scholarly journals Identification of the Oscillation Period of Chemical Reactors by Chaotic Sampling of the Conversion Degree

2014 ◽  
Vol 35 (3) ◽  
pp. 387-393 ◽  
Author(s):  
Marcin Lawnik ◽  
Marek Berezowski

Abstract To stabilise the periodic operation of a chemical reactor the oscillation period should be determined precisely in real time. The method discussed in the paper is based on adaptive sampling of the state variable with the use of chaotic mapping to itself. It enables precise determination of the oscillation period in real time and could be used for a proper control system, that can successfully control the process of chemical reaction and maintain the oscillation period at a set level. The method was applied to a tank reactor and tubular reactor with recycle.

2014 ◽  
Vol 19 (2) ◽  
pp. 172-177 ◽  
Author(s):  
Marek Berezowski ◽  
Marcin Lawnik

The adaptive approach of strongly non-linear fast-changing signals identification is discussed. The approach is devised by adaptive sampling based on chaotic mapping “in yourself” of a signal. Presented sampling way may be utilized online in the automatic control of chemical reactor (throughout identification of concentrations and temperature oscillations in real-time), in medicine (throughout identification of ECG and EEG signals in real-time), etc. In this paper, we presented it to identify the Weierstrass function and ECG signal.


1997 ◽  
Vol 51 (2) ◽  
pp. 247-252 ◽  
Author(s):  
Jeffrey F. Aust ◽  
Karl S. Booksh ◽  
Christopher M. Stellman ◽  
Richard S. Parnas ◽  
Michael L. Myrick

A method for real-time determination of the percent cure of epoxies via in situ fiber-optic Raman spectroscopy has been developed. This method utilizes a probe design developed for real-time monitoring of polymer curing and multivariate analysis to interpret the data and determine percent cure. This method was demonstrated to be reliable to ±0.54% of cure in laboratory samples over a 50–99% cure range. A preliminary study measuring cure percentage in an industrial, glass-reinforced composite has been shown to be reliable to ±0.82% in the 40–90% cure range.


Catalysts ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 37
Author(s):  
Marek Berezowski ◽  
Natalia Kozioł ◽  
Marcin Lawnik

Oscillations, including chaotic ones, can spontaneously appear in chemical reactors or lean premixed combustors. Such behavior of the system is undesirable and should be identified at the stage of its modeling. This article analyzes the behavior of reverse-flow tubular chemical reactor with longitudinal dispersion in terms of chaotic oscillations. The purpose of using reverse flow is to increase the conversion degree. For the analysis of the reactor, among others, spectral analysis, entropy, and bifurcation analysis were used. The obtained results show the chaotic behavior of the reactor in a wide range of changes in the parameter’s values.


INFO ARTHA ◽  
2017 ◽  
Vol 1 (1) ◽  
pp. 17-34
Author(s):  
Fadlil Usman

Probity audit is an independence assessment activity to ensure the goods/services procurement processes have been implemented consistently appropriate with the principle of upholding integrity, uprightness, honesty and fulfill certain occur legislation aimed for improving the accountability for the use of public sector fund. Probity audit is done in real time simultaneously with the goods/services procurement process. This study aims to evaluate the suitability of the implementation of probity audit conducted by BPKP Headquarter as agency that initiated the implementation of probity audit in Indonesia compared with the Probity audit Guidelines for Procurement of Goods/Services as criteria. The results of this study indicate that the implementation of probity audit conducted by BPKP Headquarter has been implemented adequately, but there are activities that do not fit the criteria, especially in the activities of the determination of the scope of the audit, the preparation of working papers and the follow-up monitoring of the audit results. Probity audit merupakan kegiatan penilaian (independen) untuk memastikan bahwa proses pengadaan barang/jasa telah dilaksanakan secara konsisten sesuai dengan prinsip penegakan integritas, kebenaran, kejujuran dan memenuhi ketentuan perundangan yang berlaku yang bertujuan meningkatkan akuntabilitas penggunaan dana sektor publik. Probity audit dilakukan secara real time yaitu bersamaan dengan pelaksanaan pengadaan barang/jasa. Penelitian ini bertujuan untuk melakukan evaluasi kesesuaian pelaksanaan probity audit yang dilakukan oleh BPKP Pusat selaku instansi yang menginisiasi pelaksanaan probity audit di Indonesia dibandingkan dengan kriteria berupa Pedoman Probity audit Pengadaan Barang/Jasa Pemerintah. Hasil dari penelitian ini menunjukkan bahwa pelaksanaan probity audit yang dilakukan oleh BPKP Pusat sudah dilaksanakan secara memadai, namun masih terdapat hal yang belum sesuai dengan kriteria terutama dalam kegiatan penentuan ruang lingkup audit, penyusunan kertas kerja dan pemantauan terhadap tindak lanjut hasil audit.


Sign in / Sign up

Export Citation Format

Share Document