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替代燃料列车的耐撞性研究

国外铁道机车与动车 2024年第2期 19-20页

作者： [美]przemyslaw Rakoczy 焦国超(译) 不详

为保证替代燃料及电池驱动列车的安全性,需要对列车耐撞性能要求进行重新评价及更新。美国联邦铁路局(FRA)为此在运输技术中心(TTC)进行了一系列研究与试验。文章对试验研究情况作了介绍,提出还需进行进一步的试验及模拟,以确保替代燃... 详细信息

为保证替代燃料及电池驱动列车的安全性,需要对列车耐撞性能要求进行重新评价及更新。美国联邦铁路局(FRA)为此在运输技术中心(TTC)进行了一系列研究与试验。文章对试验研究情况作了介绍,提出还需进行进一步的试验及模拟,以确保替代燃料及电池驱动技术的安全性等同于甚至高于传统技术。

关键词：铁路减排替代燃料 BESS 耐撞性能 TTC

Partnership for eXtreme Xtallography (PX^(2))—A state-of-the-art experimental facility for extreme-conditions crystallography: A case study of pressure-induced phase transition in natural ilvaite

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Matter and Radiation at Extremes 2022年第2期7卷 62-71页

作者： Jingui Xu Dongzhou Zhang Sergey N.Tkachev przemyslaw K.Dera School of Ocean and Earth Science and Technology Hawai’i Institute of Geophysics and PlanetologyUniversity of Hawai’i at ManoaHonoluluHawaii 96822USA Center for Advanced Radiation Sources University of ChicagoChicagoIllinois 60437USA

Single-crystal x-ray diffraction(SCXRD)is an important tool to study the crystal structure and phase transitions of crystalline materials at elevated pressures.The Partnership for eXtreme Xtallography(PX^(2))program at the GSECARS 13-BM-C beamline of the Advanced Photon Source aims to provide state-of-the-art experimental capabilities to determine the crystal structures of materials under extreme conditions using SCXRD.PX^(2) provides a focused x-ray beam(12318μm^(2))at a monochromatic energy of 28.6 keV.High-pressure SCXRD experiments are performed with a six-circle diffractometer and a Pilatus3 photon-counting detector,facilitated by a membrane system for remote pressure control and an online ruby fluorescence system for pressure determination.The efficient,high-quality crystal structure determination at PX^(2) is exemplified by a study of pressure-induced phase transitions in natural ilvaite[CaFe^(2+)_(2 )Fe^(3+)Si_(2)O_(7)O(OH),P2_(1)/a space group].Two phase transitions are observed at high pressure.The SCXRD data confirm the already-known ilvaite-I(P2_(1)/a)→ilvaite-II(Pnam)transformation at 0.4(1)GPa,and,a further phase transition is found to occur at 22.8(2)GPa where ilvaite-II transforms into ilvaite-III(P2_(1)/a).The crystal structure of the ilvaite-III is solved and refined in the P2_(1)/a space group.In addition to the ilvaite-I→ilvaite-II→ilvaite-III phase transitions,two minor structural modifications are observed as discontinuities in the evolution of the FeO6 polyhedral geometries with pressure,which are likely associated with magnetic transitions.

关键词： phase extreme transitions

Passive radiant cooling without sacrificing the aesthetics of objects

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Light(Science & Applications) 2022年第7期11卷 1339-1340页

作者： przemyslaw Jacek Dereń Institute of Low Temperature and Structure Research PAS ul.Okólna 2WroclawPoland

Photonic-engineered passive radiative cooling built into decorative climate-controlled enclosures reduces the active power consumption of the existing enclosure without sacrificing its aesthetics.

关键词： icing radiative enclosure

Digital Signatures for e-Government - a Long-Term Security Architecture

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China Communications 2010年第6期7卷 64-70页

作者： przemyslaw Blaskiewicz przemyslaw Kubiak Miroslaw Kutylowski Wroctaw University of Technology Institute of Mathematics and Computer Science ul. Janiszewskiego 14a 50-372 Wroclaw. Poland

The framework of digital signature based on qualified certificates and X.509 architecture is known to have many security risks. Moreover, the fraud prevention mechanism is fragile and does not provide strong guarantees that can be necessary for flow of legal documents. Mediated signatures have been proposed as a mechanism to effectively disable signature cards. In this paper we propose further mechanisms that can be applied on top of mediated RSA, compatible with the standard format, but providing security guarantees even in the case when RSA becomes broken or the keys are compromised. The solution is immune tokleptographic attacks as only deterministic algorithms are used on user's side.

关键词：数字签名安全体系结构电子政府确定性算法安全隐患合格证书框架基础标准格式

Computational Modelling of Retrofitting a Coal Fired Boiler Type OP-230 for Predicting NOX Reduction

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Journal of Thermal Science 2018年第5期27卷 433-439页

作者： MOTYL przemyslaw LACH Jan Faculty of Mechanical Engineering Kazimierz Pulaski University of Technology and Humanities in RadomRadom 26-600poland Faculty of Engineering Management Bialystok University of TechnologyKleosin 16-001 Poland

This study focuses on a CFD modelling of biomass-derived syngas co-firing with coal in an older mid-sized PC-fired boiler of type OP-230 with low-emission burners on the front wall. The simulations were performed to determine whether the boiler can be retrofitted for the fulfilment of the prospective environmental protection regulations relating to levels of NO_X emissions. The improvement of the air staging via the dual-fuel technique was based on the indirect co-firing technology. The impact of two arrangements of dedicated syngas nozzles(below and above the existing coal burners), two syngas compositions and two heat replacements(5% and 15%) on the course of thermal processes in a furnace was tested. The reductions in NO_X emissions were predicted relative to the baseline when only coal is combusted. The highest reduction of about 38% was achieved with the syngas nozzles below the existing coal burners and 15% heat replacement. This arrangement of nozzles offers the residence time sufficient to co-fire coal with waste derived syngas. A lower reduction in NO_X emissions was obtained with the nozzles above the burners as the enlargement of local fuel rich zone near syngas injection becomes significant for 15% heat replacement. Results provide for the decreasing impact of methane content along with the increase of syngas heat input. The avoided CO_2 emissions through the syngas indirect co-firing with coal in the boiler are linear function of heat replacements.

