A New Generation Low Frequency Vibrator for the Next Generation of Seismic Imaging and FWI

2020 ◽  
Author(s):  
Z. Wei ◽  
J. Criss
Keyword(s):  
Seismic Imaging ◽  
Low Frequency ◽  
Next Generation ◽  
New Generation

Does histological assessment accurately distinguish separate primary lung adenocarcinomas from intrapulmonary metastases? A study of paired resected lung nodules in 32 patients using a routine next-generation sequencing panel for driver mutations

2021 ◽  
pp. jclinpath-2021-207421
Author(s):  
Frido K Bruehl ◽  
Erika E Doxtader ◽  
Yu-Wei Cheng ◽  
Daniel H Farkas ◽  
Carol Farver ◽  
...  
Keyword(s):  
Next Generation Sequencing ◽  
Molecular Analysis ◽  
Low Frequency ◽  
Driver Mutations ◽  
Lung Nodules ◽  
Driver Gene ◽  
Next Generation ◽  
Histological Assessment ◽  
Lung Adenocarcinomas ◽  
Generation Sequencing

AimVarious approaches have been reported for distinguishing separate primary lung adenocarcinomas from intrapulmonary metastases in patients with two lung nodules. The aim of this study was to determine whether histological assessment is reliable and accurate in distinguishing separate primary lung adenocarcinomas from intrapulmonary metastases using routine molecular findings as an adjunct.MethodsWe studied resected tumour pairs from 32 patients with lung adenocarcinomas in different lobes. In 15 of 32 tumour pairs, next-generation sequencing (NGS) for common driver mutations was performed on both nodules. The remainder of tumour pairs underwent limited NGS, or EGFR genotyping. Tumour pairs with different drivers (or one driver/one wild-type) were classified as molecularly unrelated, while those with identical low-frequency drivers were classified as related. Three pathologists independently and blinded to the molecular results categorised tumour pairs as related or unrelated based on histological assessment.ResultsOf 32 pairs, 15 were classified as related by histological assessment, and 17 as unrelated. Of 15 classified as related by histology, 6 were classified as related by molecular analysis, 4 were unrelated and 5 were indeterminate. Of 17 classified as unrelated by histology, 14 were classified as unrelated by molecular analysis, none was related and 3 were indeterminate. Histological assessment of relatedness was inaccurate in 4/32 (12.5%) tumour pairs.ConclusionsA small but significant subset of two-nodule adenocarcinoma pairs is inaccurately judged as related by histological assessment, and can be proven to be unrelated by molecular analysis (driver gene mutations), leading to significant downstaging.

scholarly journals Detection of genome-wide low-frequency mutations with Paired-End and Complementary Consensus Sequencing (PECC-Seq) revealed end-repair derived artifacts as residual errors

2019 ◽  
Author(s):  
Xinyue You ◽  
Suresh Thiruppathi ◽  
Weiying Liu ◽  
Yiyi Cao ◽  
Mikihiko Naito ◽  
...  
Keyword(s):  
Next Generation Sequencing ◽  
Low Frequency ◽  
Repair Process ◽  
Sequencing Error ◽  
Base Substitution ◽  
Next Generation ◽  
Background Error ◽  
Technical Errors ◽  
Genome Wide ◽  
Generation Sequencing

ABSTRACTTo improve the accuracy and the cost-efficiency of next-generation sequencing in ultralow-frequency mutation detection, we developed the Paired-End and Complementary Consensus Sequencing (PECC-Seq), a PCR-free duplex consensus sequencing approach. PECC-Seq employed shear points as endogenous barcodes to identify consensus sequences from the overlap in the shortened, complementary DNA strands-derived paired-end reads for sequencing error correction. With the high accuracy of PECC-Seq, we identified the characteristic base substitution errors introduced by the end-repair process of mechanical fragmentation-based library preparations, which were prominent at the terminal 6 bp of the library fragments in the 5’-NpCpA-3’ or 5’-NpCpT-3’ trinucleotide context. As demonstrated at the human genome scale (TK6 cells), after removing these potential end-repair artifacts from the terminal 6 bp, PECC-Seq could reduce the sequencing error frequency to mid-10−7 with a relatively low sequencing depth. For TA base pairs, the background error rate could be suppressed to mid-10−8. In mutagen-treated TK6, slight increases in mutagen treatment-related mutant frequencies could be detected, indicating the potential of PECC-Seq in detecting genome-wide ultra-rare mutations. In addition, our finding on the patterns of end-repair artifacts may provide new insights in further reducing technical errors not only for PECC-Seq, but also for other next-generation sequencing techniques.

The Next Generation of Internet Portals

2011 ◽  
pp. 89-100
Author(s):  
Ali Jafari
Keyword(s):  
Artificial Intelligence ◽  
World Wide Web ◽  
World Wide ◽  
Next Generation ◽  
The World ◽  
Internet Portals ◽  
New Generation

Today’s portals bring together existing technologies in useful, innovative ways, but they don’t scratch the surface of what is possible. The constant build-up of information and resources on the World Wide Web demands a smarter more advanced portal technology that offers dynamic, personalized, customized, and intelligent services. This chapter discusses next-generation portals and the requirement that they come to know their users and understand their individual interests and preferences. It describes a new generation of portals that have a level of autonomy, making informed, logical decisions and performing useful tasks on behalf of their members. The chapter highlights the role of artificial intelligence in framing the next generation of portal technology and in developing their capabilities for learning about their users.

