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1

Compressive sensing aided seismic geometry design for offshore acquisition

Huang Xiaogang, Zhang Jinmiao, Du Xiangdong, Zhu Zhenyu, Li Weixin, Zhang Yiming, Ding Jicai, Liu Zhipeng, Zhang Jianfeng

Acta Geophysica

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2022

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Vol. 70, no 2

547--562

EN

Seismic acquisition guided by the compressive sensing theory can significantly improve seismic data acquisition efficiency and reduce the cost. After reviewing the basic principles of compressive sensing, we propose an optimized random sampling method that can control the maximum sampling interval and improve the design flexibility. We analyze several factors that can introduce reconstruction errors from compressive sensed data and learn that besides sampling method, reconstruction errors increase with decimation degree and the complexity of structures and also depend on the reconstruction workflow. In addition, we provide a basic workflow of the geometry design of compressive sensing acquisition. We analyze the feasibility of the three types of receiving equipment that are widely used in marine environment and discuss the potential cost reduction and efficiency gain. Our field example demonstrates the detailed working process and the feasibility of the combination of random sailing line intervals and random shot intervals and verifies the effect of cost saving and efficiency increasing.

2

Triangle Sampling Path Planning in Environment with Danger Zones for Assembly/Disassembly

Peng F., Zhao Y.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 1b

167-172

EN

To plan a feasible path in the environment with danger zones for assembly/disassembly, a RRT-based path planning algorithm was presented. The algorithm addressed a new density avoided sampling function based on kurtosis coefficient for planning in the free configuration space, and introduced a random sampling function which obtains random state from the triangles that describe the danger zones. The local planner connecting the samples with RRT trees is also introduced. Experimental results show that the algorithm much more effectively searches the paths between danger zones and obstacles.

PL

Zaprezentowano metodę wyznaczania możliwej ścieżki ruchu w środowisku z zagrożeniami. Algorytm bazuje na systemie PRM (probabilistic roadmap) i RRT (rapidly-exploring random trees).

3

Ekonomiczny model badań niezawodnościowych goi

Yang S. F., Chien K. W-T

Eksploatacja i Niezawodność

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2010

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nr 2

79-82

EN

This paper studies the methods and guidelines in minimum sample size determination provided by JEDEC/ FSA joint publication and points out their drawbacks, inconsistency, and misguidance. We provide an exact method and easy-to-use numerical solution by extending JEDEC's formula to any allowed failure number, target defect density, and confi dence level. Important guidelines are also provided for reliability practitioners to reduce possible errors resulting from imperfect sampling procedures and to avoid mistakes in defect density evaluation against a target defect density (D0). Our proposed method can be applied to any reliability tests with the binomial distribution to determine a minimum sample size to save wafers and testing resources.

PL

Niniejsza praca analizuje metody i wytyczne dotyczące wyznaczania minimalnego rozmiaru próbki podane we wspólnej publikacji JEDEC/ FSA, wskazując na ich wady, niekonsekwencje i błędne wskazówki. W artykule podajemy dokładne i łatwe w użyciu rozwiązanie, które rozciąga wzór JEDEC na wszelką dozwoloną liczbę uszkodzeń, dopuszczalną gęstość defektów i poziom ufności. Przedstawiamy również ważne wytyczne dla specjalistów w zakresie niezawodności pozwalające zredukować możliwe błędy wynikające z niedoskonałych procedur próbkowania oraz uniknąć pomyłek w ocenie gęstości defektów względem dopuszczalnej gęstości defektów (D0). Proponowana przez nas metoda może być stosowana we wszelkich testach niezawodnościowych z rozkładem dwumianowym do wyznaczania minimalnego rozmiaru próbki przy oszczędnym użyciu płytek i środków badawczych.

4

Optimal random sampling for spectrum estimation in DASP applications

Tarczyński A., Qu D.

International Journal of Applied Mathematics and Computer Science

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2005

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Vol. 15, no 4

463-469

EN

In this paper we analyse a class of DASP (Digital Alias-free Signal Processing) methods for spectrum estimation of sampled signals. These methods consist in sampling the processed signals at randomly selected time instants. We construct estimators of Fourier transforms of the analysed signals. The estimators are unbiased inside arbitrarily wide frequency ranges, regardless of how sparsely the signal samples are collected. In order to facilitate quality assessment of the estimators, we calculate their standard deviations. The optimal sampling scheme that minimises the variance of the resulting estimator is derived. The further analysis presented in this paper shows how sampling instant jitter deteriorates the quality of spectrum estimation. A couple of numerical examples illustrate the main thesis of the paper