109 research outputs found
Wojny cybernetyczne jako element niekonwencjonalnej konfrontacji międzypaństwowej. Pragmatyczna rzeczywistość, nieunikniona przyszłość
The aim of this article is to examine the phenomenon of cyber warfare as part of an unconventional confrontation between states in contemporary international relations. The construction of this study, dictated by an attempt to achieve a response on the above research subject, brought the author to adopt the following structure. The first part of the work presents the development of computer hardware and networks together with visualizing the cyberspace importance. Next, the conditions of this theoretical issues, in particular, the basic determinants categories of network attacks and their classifications are presented. Further, the practical aspects of the application of those attacks are shown, taking a point of view specific casus i.e. Kosovo, China, Estonia, Georgia and Iran. At the end, the cyberwars were under consideration including the differences, similarities and lessons learned for the future.Celem niniejszego artykułu jest zbadanie zjawiska wojny cybernetycznej, jako elementu niekonwencjonalnej konfrontacji międzypaństwowej we współczesnych stosunkach międzynarodowych. Konstrukcja niniejszej pracy, podyktowana próbą osiągnięcia odpowiedzi na powyższy temat badawczy, sprowadziła autora do przyjęcia następującej struktury. W pierwszej części pracy, przedstawiono rozwój sprzętu komputerowego i sieci informatycznych wespół z uwidocznieniem znaczenia cyberprzestrzeni. Następnie, opisano uwarunkowania teoretyczne przedmiotowej problematyki, w szczególności podstawowe determinanty, kategorie ataków z sieci oraz ich klasyfikacje. W dalszej kolejności, ukazano praktyczne aspekty zastosowania powyższych ataków biorąc za punkt widzenia konkretne casusy tj. Kosowa, Chin, Estonii, Gruzji oraz Iranu. Na koniec zaś poddano pod rozwagę cyberwojny poruszając różnice i podobieństwa oraz płynące z nich wnioski na przyszłość
Renewable Fuels for Internal Combustion Engines
The continuous need for systematization and open dissemination of knowledge on Renewable Fuels intended for use in Internal Combustion Engines forms the premise of the presented Special Issue titled “Renewable Fuels for Internal Combustion”. Experts in the field were encouraged to share their latest findings in the form of original research papers, case studies, or short reviews. Works targeting all aspects of the value chain were considered necessary, including the following: (liquid and gaseous) fuel production process, upgrading (catalytic and fractional blending), up to end, valorization in combustion engines (conventional and advanced concepts). Finally, techno-economic analyses aiming to valorize the value chain holistically were warmly encouraged to submit papers in this Special Issue of the Energies Journal. In this book, the reader will find successful submissions that present the latest findings from the discussed research field, encapsulated into nine chapters.© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article
distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).fi=vertaisarvioimaton|en=nonPeerReviewed
An experimental analysis of performance and exhaust emissions of a CRDI diesel engine operating on mixtures containing mineral and renewable components
The manuscript presents a comparative analysis of the performance and emission characteristics of a compression ignition engine equipped with a Common Rail injection system. The engine is fueled with diesel-biodiesel mixtures containing 25% and 50% share (by volume) of renewable components. Conventional diesel is used as a reference. Turkey lard and rapeseed oil are used as raw materials and subjected to the single-stage transesterification process to obtain methyl esters. The experiments are performed on a medium-duty, turbocharged, inter-cooled, Common Rail Direct Injection (CRDI) diesel engine. This study concentrates on one engine speed of 1500 rpm, typical for gen-set applications, and mid-load range from 100 Nm to 200 Nm. The scope of measurements covers the analysis of exhaust gasses concentration and engine efficiency parameters. In addition, the in-cylinder pressure measurements are performed in order to provide insight into the differences in combustion characteristics between examined fuel mixtures. The study reveals that the addition of the renewable component to fuel mixture positively affects a number of examined performance parameters as well as decreases the concentration of the examined toxic exhaust components, in the majority of cases.fi=vertaisarvioitu|en=peerReviewed
Создание Третьей Бригады Легионов Польских. Обстоятельства создания и обзор снаряжения
The aim of this work is not be exhaustive, but merely a subjective show the history of military formations existing in the years 1915-1917 he was the Third Brigade of the Polish Legions. On the basis of archival materials and scientific literature the author presents the constitution of the unit, which played an important role in the struggle for Polish independence in the First World War. The work is presented in both aspects of the purely military and political background related to the struggle for Polish Legions character. Initially, the author puts forward for consideration a preliminary reflection. Then present the formation of Polish organization of shooting in Galicia. In the next part discusses the circumstances surrounding the creation and the beginnings of the Polish Legions and the genesis of the Third Brigade of the Polish Legions. At the end of the focuses its attention on uniforms and equipment Legions
Analysis of noise inside bus of hybrid bus vehicles
The article presents the results of noise measurements during a control passage recorded in the interior of a bus with a serial hybrid drive. The noise was recorded in a continuous mode, and the course was adjusted for the pressure level and spectrogram in the field of time and frequency
Application of vibration signal in the diagnosis of IC engine valve clearance