Assessing uncertainties in velocity models and images with a fast nonlinear uncertainty quantification method

Geophysics ◽  
2018 ◽  
Vol 83 (2) ◽  
pp. R63-R75 ◽  
Author(s):  
Gregory Ely ◽  
Alison Malcolm ◽  
Oleg V. Poliannikov
Keyword(s):  
Uncertainty Quantification ◽  
Seismic Imaging ◽  
Low Frequency ◽  
Expansion Method ◽  
Velocity Model ◽  
Image Features ◽  
Visible Image ◽  
Waveform Data ◽  
Velocity Models ◽  
Seismic Reflections

Seismic imaging is conventionally performed using noisy data and a presumably inexact velocity model. Uncertainties in the input parameters propagate directly into the final image and therefore into any quantity of interest, or qualitative interpretation, obtained from the image. We considered the problem of uncertainty quantification in velocity building and seismic imaging using Bayesian inference. Using a reduced velocity model, a fast field expansion method for simulating recorded wavefields, and the adaptive Metropolis-Hastings algorithm, we efficiently quantify velocity model uncertainty by generating multiple models consistent with low-frequency full-waveform data. A second application of Bayesian inversion to any seismic reflections present in the recorded data reconstructs the corresponding structures’ position along with its associated uncertainty. Our analysis complements rather than replaces traditional imaging because it allows us to assess the reliability of visible image features and to take that into account in subsequent interpretations.

Next Generation Turboprop Gearboxes

1982 ◽  
Author(s):  
W. L. McIntire ◽  
D. A. Wagner
Keyword(s):  
Operating Cost ◽  
Past Experience ◽  
Reduction Ratio ◽  
Next Generation ◽  
Propulsion Systems ◽  
Aircraft Systems ◽  
General Arrangement ◽  
Significant Interest ◽  
Direct Operating Cost ◽  
New Generation

A new generation of fuel-efficient turboprop propulsion systems is under consideration now that fuel is a significant portion of the direct operating cost of aircraft. Systems in the 5000- to 15,000-hp (3730- to 11,185-kW) range that use conventional propellers or the new propfan are being studied. Reduction gearing for this next generation of turboprops is of significant interest due to new requirements for cruise speed life, and reliability. Detroit Diesel Allison’s past experience with the T56 family of turboprop reduction gearboxes is recounted. Probable requirements of the next generation of reduction gearboxes are discussed since new requirements for gearboxes combined with past experience should determine the profile of the next generation of gearboxes. A discussion of gearbox general arrangement and its impact on airframe installation is included, along with comments on reduction ratio, gear arrangement, accessory drives, reliability goals, and probable technology needs.

scholarly journals Galactic neutral hydrogen and the magnetic ISM foreground

2017 ◽  
Vol 12 (S333) ◽  
pp. 146-150
Author(s):  
S.E. Clark
Keyword(s):  
Interstellar Medium ◽  
Dynamic Range ◽  
Low Frequency ◽  
Neutral Hydrogen ◽  
Depth Resolution ◽  
High Dynamic Range ◽  
Neutral Gas ◽  
High Dynamic ◽  
New Generation ◽  
The Relationship

AbstractThe interstellar medium is suffused with magnetic fields, which inform the shape of structures in the diffuse gas. Recent high-dynamic range observations of Galactic neutral hydrogen, combined with novel data analysis techniques, have revealed a deep link between the morphology of neutral gas and the ambient magnetic field. At the same time, an observational revolution is underway in low-frequency radio polarimetry, driven in part by the need to characterize foregrounds to the cosmological 21-cm signal. A new generation of experiments, capable of high angular and Faraday depth resolution, are revealing complex filamentary structures in diffuse polarization. The relationship between filamentary structures observed in radio-polarimetric data and those observed in atomic hydrogen is not yet well understood. Multiwavelength observations will enable new insights into the magnetic interstellar medium across phases.

PMPS: A Prototype CAPP System for Parallel Machining

1996 ◽  
Vol 118 (3) ◽  
pp. 406-414 ◽  
Author(s):  
J. B. Levin ◽  
D. Dutta
Keyword(s):  
Process Planning ◽  
Machine Tools ◽  
Machining Accuracy ◽  
Next Generation ◽  
Computer Aided Process Planning ◽  
Cycle Times ◽  
The Past ◽  
Computer Aided ◽  
Machining Operations ◽  
New Generation

Parallel N.C. machines, also referred to as mill-turns, are a new generation of machine tools aimed at increasing machining accuracy and reducing part cycle times. In addition to their capacity to do both milling and turning, these next generation machines tools can perform multiple machining operations simultaneously, involving one or more parts at a time, and can completely finish a part (front and back) in a single setup. Parallel machining raises issues with respect to computer aided process planning which have not been dealt with in the past. In this paper, a prototype CAPP system called PMPS, for parallel machining, is described. First, we briefly highlight the new issues to be dealt with in process planning for parallel machining. Next, the architecture and details of PMPS, a generative CAPP system, is described. Finally, the implementation and results are discussed.

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