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Comparative analysis of the effects of gunpowder and plasma ignition in closed vessel tests

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Defence Technology（防务技术） 2019年第5期15卷 668-673页

作者： radoslaw Trebinski Zbigniew Leciejewski Zbigniew Surma Jakub Michalski Military University of Technology Department of Mechatronics and Aerospace

This paper presents the results of a comparative investigation into the effects of the ignition method on the ballistic properties of a single-base gun propellant,as determined via closed vessel *** gunpowder ignition and plasma jet ignition methods were used,and differences in the ignition time were *** influence of the ignition method on the dynamic vivacity is *** is shown that this influence is significant in the first phase of the combustion process,and with respect to the low values of the loading *** the second phase of the combustion process,and for large values of the loading density,the dynamic vivacity plots for the two ignition methods *** the burning law,close values of the exponent were obtained for the two ignition *** dynamic vivacity plots determined for plasma ignition reveal stronger dependence on the loading density than those determined for gunpowder *** conclusion is that plasma ignition is not a solution to the problems inherent to the process of determining the ballistic properties of propellants,which results in deviation of the burning process from the geometric burning law.

关键词： Closed vessel test Gun propellant Gunpowder ignition Plasma ignition

Investigations on influence of rifle automatics system action on values of energetic efficiency coefficient of muzzle brakes

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Defence Technology（防务技术） 2022年第10期18卷 1741-1747页

作者： radoslaw Trebinski Zbigniew Leciejewski Jacek Kijewski Dawid Gozdzik Damian Szupienko Military University of Technology Faculty of MechatronicsArmament and Aerospaceul.Gen.S.Kaliskiego 200-908WarszawaPoland

The objective of the paper was to compare values of the muzzle brake efficiency coefficient for a rifle with active or inactive automatics *** laboratory stand designed for investigating the recoil process was *** motion of the rifle was detected by the use of the laser interferometer and the optical *** recoil velocity time courses were determined by smoothing and differentiation of experimental position *** results of the experiments indicated that in the case of an active automatics system two values of the recoil velocity can be used for calculation of the energetic efficiency coefficient:the maximum recoil velocity and the final recoil velocity at the end of the automatics action *** values of the coefficient,calculated using these two values of the recoil velocity,distinctly ***,it was shown that their values indicate the same relation between the efficiency of various muzzle *** value of the efficiency coefficient,determined on the basis of the final recoil velocity value,is practically the same as that determined on the basis of the final recoil velocity value for the rifle with an inactive automatics system.

关键词： Ballistics Muzzle brakes Automatic rifle Efficiency Recoil velocity

Myocardial infarction with ST-segment elevation in old patient with history of takotsubo syndrome

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Journal of Geriatric Cardiology 2018年第5期15卷 376-378页

作者： Momka Budnik Janusz Kochanowski radoslaw Piatkowski Robert Kowalikl Janusz Kochman Grzegorz Opolski First Chair and Department of Cardiology Medical University of Warsaw 1a Banacha Street 02-097 Warsaw Poland Department of Noninvasive Cardiology and Hypertension Central Clinical Hospital of the Ministry of the Interior and Administration Wotoska 137 02-507 Warsaw Poland

Takotsubo syndrome （TTS） is a rare condition that af- fects mainly aging women. TTS was first reported in 1990r and is characterized by clinical symptoms, ECG changes and regional wall motion abnormalities without changes in the coronary arteries. However, some reports admit the pos- sibility of coexistence of TTS and coronary artery disease. We present a patient who had not had any changes in coro- nary arteries until four years later when she had myocardial infarction associated with right coronary artery narrowing, despite the fact that the risk factors of coronary heart disease were closely monitored.

