On: “Wavelets, well ties, and the search for subtle stratigraphic traps,” (A. Ziolkowski, J. R. Underhill, and R. G. K. Johnston, GEOPHYSICS, 63, 297–313)

Geophysics ◽  
1999 ◽  
Vol 64 (2) ◽  
pp. 636-640
Author(s):  
Roy E. White
Keyword(s):  
Quantitative Analysis ◽  
Seismic Data ◽  
State Of The Art ◽  
The State ◽  
Trade Offs

This paper by Ziolkowski, Underhill, and Johnson (abbreviated below to ZUJ) opens by speaking of problems in tying seismic data to wells that have not been addressed properly. Yet it fails to present any solid evidence of the problems it claims to address and shows no clear awareness of the state of the art. The paper’s arguments are sustained only by ignoring important distinctions, degrees of approximation, necessary trade‐offs in processing, and quantitative analysis.

scholarly journals Well-to-Seismic Tie of a Field Onshore of the Nigerian Delta

2021 ◽  
Vol 25 (1) ◽  
pp. 53-58
Author(s):  
S. Inichinbia ◽  
P.O. Saule
Keyword(s):  
Seismic Data ◽  
State Of The Art ◽  
The State ◽  
Spatial Extent ◽  
Strong Correlations ◽  
Rock Property ◽  
Well Location ◽  
Seismic Reflectors ◽  
Art Techniques

This work presents a modern procedure for understanding seismic data wavelets through well-toseismic tie on an onshore field in the Nigerian Delta using the state-of-the-art techniques. The purpose of this work is the correlation of formation tops and seismic  reflectors in the field. The objectives among others include the calibration of the seismic data in terms of polarity and phase, as well as to ensure that the seismic data is descriptive to well markers and discoveries, extending knowledge from the well location to rest of the field and reducing uncertainties. Logs from the two wells on the field and also logs from three wells on neighbouring fields were used to establish lateral continuity of the reservoirs H1000 and H4000. Their results show that the top, base and thickness of both reservoirs are quite variable laterally and this posed some challenges in the correlation from well to well. The field does not have checkshot data, so checkshot data from one of the wells on the neighbouring field was borrowed. Calibrated sonic and density logs of well01 and  well-02 were used to assess the seismic ties at the well locations. Strong correlations at the wells are fundamental to the evaluation of the spatial extent of the horizons around the wells from the seismic data. Seismic-to-well ties are a very important part of the interpreter’s business as they provide a means of correctly identifying horizons to pick, and estimating the wavelet for inverting seismic data to impedance and rock property indicators. Keywords: Seismic, horizons, correlation, synthetics

scholarly journals Variación fonética de /e/ y /r/ en el habla culta de San José

2015 ◽  
Vol 21 (1) ◽  
pp. 115
Author(s):  
Annette Calvo Shadid
Keyword(s):  
Quantitative Analysis ◽  
Costa Rica ◽  
Iberian Peninsula ◽  
Critical Review ◽  
First Generation ◽  
State Of The Art ◽  
Costa Rican ◽  
The State ◽  
San Jose ◽  
Costa Rican Spanish

Este artículo constituye una revisión crítica exhaustiva del estado de la técnica en la realización de los fonemas / r / y / r / en el español de Costa Rica . El artículo también describe la variación de estos fonemas sobre la base del análisis cuantitativo de una muestra, el habla de la primera generación educada de San José. La muestra forma parte de los datos recogidos para el Proyecto Coordinado sobre Variedad de Educación en las ciudades principales de Ibero América y la Península Ibérica.This article constitutes an exhaustive critical review of the state of the art on the realization of the phonemes / r / y / r / in Costa Rican Spanish. The article also describes variation of these phonemes on the basis of the quantitative analysis of a sample of female, first-generation educated speech from San José. The sample is part of the data gathered for the Coordinated Project on Educated Variety in the Main Cities of Ibero America and the Iberian Peninsula.

scholarly journals Blockchain Consensus: An Overview of Alternative Protocols

Symmetry ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1363
Author(s):  
Damilare Peter Oyinloye ◽  
Je Sen Teh ◽  
Norziana Jamil ◽  
Moatsum Alawida
Keyword(s):  
Energy Consumption ◽  
State Of The Art ◽  
Hash Functions ◽  
The State ◽  
Design Features ◽  
The Past ◽  
Trade Offs ◽  
Overall Performance ◽  
And Performance ◽  
Made In

