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Prediction of the static elastic modulus of limestone using downhole seismic test in Asmari formation

Daraei Ako, Sharifi Fereydoun, Qader Diyar Nasih, Hama Ali Hunar Farid, Kolivand Farshad

Acta Geophysica

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2024

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Vol. 72, no. 1

247--255

EN

Determining the elastic modulus of rocks is one of the crucial parameters in civil and petroleum engineering. Asmari geological formation is widely outcropped in a significant part of the west and SW of Iran and NE of Iraq. Understanding the static elastic modulus of host rocks is crucial because of the design and construction of numerous geotechnical structures and the presence of large hydrocarbon reservoirs in this formation. To determine the elastic modulus of intact rocks, the uniaxial compressive strength test is typically used. However, in jointed rocks and deep areas, where obtaining samples may be challenging, costly, or even impossible, correlations between static-dynamic elastic modulus (Es — E d) is more frequently employed. Although some scholars have proposed correlations between Es - Ed, they had determined dynamic modules based on the ultrasonic test. In the aforementioned test, intact samples are used and the effect of discontinuities would not be considered; hence, the results cannot be considered as rock mass representative. In this study, to consider field geotechnical conditions, the dynamic modules were determined based on the downhole seismic test (DS) in a tunnel in located the west of Iran. Then from the results of static elastic modulus, which were obtained from core samples, a linear correlation was proposed between Es — Ed. The root-mean-square error and variance accounted showed that the predicted static elastic modulus by the proposed correlation is more accurate to a large extent. In addition, unlike the ultrasonic-based Ed, the results showed that the DS-based Ed is less than Es.

2

Multicriteria Decision-Making in Complex Quality Evaluation of Ladies Dress Material

Misra Srabani, Salacova Jana, Militky Jiri

Autex Research Journal

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2020

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Vol. 20, no. 3

288--298

EN

Quality is the essence of any product for consumer satisfaction. However, different people have different perception of quality. Eventually the definition of quality varies from product to product and thus it is much more complex in textile clothing material evaluation. The end use application of a specific clothing material determines what should be the parameters of quality evaluation. Thus, the evaluation based on subjective assessment becomes unpredictable and unquantifiable. Quality for dress materials is not simply a physical parameter but something called as psycho-physical parameter. In recent times, many objective evaluation systems have been developed to evaluate the apparel grade textile materials with regard to their quality parameters. However, the evaluation does not involve enough statistical treatment of data so as to obtain a parametric weighted characterization of complex quality. The current work deals with parametric approach to complex quality evaluation based on multicriteria decision-making approach for ladies dress materials. The ladies dress materials are of numerous varieties and choices across the globe. The selection and marketing of these kinds of textile materials need to be given proper emphasis as it depends not only on physical parameters but also on climate, geography, ethnic group, market trend, age group, gender, and many such complex parameters, which are not quantifiable in absolute terms. In this study, woven fabrics used for ladies dress materials are collected from the market and they were evaluated for the consumer-oriented property parameters. A parametric approach is adopted to quantify the overall quality of these dress materials. Various objective techniques were used to evaluate the comfort and esthetic parameters. A complex quality index (CQI) was estimated with weighted combination of all the contributing parameters and total quality index was calculated. Selected consumers with different education level, age, and gender were interviewed to get a statistic of their opinion about quality parameters preferred by them. This complex quality index/degree of satisfaction shows very high correlation with subjective judgment. A CQI can be evaluated for each kind of clothing material looking into their applications.

3

Zastosowanie wielołączowego systemu transmisji danych Link 16 w wyrobach PIT-RADWAR S.A.

Dróżdż H., Sędek E.

Elektronika : konstrukcje, technologie, zastosowania

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2018

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Vol. 59, nr 1

10--16

PL

Artykuł prezentuje wielołączowy system transmisji danych Link 16 (NATO SECRET) jako przykład systemu wspomagającego świadomość sytuacyjną na polu walki, wykorzystywanego w systemach taktycznych państw sojuszniczych. Jednocześnie artykuł omawia szczegółowo technologię i technikę systemu pracującego ze zwielokrotnieniem czasowym TDMA oraz zabezpieczenie przetwarzania informacji niejawnych w tym systemie. Ponadto zaprezentowane zostały przykłady zastosowania wariantów rozwiązań systemu Link 16 w dużym wyrobie PIT-RADWAR S.A., którym jest system Nadbrzeżnego Dywizjonu Rakietowego Marynarki Wojennej RP.

EN

The paper presents multilink system data transmission Link 16 (NATO SECRET) as an example of the SADL Systems (Situational Awareness Data Link Systems), which is used in the tactical Systems of allied countries. The paper detaily discusses the technology and technique TDMA systems and also processing technique of the classified information in this system. Additionaly paper presents the examples of different solutions of the Link 16 system in large, current product of PIT-RADWAR S.A., which is Coastal Defence System/Naval Strike Missiles at Polish Navy.

4

Multi-spark modeling of very fast transient overvoltages for the purposes of developing HV and UHV gas-insulated switchgear and of conducting insulation co-ordination studies

Szewczyk M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2017

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Vol. 65, nr 6

871--882

EN

Very fast transient overvoltages (VFTO) originate from steep voltage breakdowns in SF6 gas that are inherent to operation of any switching device of the gas-insulated switchgear (GIS) type. For power stations with voltage ratings exceeding 500 kV, the ratio between equipment rated- and withstand-voltage levels becomes relatively low, which causes the VFTO peak values to reach the component’s insulation withstand-voltage levels, thus becoming a design factor for high- and ultra-high voltage GIS. While well-established approach to VFTO analyses involves only single VFTO events (the so-called single-spark approach), there is often the need to analyze the entire VFTO generation process, for which the multi-spark approach to VFTO modeling is to be employed. The multi-spark approach allows one to evaluate the VFTO impact on the GIS disconnector design along with the impact of the VFTO on selection and dimensioning of the VFTO damping solutions. As the multi-spark approach to VFTO modeling is now being increasingly used in UHV GIS developments as well as for the insulation co-ordination studies of power stations, the present paper is motivated by the need to report on the VFTO multi-spark modeling approach and to lay a common ground for development works that are supported extensively with VFTO simulations. The paper presents physical assumptions and modeling concepts that are in use in such modeling works. Development of the multi-spark GIS disconnector model for VFTO simulations is presented, followed by an overview of examples of the model application for the GIS development works and for insulation co-ordination studies.

5

A Hilbert Transform Based Algorithm for Detection of a Complex Envelope of a Power Grid Signals : an Implementation

Wetula A.

Electrical Power Quality and Utilisation. Journal

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2008

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Vol. 14, iss. 2

13--18

EN

The paper presents an algorithm for detection of a complex envelope of power grid signals. The algorithm is based on a Hilbert transform. It was prepared for an analysis of a lowfrequency disturbances, but can also be used as a compex envelope source for other applications. An implementation of the algorithm in a digital signal processor was made to proof an ability of a realtime operation. Analyses with various numerical representations and input signal quantization were done. Execution times on a DSP were measured. Tests proved that the presented algorithm is able to analyze power grid signals in a real-time with satisfying performance and uncertainty.