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Number of results: 8
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Abstract

The aim of this article is to present the author’s opinion about possible underwater natural gas pipeline monitoring using Polish Navy resources. Due to the bathymetrical characteristics of the pipeline equatorials the high efficiency and safe for the deck operators systems are expected to support the bottom survey and gas line monitoring. Time and engaged resources reduction are crucial factors in this kind of mission together with high probability of possible dangerous objects detection. The paper describes main threats for the underwater transportation line as a state energetic independence vital object (supplies diversification). An example of a threat caused by lost unmanned platform technologies near Nord Stream was presented and analyzed as well. The rapid development of unmanned maritime technologies (aerial, surface and subsurface) observed in the last decade creates new possibilities in maritime security/surveillance applications. The Polish mine counter measures assets which were equipped with sophisticated AUV’s as a part of the Polish Navy modernization process (new minehunters Kormoran IInd class deployable). The presented autonomous underwater vehicles (AUV) are equipped with advanced sonars and create new possibilities in the issue of effective threats detection/classification/ identification and neutralization. The main advantages of such solutions were pointed in the article with the crucial one based on time reduction as well as human – deck operators threats constraints. The first successes in the operational use of unmanned systems were reached during the military exercises (historical ordnance disposal) conducted on historical mine laying areas. This creates good possibilities to train the unmanned system operators in live objects activity which improves skills and knowledge. Moreover, the double use applications of unmanned technologies both in defense and maritime security has been observed.
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Abstract

The natural gas supply is used from Russia Federation as a political instrument in the geopolitical and territorial conflict with Ukraine. The effectiveness of Russian strategy towards Ukraine is due to the fact that power in Kiev is also exercised by the pro-Russian politicians and supported on the part of Ukrainian oligarchs. The two countries are interdependent in terms of energy by means of the existing gas infrastructure and long-term contracts, because Ukraine guarantees the Russian Federation the transit of natural gas to Europe through its system of transmission gas pipelines, and Russia pays for the transit and used to supply the agreed amount of gas to Ukraine. For the first time – in 2016 – Ukraine didn’t import natural gas directly from the Russia Federation. This article attempts to obtain an answer to the research question, whether Ukraine actually strives to diversify its natural gas supply. What part of this policy is the Ukrainian political instrument in terms of Russia, and what part is the real political objective? Especially in the context of the gas contract between both States, ending in 2019. What role will be played the underground gas storage in the geopolitical struggle? Despite Nord Stream II the Russian Federation still needs the Ukrainian pipelines to fulfill contractual obligations in gas supplies to Europe. What are the strategic goals of the energy policy of Ukraine and Russia? The geopolitical as well as geo-economic theories will be applied. Moreover, a factor analysis as well as a decision-making analysis will be used. The political analysis method and the forecasting technique are applied to obtain, not only theoretical, but also practical input.
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Abstract

The aim of this paper is to present an in-pipe modular robotic system that can navigate inaccessible industrial pipes in order to check their condition, locate leakages, and clean the ventilation systems. The aspects concerning the development of a lightweight and energy efficient modular robotic system are presented. The paper starts with a short introduction about modular inspection systems in the first chapter, followed by design aspects and finalizing with the test of the developed robotic system.
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Abstract

This paper presents a geomagnetic detection method for pipeline defects using complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) and wavelet energy product (WEP) – Teager energy operator (TEO), which improves detection accuracy and defect identification ability as encountering strong inference noise. The measured signal is first subtly decomposed via CEEMDAN into a series of intrinsic mode functions (IMFs), which are then distinguished by the Hurst exponent to reconstruct the filtered signal. Subsequently, the scale signals are obtained by using gradient calculation and discrete wavelet transform and are then fused by using WEP. Finally, TEO is implemented to enhance defect signal amplitude, completing geomagnetic detection of pipeline defects. The simulation results created by magnetic dipole in a noisy environment, indoor experiment results and field testing results certify that the proposed method outperforms ensemble empirical mode decomposition (EEMD)-gradient, EEMD-WEP-TEO, CEEMDAN-gradient in terms of detection deviation, peak side-lobe ratio (PSLR) and integrated side-lobe ratio (ISLR).
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Abstract

Three commercially available intercooled compression strategies for compressing CO2 were studied. All of the compression concepts required a final delivery pressure of 153 bar at the inlet to the pipeline. Then, simulations were used to determine the maximum safe pipeline distance to subsequent booster stations as a function of inlet pressure, environmental temperature, thickness of the thermal insulation and ground level heat flux conditions. The results show that subcooled liquid transport increases energy efficiency and minimises the cost of CO2 transport over long distances under heat transfer conditions. The study also found that the thermal insulation layer should not be laid on the external surface of the pipe in atmospheric conditions in Poland. The most important problems from the environmental protection point of view are rigorous and robust hazard identification which indirectly affects CO2 transportation. This paper analyses ways of reducing transport risk by means of safety valves.
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Abstract

A commercially available ASPEN PLUS simulation using a pipe model was employed to determine the maximum safe pipeline distances to subsequent booster stations as a function of carbon dioxide (CO2) inlet pressure, ambient temperature and ground level heat flux parameters under three conditions: isothermal, adiabatic and with account of heat transfer. In the paper, the CO2working area was assumed to be either in the liquid or in the supercritical state and results for these two states were compared. The following power station data were used: a 900 MW pulverized coal-fired power plant with 90% of CO2recovered (156.43 kg/s) and the monothanolamine absorption method for separating CO2from flue gases. The results show that a subcooled liquid transport maximizes energy efficiency and minimizes the cost of CO2transport over long distances under isothermal, adiabatic and heat transfer conditions. After CO2is compressed and boosted to above 9 MPa, its temperature is usually higher than ambient temperature. The thermal insulation layer slows down the CO2temperature decrease process, increasing the pressure drop in the pipeline. Therefore in Poland, considering the atmospheric conditions, the thermal insulation layer should not be laid on the external surface of the pipeline.
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Abstract

Mechanical properties of the pipeline samples that had been cut in annular and axial directions were investigated. The methodology of modeling and calculation of the real stress-strain state was described. The stable state during in the deformation process was defined. The results of the experimental researches were used as a test variant during examination of pipe strength.
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