Blockchain networks are based on cryptographic notions that include asymmetric-key encryption, hash functions and consensus protocols. Despite their popularity, mainstream protocols, such as Proof of Work or Proof of Stake still have drawbacks. Efforts to enhance these protocols led to the birth of alternative consensus protocols, catering to specific areas, such as medicine or transportation. These protocols remain relatively unknown despite having unique merits worth investigating. Although past reviews have been published on popular blockchain consensus protocols, they do not include most of these lesser-known protocols. Highlighting these alternative consensus protocols contributes toward the advancement of the state of the art, as they have design features that may be useful to academics, blockchain practitioners and researchers. In this paper, we bridge this gap by providing an overview of alternative consensus protocols proposed within the past 3 years. We evaluate their overall performance based on metrics such as throughput, scalability, security, energy consumption, and finality. In our review, we examine the trade-offs that these consensus protocols have made in their attempts to optimize scalability and performance. To the best of our knowledge, this is the first paper that focuses on these alternative protocols, highlighting their unique features that can be used to develop future consensus protocols.

scholarly journals Invariance from the Euclidean Geometer's Perspective

Perception ◽  
1994 ◽  
Vol 23 (5) ◽  
pp. 547-561 ◽  
Author(s):  
Luc J Van Gool ◽  
Theo Moons ◽  
Eric Pauwels ◽  
Johan Wagemans
Keyword(s):  
Object Recognition ◽  
Machine Vision ◽  
Visual System ◽  
Human Visual System ◽  
State Of The Art ◽  
The State ◽  
The Other ◽  
Other Hand ◽  
Trade Offs ◽  
Basic Philosophy

It is remarkable how well the human visual system can cope with changing viewpoints when it comes to recognising shapes. The state of the art in machine vision is still quite remote from solving such tasks. Nevertheless, a surge in invariance-based research has led to the development of methods for solving recognition problems still considered hard until recently. A nonmathematical account explains the basic philosophy and trade-offs underlying this strand of research. The principles are explained for the relatively simple case of planar-object recognition under arbitrary viewpoints. Well-known Euclidean concepts form the basis of invariance in this case. Introducing constraints in addition to that of planarity may further simplify the invariants. On the other hand, there are problems for which no invariants exist.

scholarly journals Towards Globally Optimized Masking: From Low Randomness to Low Noise Rate

2019 ◽  
pp. 162-198 ◽  
Author(s):  
Gaëtan Cassiers ◽  
François-Xavier Standaert
Keyword(s):  
Quantitative Analysis ◽  
State Of The Art ◽  
Low Noise ◽  
The State ◽  
Multiple Target ◽  
Multiplication Algorithm ◽  
Noise Rate ◽  
Improved Algorithm

We improve the state-of-the-art masking schemes in two important directions. First, we propose a new masked multiplication algorithm that satisfies a recently introduced notion called Probe-Isolating Non-Interference (PINI). It captures a sufficient requirement for designing masked implementations in a trivial way, by combining PINI multiplications and linear operations performed share by share. Our improved algorithm has the best reported randomness complexity for large security orders (while the previous PINI multiplication was best for small orders). Second, we analyze the security of most existing multiplication algorithms in the literature against so-called horizontal attacks, which aim to reduce the noise of the actual leakages measured by an adversary, by combining the information of multiple target intermediate values. For this purpose, we leave the (abstract) probing model and consider a specialization of the (more realistic) noisy leakage / random probing models. Our (still partially heuristic but quantitative) analysis allows confirming the improved security of an algorithm by Battistello et al. from CHES 2016 in this setting. We then use it to propose new improved algorithms, leading to better tradeoffs between randomness complexity and noise rate, and suggesting the possibility to design efficient masked multiplication algorithms with constant noise rate in F2.

Practical Picture Processing

1974 ◽  
Vol 32 ◽  
pp. 338-339
Author(s):  
T. A. Welton
Keyword(s):  
Radiation Damage ◽  
Coherence Length ◽  
Spatial Information ◽  
State Of The Art ◽  
Coherent Radiation ◽  
The State ◽  
Energy Spread ◽  
Electron Micrograph ◽  
Picture Processing ◽  
Molecular Skeleton

Various authors have emphasized the spatial information resident in an electron micrograph taken with adequately coherent radiation. In view of the completion of at least one such instrument, this opportunity is taken to summarize the state of the art of processing such micrographs. We use the usual symbols for the aberration coefficients, and supplement these with £ and 6 for the transverse coherence length and the fractional energy spread respectively. He also assume a weak, biologically interesting sample, with principal interest lying in the molecular skeleton remaining after obvious hydrogen loss and other radiation damage has occurred.

Hypothesis-Evidence Coordination: The State of the Art

2003 ◽  
Vol 48 (6) ◽  
pp. 826-829 ◽  
Author(s):  
Eric Amsel
Keyword(s):  
State Of The Art ◽  
The State

The State of the Art

1968 ◽  
Vol 13 (9) ◽  
pp. 479-480
Author(s):  
LEWIS PETRINOVICH
Keyword(s):  
State Of The Art ◽  
The State

Needs Assessment: The State of the Art

1984 ◽  
Vol 29 (5) ◽  
pp. 426-428
Author(s):  
Anthony R. D'Augelli
Keyword(s):  
Needs Assessment ◽  
State Of The Art ◽  
The State
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