关键词： Myocardial infarction Recurrence of disease Takotsubo syndrome

Simultaneous surgery for critical aortic stenosis and gastric cancer:A case report

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World Journal of Gastroenterology 2010年第9期16卷 1161-1164页

作者： Jacek Zielinski radoslaw Jaworski Rafal Pawlaczyk Maciej Swierblewski Pawel Kabata Janusz Jaskiewicz Jan Rogowski Department of Surgical Oncology Medical University of Gdansk Department of Cardiovascular Surgery Medical University of Gdansk

We describe simultaneous surgery performed on a 71-year-old woman with critical aortic stenosis and gastric cancer that were diagnosed at the same *** patient qualified for simultaneous surgery for both these *** early outcome was *** is a lack of standards for treatment of patients with coexistence of two life-threatening *** discuss surgical tactics and potential benefits of such management.

关键词： Aortic stenosis Aortic valve replacement Gastric cancer Gastric resection

Wavelet Transform in Vibroacoustic Diagnostics of Combustion Engines

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Engineering（科研） 2019年第7期11卷 395-406页

作者： radoslaw Wrobel Andrzej Kazmierczak Wroclaw University of Science and Technology Wroclaw Poland

This article discusses the use of wavelet decomposition in the diagnostics of vibrometric signals of an engine. Apart from presenting the possibility of using wavelets in diagnostics, the authors take up the subject of the applicability range of processing for stationary signals, which until now has been reserved for non-stationary signals. A unified definition of signal stationarity has been proposed, which is not based on statistics. The authors presented methods of wavelet decomposition of a vibrometric signal of combustion engine vibrations, measured with the use of LDV (Laser Doppler Vibrometry). Laser measurements allow for studying an object without “touching” its housing. Basing on the relative velocity of engine vibrations, the authors indicate how reliable vibrations are in diagnostics. Despite higher costs, this measurement method gives better results (for specific cases) than acoustic studies. Transform-wavelet decomposition is a solution hardly ever used in machine diagnostics;it is more often applied in medicine and image recognition. The authors presented the differences that can be obtained for different levels of decomposition, and also presented the impact on the engine condition assessment through the use of filtering (windowing) the signal before decomposition.

关键词： DSP Wavelet LDV Combustion Engine

Comparison Research of Bed Joints Construction and Bed Joints Reinforcement on Shear Parameters of AAC Masonry Walls

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Journal of Civil Engineering and Architecture 2016年第12期10卷 1329-1343页

作者： radoslaw Jasinski Lukasz Drobiec Building Structures Department Faculty of Civil Engineering Silesian University of Technology Gliwice 44-100 Poland

The work presents the results of tests on the shear parameters of walls made of AAC （autoclaved aerated concrete, fb = 4.0 N/mm2） on the system mortar for thin M5 and M10 joints （fm = 6.1 N/mm2 and fro = 11.9 N/mm2） and on polyurethane glue and also walls without mortar （dry masonry）. The wall compression strength （on mortar M5 class）（per EN 1052-1：2000） amounted tofc,mv= 2.97 N/mm2 （fk = 2.48 N/mm2）, elastic modulus was Ecru = 2,040 N/mm2. Various structure of bed joints and head joints were applied and the following were used as reinforcement： steel trusses of EFZ 140/Z 140 type （Z1 type） and meshes made of plastics （Z2 type）. Based on the tests carried out with regard to unreinforced elements, it was shown that the filling in of head joints with mortar had an advantageous effect on the values of cracking and destruction stresses. While, with the use of reinforcement, advantageous increase of stress was obtained only when the mortar was laid twice on both bed surfaces of masonry units. The application of reinforcement in the bed joints when the mortar was laid only on one bed joints surface of the masonry units reduced the values of cracking and destruction stresses in relation to the values obtained in the unreinforced walls.

关键词： AAC thin layer mortar joints masonry shear strength reinforced shear walls.

