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Science China Earth Sciences 2009年第1期52卷 1-11页

作者： Simon C. GEORGE adriana dutkiewicz Herbert VOLK John RIDLEY David J. MOSSMAN Roger BUICK Department of Earth and Planetary Sciences Macquarie University School of Geosciences University of Sydney CSIRO Petroleum Department of Geosciences Colorado State University Department of Geography Mount Allison University Department of Earth and Space Sciences & Astrobiology Program University of Washington

The observation of oil inclusions trapped prior to 2.0 Ga in Palaeoproterozoic rocks and the ability to obtain detailed molecular geochemical information from them provide a robust way for understanding the early biog... 详细信息

关键词： Palaeoproterozoic fluid inclusion oil biomarker blank

Form confers function:Case of the 3'X region of the hepatitis C virus genome

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World Journal of Gastroenterology 2018年第30期24卷 3374-3383页

作者： Mariola dutkiewicz Jerzy Ciesiolka Institute of Bioorganic Chemistry Polish Academy of SciencesPoznan 61-704Poland

At the 3' end of genomic hepatitis C virus(HCV) RNA there is a highly conserved untranslated region,the 3'X-tail,which forms part of the 3'*** region plays key functions in regulation of critical processes of the viral life *** 3'X region is essential for viral replication and *** is also responsible for regulation of switching between translation and transcription of the viral *** is some evidence indicating the contribution of the 3'X region to the translation efficiency of the viral polyprotein and to the encapsidation *** different secondary structure models of the 3'X region,based on computer predictions and experimental structure probing,have been *** is likely that the 3'X region adopts more than one structural form in infected cells and that a specific equilibrium between the various forms regulates several aspects of the viral life *** most intriguing explanations of the structural heterogeneity problem of the 3'X region came with the discovery of its involvement in long-range RNA-RNA interactions and the potential for homodimer *** article summarizes current knowledge on the structure and function of the 3'X region of hepatitis C genomic RNA,reviews previous opinions,presents new hypotheses and summarizes the questions that still remain unanswered.

关键词： Hepatitis C virus 3’UTR 3’X-tail 3’X region 3’X RNA RNA structure

An Improved Markov Model for IEEE 802.15.4 Slotted CSMA/CA Mechanism

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Journal of Computer Science & Technology 2009年第3期24卷 495-504页

作者：文浩林闯陈治佳尹浩何滔 Eryk dutkiewicz Department of Computer Science Tsinghua University Department of Physics and Engineering Macquarie UniversitySydneyAustralia

IEEE 802.15.4 protocol is proposed to meet the low latency and energy consumption needs in low-rate wireless applications, however, few analytical models are tractable enough for comprehensive evaluation of the protocol. To evaluate the IEEE 802.15.4 slotted CSMA/CA channel access mechanism in this paper, we propose a practical and accurate discrete Markov chain model, which can dynamically represent different network loads. By computing the steady-state distribution probability of the Markov chain, we obtain an evaluation formula for throughput, energy consumption, and access latency. Then we further analyze the parameters that influence performance including packet arrival rate, initial backoff exponent and maximum backoff number. Finally, NS2 simulator has been used to evaluate the performance of the 802.15.4 CSMA/CA mechanism under different scenarios and to validate the accuracy of the proposed model.

关键词： IEEE 802.15.4 Markov model CSMA/CA mechanism

Measurements in Situ and Spectral Analysis of Wind Flow Effects on Overhead Transmission Lines

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Sound & Vibration 2019年第4期53卷 161-175页

作者： Maciej dutkiewicz Marcela R.Machado UTP University of Science and Technology Bydgoszcz85-796Poland. University of Brasilia Brasilia70910-900Brazil.