The article describes a concept of a non-invasive method for diagnosing the size of valve clearance in internal combustion engines, based on the analysis of engine surface vibration signals using artificial neural networks. The applicability of the method was tested on a single-cylinder compression-ignition engine with a low power rating, which had an OHV timing gear, acting indirectly on the valves, and manual adjustment of valve clearance. The method uses as diagnostic signals the readings of vibration sensors, which record the acceleration of engine head movement as a function of the angle of rotation of the crankshaft, with pre-set valve clearance values measured in a cold condition. From among the signals recorded, components corresponding to the impact of rocker arms against valve stems were identified and low-pass filtered in order to eliminate measurement interference. A classifier of selected features of the signals processed was constructed using artificial neural networks. This classifier recognizes signals generated by engines with correct valve clearance as well as those with too much and too little valve clearance
Application of the vibration signal in the diagnosis of the valve clearance of an internal combustion engine
The article describes a concept of a non-invasive method for diagnosing the size of the valve clearance of combustion engines based on an analysis of engine surface vibration signal using artificial neural networks. The applicability of the method was tested on a single-cylinder compression-ignition engine with a low power rating, which had an OHV timing gear acting indirectly on the valves and manual adjustment of valve clearance. The method uses as diagnostic signals the readings of vibration sensors, recording the acceleration of engine head movement as a function of the angle of rotation of its crankshaft, with pre-set values of valve lash measured in a cold condition. From among the recorded signals, components corresponding to the impact of rocker arms on valve stems were identified, and then these components were subjected to low-pass filtering in order to eliminate measurement interference. Using artificial neural networks, a classifier of selected measures of the processed signals was constructed, which recognizes signals generated by engines with correct valve clearance as well as those with too much and too little valve clearance
Combustion of Gaseous Alternative Fuels in Compression Ignition Engines
The problem of alternative fuels for combustion engines has been growing in importance recently. This is connected not only with decreasing fossil fuel resources, but also with the growing concern for the natural environment and the fight against global warming. This paper discusses the possibility of utilizing alternative gaseous fuels in compression-ignition engines, using dual-fuel, gas-liquid operation strategy. Current state of the art of this technology had been introduced, along with its benefits and challenges to be countered. The discussion had been supported by authors own research experience on dual-fuel engines. The latest results of research on the impact of gas composition on combustion process in the Common Rail dual fuel engine had been presented, at the same illustrating the environmental benefits of using gaseous fuels. The Utilization of gaseous fuels with varying composition was illustrated systematically, starting with natural gas. The possibility of using fuels with lower content of methane (the so-called low-calorie gases) was shown by the impact of depleting natural gas with carbon dioxide. Industrial gases, such as syngas contain a large amount of hydrogen, carbon monoxide or higher hydrocarbons (ethane, propane). The possibility of fueling CI engines with these gasses was presented by the influence of enriching natural gas with mentioned components. The results cover engine dynamometer tests for different operating conditions with the analysis of the combustion process and detailed emission measurements discussion. The results of experimental studies were supplemented by simulation results, using mathematical models, developed by the authors for multi-fuel enginesr
NF-κB-related decrease of glioma angiogenic potential by graphite nanoparticles and graphene oxide nanoplatelets
Abstract Gliomas develop an expanded vessel network and a microenvironment characterized by an altered redox environment, which produces high levels of reactive oxygen species (ROS) and reactive nitrogen species (RNS) that fuel its growth and malignancy. ROS and RNS can influence tumor cell malignancy via the redox-regulated transcription factor NF-κB, whose activation is further regulated by the mutation status of p53. The objective of this study was to assess the influence of graphite nanoparticles (NG) and graphene oxide nanoplatelets (nGO) on the angiogenic potential of glioma cell lines with different p53 statuses. Nanoparticle treatment of glioma cells decreased the angiogenesis of human umbilical vein endothelial cells (HUVEC) cocultured with U87 (p53 wild type) and was not effective for U118 (p53 mutant) cells. Nanoparticle activity was related to the decreased level of intracellular ROS and RNS, which downregulated NF-κB signaling depending on the p53 status of the cell line. Activation of NF-κB signaling affected downstream protein levels of interleukin 6, interleukin 8, growth-regulated oncogene α, and monocyte chemotactic protein 1. These results indicate that the activity of NG and nGO can be regulated by the mutation status of glioma cells and therefore give new insights into the use of nanoparticles in personalized biomedical applications regarding glioma angiogenesis and its microenvironment
Evaluating the Influence of Cetane Improver Additives on the Outcomes of a Diesel Engine Characteristics Fueled with Peppermint Oil Diesel Blend
This paper aims to evaluate the impact of cetane improvers on the combustion, performance
and emission characteristics of a compression ignition engine fueled with a 20% peppermint bio-oil/diesel blend (P20). It is hypothesized that the low viscosity and boiling point of peppermint oil could improve the atomization characteristics of the fuel. However, the usage of peppermint oil is restricted due to its low cetane index. To improve this, Diethyl Ether (DEE) and Di-tertiary Butyl Peroxide (DTBP) are added to the P20 blend. The tests are performed in a single-cylinder naturally aspirated water-cooled diesel engine and results indicate that NOx emission for P20 + DEE and P20 + DTBP is decreased by 10.4% and 9.8%, respectively, when compared to P20 at full load condition. Among these two cetane improvers, DTBP is more effective in reducing the CO, HC and smoke emission and the performance of the engine was reported to be higher for P20 + DTBP blends.© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article
distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).fi=vertaisarvioitu|en=peerReviewed
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