Coexistence of proangiogenic potential and increased MMP-9, TIMP-1, and TIMP-2 levels in the plasma of patients with critical limb ischemia

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2019年第8期20卷 687-692页

作者： radoslaw Wieczór Anna Maria Wieczór Arleta Kulwas Grzegorz Pulkowski Jacek Budzyński Danuta Rosc Department of Pathophysiology Faculty of Pharmacy Nicolaus Copernicus University in Toruń Ludwik Rydygier Collegium Medicum in Bydgoszcz Bydgoszcz PL 85-094 Poland Clinic of Vascular and Internal Medicine Dr Jan Biziel University Hospital No. 2 in Bydgoszcz Bydgoszcz PL 85-168 Poland Department of Vascular and Internal Medicine Faculty of Health Sciences Nicolaus Copernicus University in Toruń Ludwik Rydygier Collegium Medicum in Bydgoszcz Bydgoszcz PL 85-168 Poland

The objective of this study was to assess the angiogenic potential expressed as a quotient of vascular endothelial growth factor A (VEGF-A), as an indicator of proangiogenic activity, and the circulating receptors (soluble VEGF receptor protein R1 (sVEGFR-1) and sVEGFR-2), as indicators of the effect of angiogenic inhibition, depending on the concentrations of matrix metalloproteinase 2 (MMP-2) and MMP-9 and their tissue inhibitor 1 (TIMP-1) and TIMP-2 in the plasma of patients with lower extremity artery disease (LEAD). These blood parameters in patients with intermittent claudication (IC) and critical limb ischemia (CLI) were compared for select clinical and biochemical features. Stimulation of angiogenesis in the plasma of individuals with LEAD was evident as indicated by the significant increase in VEGF-A concentration along with reduced inhibition depending on circulating receptors sVEGFR-1 and sVEGFR-2. Critical ischemia was associated with higher VEGF-A, MMP-9, TIMP-1, and TIMP-2 concentrations than in the case of IC.

关键词：严重肢体缺血间歇性跛行血管内皮生长因子金属蛋白酶

Silicon-Basing Ceramizable Composites Containing Long Fibers

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Journal of Materials Science and Chemical Engineering 2013年第5期1卷 43-48页

作者： Zbigniew Pedzich Rafal Anyszka Dariusz MBieliński Magdalena Ziabka radoslaw Lach Magdalena Zarzecka-Napierala Department of Ceramics and Refractory Materials AGH-University of Science&TechnologyKrakowPoland Institute of Polymer and Dye Technology Lodz University of TechnologyLodzPoland

Ceramization is a phenomenon which assures compactness of polymer-based composites in the case of their thermal degradation caused by open fire or exposure at high temperatures. This phenomenon is based on preventing volatiles of thermal decomposition of silicone rubber from evacuation by creation of ceramic layer. This ceramized structure is composed of mineral filer particles, connected by fluxing agent—glassy phase. The ceramic barrier created during firing is aimed to protect copper wire inside the cable from melting, being additionally strong enough to maintain integrity of electrical circuit. The paper presents experimental data on mechanical properties of silicone rubber composites strengthened additionally with long fibers of different types—aluminosilicate and polyamide (Kevlar) ones. Fibers were introduced into composites in oriented way. Mechanical properties were investigated taking into account fiber orientation anisotropy. Ceramization process of composites was described by observation of morphology and strengthen measurements of samples fired at 1000°C.

关键词： Silicone Rubber Ceramization Composites Polyamide Fibers Aluminosilicate Fibers

The oldest patient with takotsubo cardiomyopathy

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Journal of Geriatric Cardiology 2015年第5期12卷 588-589页

作者： Monika Budnik radoslaw Piatkowski Janusz Kochanowski Renata Glowczynska Dariusz Gorko Robert Kowalik Arkadiusz Pietrasik Grzegorz Opolski Department of Cardiology Medical University of Warsaw Warsaw Poland

Takotsubo cardiomyopathy （TTC） is a rare condition that affects mainly aging women. According to a retrospective review, patients with TTC accounted for approximately 2% of all the patients with suspected acute coronary syndrome （ACS）. A few reports indicated that the average age of TTC patients was 68 years, although children or young adults may also be affected. In US and Europe, a number of contemporary TTC studies report that 90% of patients with TTC are women aged 65-70 years. Meta analysis showed that the age ranged from 10 to 89 years.

关键词： Acute coronary syndrome Electrocardiogram Takotsubo cardiomyopathy