In the paper an important issue of vibrations of the transmission line in real conditions was *** research was carried out by the authors of this paper taking into account the cross-section of the cable being in use on the transmission *** was performed for the modern ACSR high voltage transmission line with span of 213.0 *** purpose of the investigation was to analyze the vibrations of the power transmission line in the natural environment and compare with the results obtained in the numerical *** was performed for natural and wind excited *** numerical model was made using the Spectral Element *** the spectral model,for various parameters of stiffness,damping and tension force,the system response was checked and compared with the results of the accelerations obtained in the situ measurements.A frequency response functions(FRF)were *** credibility of the model was assessed through a validation process carried out by comparing graphical plots of FRF functions and numerical values expressing differences in acceleration amplitude(MSG),phase angle differences(PSG)and differences in acceleration and phase angle total(CSG)*** attention was paid to the hysteretic damping *** of the wave number was performed for changing of the tension force and section area of the *** next aspect constituting the purpose of this paper was to present the wide possibilities of modelling and simulation of slender conductors using the Spectral Element *** obtained results show very good accuracy in the range of both experimental measurements as well as simulation *** paper emphasizes the ease with which the sensitivity of the conductor and its response to changes in density of spectral mesh division,cable cross-section,tensile strength or material damping can be studied.

关键词： Transmission line Spectral Element Method frequency response function

Characteristics of 100Cr6 bearing steel after thixoforming process performed with prototype device

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中国有色金属学会会刊：英文版 2010年第S3期20卷 1033-1036页

作者： L.ROGAL J.dutkiewicz T.CZEPPE J.BONARSKI B.OLSZOWSKA-SOBIERAJ Institute of Metallurgy and Materials Science of the Polish Academy of Sciences 30-059 Kraków25 Reymonta St.Poland Faculty of Foundry Engineering University of Science and Technology30-059 Kraków23 Reymonta St.Poland

A device based on a high pressure die-casting(HPDC) machine was constructed,with a capacity to produce thixo-casts from *** inductive heating to the required semi-solid temperature range,the samples were transported in a protective argon atmosphere to a cylinder of modified HPDC and injected into a pre-heated *** steel 100Cr6(after forging) was used as the feedstock *** metallographic analysis of the steel showed a homogenous structure within a whole volume characterized by a grain size between 2 μm and 8 μ*** scanning calorimetry(DSC) analysis allowed to estimate the process temperature for thixoforming at 1 390 ?C which was attributed to about 45% of a liquid *** such technological parameters after the semi-solid processing the microstructure consisted of globular grains of size from 15 μm to 40 μ*** microstructure of globules indicated predominant presence of martensite(about 76% volume fraction) with residual austenite between plates.X-ray analysis confirmed that the thixo-cast samples contain mainly martensite and residual *** hardness of the initial forged sample was HRC 27 and after the thixoforming process it was HRC 60,which confirms the presence of martensite and *** thixo-casts were subjected to low tempering,at temperature of 150 °C for a period of 2 h,in order to remove stresses created during the process of thixoforming and to increase *** hardness after tempering was HRC ***,in order to identify phases present in the thixo-casts,transmission electron microscopy(TEM) was carried out.

关键词： SSM semi-solid metal thixoforming 100Cr6 steel

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异构网络中多模终端业务流分发技术研究

计算机学报 2010年第6期33卷 1004-1013页

作者：孙毅葛雨明 HERBORN Stephen dutkiewicz Eryk 中国科学院计算技术研究所北京100190 澳大利亚国家信息通信技术研究中心NSW1430澳大利亚麦考瑞大学NSW2109澳大利亚

伴随着异构网络的迅猛发展,多模终端日益普及.当终端上有多种不同类型的会话业务流需要传输时,如何根据不同类型业务流的特点、不同网络的当前链路状况、通信费用、传输功耗等因素,在终端所接入的多个网络之间自动地、合理地分发业务流... 详细信息

