomly divided into four groups (n = 10 each) depending on the manufacturing technique: casting (CM), direct metal laser sintering (LS), soft metal milling (SM), and hard metal milling (HM). The frameworks were luted, and the vertical marginal discrepancy was assessed. Data analysis was made using Kruskal–Wallis and Mann–Whitney U tests (α = 0.05). Results: The vertical marginal discrepancy values of all FPDs were below 50 μm. The HM frameworks obtained the lowest misfit values in both designs. However, no differences were found among intermediate pontic groups or cantilevered groups. Likewise, when differences in a marginal discrepancy between both framework designs were analyzed, no differences were observed. Conclusions: The analyzed digital technologies demonstrated high precision of fit on Co–Cr frameworks and on both pontic designs.

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Yang, B., and E. Pan. "Elastic Fields of Quantum Dots in Multilayered Semiconductors: A Novel Green’s Function Approach." Journal of Applied Mechanics 70, no. 2 (2003): 161–68. http://dx.doi.org/10.1115/1.1544540.

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We present an efficient and accurate continuum-mechanics approach to predict the elastic fields in multilayered semiconductors due to buried quantum dots (QDs). Our approach is based on a novel Green’s function solution in anisotropic and linearly elastic multilayers, derived within the framework of generalized Stroh formalism and Fourier transforms, in conjunction with the Betti’s reciprocal theorem. By using this approach, the induced elastic fields due to QDs with general misfit strains are expressed as a volume integral over the QDs domains. For QDs with uniform misfit strains, the volume integral involved is reduced to a surface integral over the QDs boundaries. Further, for QDs that can be modeled as point sources, the induced elastic fields are then derived as a sum of the point-force Green’s functions. In the last case, the solution of the QD-induced elastic field is analytical, involving no numerical integration, except for the evaluation of the Green’s functions. As numerical examples, we have studied a multilayered semiconductor system of QDs made of alternating GaAs-spacer and InAs-wetting layers on a GaAs substrate, plus a freshly deposited InAs-wetting layer on the top. The effects of vertical and horizontal arrays of QDs and of thickness of the top wetting layer on the QD-induced elastic fields are examined and some new features are observed that may be of interest to the designers of semiconductor QD superlattices.

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Gibson, Richard L., Vincent Durussel, and Kyoung-Jin Lee. "Modeling and velocity analysis with a wavefront-construction algorithm for anisotropic media." GEOPHYSICS 70, no. 4 (2005): T63—T74. http://dx.doi.org/10.1190/1.1988188.

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Wavefront construction methods allow for efficient simulation of seismic wave propagation in anisotropic media using ray theory. This approach models an individual wavefront as a mesh that is adaptively refined as the wave travels through an earth model. The algorithm, implemented here for quasi-compressional waves, provides an effective tool for modeling and analyzing a large vertical seismic-profile data set from the Gulf of Mexico. Seismic velocities in this region generally increase linearly with depth, but simulations show that an isotropic vertical-gradient model cannot accurately reproduce traveltimes of first arrivals. However, a simple velocity-analysis inversion based on the wavefront-construction method allows a straightforward estimation of improved isotropic and transversely isotropic models that significantly reduce the misfit between computed traveltimes and the observations. The goal of this analysis is to produce a simple model suitable for use as a starting point for migrations and for assessing the importance of anisotropy in the field site. In fact, the final anisotropic model is much more consistent with background geologic information than the best isotropic model, which also has a larger rms traveltime error. The results strongly support the presence of measurable anisotropy.

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Mehta, M., G. Balakrishnan, S. Huang, et al. "GaSb quantum-well-based “buffer-free” vertical light emitting diode monolithically embedded within a GaAs cavity incorporating interfacial misfit arrays." Applied Physics Letters 89, no. 21 (2006): 211110. http://dx.doi.org/10.1063/1.2396897.

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Wu, Huaping, Guozhong Chai, Ting Zhou, Zheng Zhang, Takayuki Kitamura, and Haomiao Zhou. "Adjustable magnetoelectric effect of self-assembled vertical multiferroic nanocomposite films by the in-plane misfit strain and ferromagnetic volume fraction." Journal of Applied Physics 115, no. 11 (2014): 114105. http://dx.doi.org/10.1063/1.4868896.

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Adolfi, Dario, João Tribst, Alexandre Borges, and Marco Bottino. "Torque Maintenance Capacity, Vertical Misfit, Load to Failure, and Stress Concentration of Zirconia Restorations Cemented or Notched to Titanium Bases." International Journal of Oral & Maxillofacial Implants 35, no. 2 (2020): 357–65. http://dx.doi.org/10.11607/jomi.7731.

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Wu, Huaping, Guozhong Chai, Bin Xu, Jiquan Li, and Zheng Zhang. "Effect of out-of-plane misfit strain on phase diagrams and ferroelectric properties of ferroelectric films in vertical nanocomposite structures." Applied Physics A 113, no. 1 (2013): 155–60. http://dx.doi.org/10.1007/s00339-012-7503-4.

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Pan, Guangdong, Lin Liang, and Tarek M. Habashy. "A numerical study of 3D frequency-domain elastic full-waveform inversion." GEOPHYSICS 84, no. 1 (2019): R99—R108. http://dx.doi.org/10.1190/geo2017-0727.1.

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We have developed a 3D elastic full-waveform inversion (FWI) algorithm with forward modeling and inversion performed in the frequency domain. The Helmholtz equation is solved with a second-order finite-difference method using an iterative solver equipped with an efficient complex-shifted incomplete LU-based preconditioner. The inversion is based on the minimization of the data misfit functional and a total variation regularization for the unknown model parameters. We implement the Gauss-Newton method as the optimization engine for the inversions. The codes are parallelized with a message passing interface based on the number of shots and receivers. We examine the performance of this elastic FWI algorithm and workflow on synthetic examples including surface seismic and vertical seismic profile configurations. With various initial models, we manage to obtain high-quality velocity images for 3D earth models.

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Journal articles on the topic 'Vertical misfit'

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