Wyniki wyszukiwania - BazTech

1

Disassembly-free metrological control of analog-to-digital converter parameters

Bubela Tetiana, Kochan Roman, Więcław Łukasz, Yatsuk Vasyl, Kuts Victor, Yatsuk Jurij

Metrology and Measurement Systems

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2022

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Vol. 29, nr 4

669--684

EN

The authors update the issue disassembly-free control and correction of all components of the error of measuring channels with multi-bit analog-to-digital converters (ADCs). The main disadvantages of existing methods for automatic control of the parameters of multi-bit ADCs, in particular their nonlinearity, are identified. Methods for minimizing instrumental errors and errors caused by limited internal resistances of closed switches, input and output resistances of active elements are investigated. The structures of devices for determining the multiplicative and nonlinear components of the error of multi-bit ADCs based on resistive dividers built on single-nominal resistors are proposed and analyzed. The authors propose a method for the correction of additive, multiplicative and nonlinear components of the error at each of the specified points of the conversion range during non-disassembly control of the ADC with both types of inputs. The possibility of non-disassembly control, as well as correction of multiplicative and nonlinear components of the error of multi-bit ADCs in the entire range of conversion during their on-site control is proven. ADC error correction procedures are proposed. These procedures are practically invariant to the non-informative parameters of active structures with resistive dividers composed of single-nominal resistors. In the article the prospects of practical implementation of the method of error correction during non-dismantling control of ADC parameters using the possibilities provided by modern microelectronic components are shown. The ways to minimize errors are proposed and the requirements to the choice of element parameters for the implementation of the proposed technical solutions are given. It is proved that the proposed structure can be used for non-disassembly control of multiplicative and nonlinear components of the error of precision instrumentation amplifiers.

2

Oil Formation Volume Factor Determination Through a Fused Intelligence

Gholami A.

Acta Geophysica

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2016

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Vol. 64, no. 6

2510--2529

EN

Volume change of oil between reservoir condition and standard surface condition is called oil formation volume factor (FVF), which is very time, cost and labor intensive to determine. This study proposes an accurate, rapid and cost-effective approach for determining FVF from reservoir temperature, dissolved gas oil ratio, and specific gravity of both oil and dissolved gas. Firstly, structural risk minimization (SRM) principle of support vector regression (SVR) was employed to construct a robust model for estimating FVF from the aforementioned inputs. Subsequently, an alternating conditional expectation (ACE) was used for approximating optimal transformations of input/output data to a higher correlated data and consequently developing a sophisticated model between transformed data. Eventually, a committee machine with SVR and ACE was constructed through the use of hybrid genetic algorithm-pattern search (GA-PS). Committee machine integrates ACE and SVR models in an optimal linear combination such that makes benefit of both methods. A group of 342 data points was used for model development and a group of 219 data points was used for blind testing the constructed model. Results indicated that the committee machine performed better than individual models.

3

ACE - nowa metoda interpretacji cementomierzy akustycznych RBT

Faber B., Kobus L., Tomczak K.

Prace Naukowe Instytutu Nafty i Gazu

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2012

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nr 182 wyd. konferencyjne

361--366

PL

W opracowaniu omówiono nową metodę interpretacji cementomierzy akustycznych RBT z wykorzystaniem oprogramowania Advanced Cement Evaluation firmy Halliburton. Metoda ta pozwala na czytelne przedstawienie w formie graficznej: — objętościowej mapy stopnia związania kamienia cementowego; — przestrzennej mapy wypełnienia kamieniem cementowym przestrzeni pomiędzy rurami, lub rurą a ścianą otworu; — niedoskonałości procesu cementowania rur w otworze wiertniczym. Interpretację ACE możemy wykorzystać nie tylko przy ocenie stanu zacementowania rur w otworze wiertniczym, ale także do lokalizacji przychwyceń kolumny rur czy kontroli stanu obsypki w otworze geotermalnym.

EN

Advanced Cement Evaluation software of the Halliburton company is a new method of interpretation of cement bonding using the acoustic RBT tool. This method allows ~ show in simple graphical view: — volume cement bonding map, — spatial map of packing cement stone in space between pipes, or between pipe and wall of the hole, — imperfections of cementation process of pipes in the borehole. We can use ACE interpretation not only at the evaluation of the cementing pipes in the borehole, but also for the location of seizing the column of pipes, or control of gravel filter level in the geothermal well.

4

Approximate dynamic programming in robust tracking control of wheeled mobile robot

Hendzel Z., Szuster M.

Archive of Mechanical Engineering

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2009

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Vol. LVI, nr 3

223-236

EN

In this work, a novel approach to designing an on-line tracking controller for a nonholonomic wheeled mobile robot (WMR) is presented. The controller consists of nonlinear neural feedback compensator, PD control law and supervisory element, which assure stability of the system. Neural network for feedback compensation is learned through approximate dynamic programming (ADP). To obtain stability in the learning phase and robustness in face of disturbances, an additional control signal derived from Lyapunov stability theorem based on the variable structure systems theory is provided. Verification of the proposed control algorithm was realized on a wheeled mobile robot Pioneer-2DX, and confirmed the assumed behavior of the control system.

PL

W pracy przedstawiono nowe ujęcie problematyki sterowania nadążnego mobilnym robotem dwukołowym. Algorytm bazuje na metodzie uczenia ze wzmocnieniem o strukturze aktor-krytyk i nie wymaga uczenia wstępnego, działa on-line bez znajomości modelu robota. Element generujący sterowania (aktor - ASE) oraz element generujący sygnał wewnętrznego wzmocnienia (krytyk - ACE) są zrealizowane w postaci sztucznej sieci neuronowej (SN). Prezentowany algorytm sterowania zweryfikowano na rzeczywistym obiekcie, dwukołowym robocie mobilnym Pioneer-2DX. Badania potwierdziły poprawność przyjętego rozwiązania.