关键词：锅炉类型 NOX 预言建模翻新煤计算生物资源

Determination of the Influence of c-BN+h-BN Coating Structure on Brittleness

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材料热处理学报 2004年第5B期25卷 888-893页

作者： Maciej Kupczyk Adam Lejwoda przemyslaw Cieszkowski przemyslaw Libuda Poznan University of Technology Institute of Mechanical Engineering Poznan PolandPoznan University of Technology Institute of Mechanical Engineering Poznan PolandPoznan University of Technology Institute of Mechanical Engineering Poznan PolandPoznan University of Technology Institute of Mechanical Engineering Poznan Poland

In the article is presented the brittleness study of boron nitride coatings deposited on cutting edges made of cemented carbides by the pulse-plasma method (PPD). Influences of the structure (density, pores, microcracks) of coating material on the brittleness and on selected technological parameters of boron nitride formation by PPD method particularly taking into account discharge voltage on brittleness are shown. Differences between values of both ai(300) and "1(5oo) coefficients characterized susceptibility to coatings cracking of investigated coating manufactured using different values of discharge voltage were defined. Results of an investigations have been confirmed usefulness of Palmqvist’s method for measurement of coating susceptibility to brittle cracking.

关键词：耐磨覆层 PVD 脆性氮化硼涂层

The Almost Sure Central Limit Theorems for the Maxima of Sums under Some New Weak Dependence Assumptions

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Acta Mathematica Sinica,English Series 2013年第3期29卷 429-448页

作者： Marcin DUDZINSKI przemyslaw GORKA Faculty of Applied Informatics and Mathematics Warsaw University of Life Sciences (SGGW) Department of Mathematics and Information Sciences Warsaw University of Technology

We prove the almost sure central limit theorems for the maxima of partial sums of r.v.＇s under a general condition of dependence due to Doukhan and Louhichi. We will separately consider the centered sequences and the... 详细信息

关键词： Almost sure central limit theorem new weakly dependent random variables maxima ofpartial sums Markov chains

Recent Advances in High Pressure and Temperature Rheological Studies

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Journal of Earth Science 2010年第5期21卷 495-516页

作者： Nadege Hilairet przemyslaw Dera Center for Advanced Radiation Sources The University of Chicago 5640 South Ellis Avenue Chicago Illinois 60637 USA

Rheological studies at high pressure and temperature using in-situ X-ray diffraction and imaging have made significant progresses in recent years, thanks to a combination of recent developments in several areas：（1） advances in synchrotron X-ray techniques, （2） advances in deformation devices and the abilities to control pressure, temperature, stress, strain and strain rates, （3） theoretical and computational advances in stress determination based on powder and single crystal diffraction, （4） theoretical and computational advances in modeling of grain-level micromcchanics based on elasto-plastic and visco-plastic self-consistent formulations. In this article, we briefly introduce the experimental techniques and theoretical background for in-situ high pressure, high temperature rheological studies, and then review recent studies of rheological properties of major mantle materials. Some currently encountered issues have prompted developments in single-crystal quasi-Laue diffraction for complete stress tensor determination and textural evolution of poly-phased composites based on X-ray microtomography. Future prospects are discussed.

关键词： rheology deformation composite synchrotron radiation high pressure and high temperature diffraction tomography.

Tourist boom and rural revival-Case study of Klodzko Region(SW Poland)

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Journal of Mountain Science 2022年第4期19卷 909-924页

作者： SZMYTKIE Robert LATOCHA Agnieszka SIKORSKI Dominik TOMCZAK przemyslaw KAJDANEK Katarzyna MIODONSKA Paulina Institute of Geography and Regional Development University of Wroclaw50-137 WroclawPoland Institute of Sociology University of Wroclaw51-149 WroclawPoland

Rural areas in the K?odzko Region were subject to a long-term depopulation,marginalization,and long-lasting socio-economic decline since the 19th century.In recent years,however,the study area has been subject to a shift in socio-economic trends that show rural revival.The main goal of the research is to assess the actual role of tourism in socio-economic revival of rural areas in the K?odzko Region.To determine the dynamics of the tourism function development,statistical data were used and an inventory of tourism beds in accommodation facilities was conducted.The results show that there was a substantial development of the tourism function in the study area and its most intense scale was noted in the depopulating villages,as evidenced by the increase in the numbers of tourism facilities and numbers of tourism beds.Therefore,it can be concluded that the development of tourism contributed to the limitation of negative socioeconomic processes in the area and,in the case of some villages,even to the reversal of these trends,which might testify to the rural revival.Moreover,the improvement of the socio-economic situation is visible also in the villages that do not have significant tourist values but are in the neighbourhood of tourism hotspots.This observation might be important for forecasting future development and planning of rural areas.

关键词： Rural revival Reviving village Tourism boom Economic recovery Marginal/peripheral areas