伴随着异构网络的迅猛发展,多模终端日益普及.当终端上有多种不同类型的会话业务流需要传输时,如何根据不同类型业务流的特点、不同网络的当前链路状况、通信费用、传输功耗等因素,在终端所接入的多个网络之间自动地、合理地分发业务流就成为一个非常重要的问题.文中提出了一套针对多模终端业务流分发问题的解决方案,包括支持业务流自动分发的多模终端框架结构及其包含的业务流分发算法.方案引入优先级的概念使得高等级的业务流在网络负载较重时具有使用网络的优先权,同时方案包含了一种权重自生成方法,为影响业务流分发决策的多个属性自动生成权重,减轻了用户负担,避免了由用户直接指定权重的困难.仿真实验的结果表明,文中方案能够根据当前各接入网络的链路状况、不同类型业务流的服务质量需求、传输功耗、通信成本等多个属性,自动为多模终端上运行的各条业务流选择合理的接入网络,同时方案在吞吐量、会话完成率等性能指标上也拥有显著改进.

关键词：业务流分发异构网络多模终端

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基于调度集合的多播单播数据联合调度算法

软件学报 2008年第12期19卷 3196-3206页

作者：田霖杨育波方更法石晶林 dutkiewicz Eryk 中国科学院计算技术研究所下一代互联网研究中心北京100190 Wireless Technologies Laboratory University of Wollongong of Australia Australia 中国科学院研究生院北京100049

首先定义和分析了IEEE802.16e无线城域网中的一个新问题,即如何在保证移动终端服务质量的前提下,通过合理地调度终端的单播业务和多播业务来降低终端能耗.针对该问题,提出一种基于调度集合的联合调度算法(scheduling set based integrat... 详细信息

首先定义和分析了IEEE802.16e无线城域网中的一个新问题,即如何在保证移动终端服务质量的前提下,通过合理地调度终端的单播业务和多播业务来降低终端能耗.针对该问题,提出一种基于调度集合的联合调度算法(scheduling set based integrated scheduling,简称SSBIS).SSBIS算法将所有移动终端划分到多播调度集合或单播调度集合中,并利用多播数据的传输特点,在多播数据传输的相邻时隙内发送多播调度集合中所有终端的单播数据,而对于单播调度集合中的终端,则通过凸优化方法求得使终端休眠时间最长的单播业务调度方案,以达到降低终端能耗的目的.仿真实验显示,SSBIS算法在满足移动终端的最小数据速率要求的同时,可以明显地降低终端能耗.

关键词： IEEE 802.16e 省电联合调度多播调度集合

RSVP协议在移动IPv6网络中的扩展性研究

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软件学报 2008年第7期19卷 1731-1742页

作者：孙毅张玉成冯斌方更法石晶林 dutkiewicz Eryk 中国科学院计算技术研究所北京100190 中国科学院研究生院北京100049 电子科技大学四川成都610054 北京邮电大学北京100876 University of Wollongong of Australia NSW 2522Australia

针对无线移动通信的特点,提出了一种在移动IPv6网络中保障用户通信服务质量的资源预留新方案Fast RSVP.该方案采用跨层设计的思想,将两个不同层次的模块:移动IPv6模块和RSVP模块结合起来,通过在两个模块之间增加一些原语使得二者配合工... 详细信息

针对无线移动通信的特点,提出了一种在移动IPv6网络中保障用户通信服务质量的资源预留新方案Fast RSVP.该方案采用跨层设计的思想,将两个不同层次的模块:移动IPv6模块和RSVP模块结合起来,通过在两个模块之间增加一些原语使得二者配合工作以保证移动用户的通信业务质量.Fast RSVP方案引入了邻居隧道提前资源预留、优化路径资源预留、切换预留、路径融合等一系列新机制.仿真实验结果表明,与其他移动环境中的RSVP扩展方案相比,该Fast RSVP方案在支持无线移动通信方面具有如下优势:(1)能够实现移动节点带有服务质量保证的快速切换;(2)能够避免移动IP切换过程中三角路由和重复预留造成的资源浪费;(3)能够区分不同类型的切换预留请求,在保证网络整体性能的前提下显著降低因为切换而导致的服务中断率.

关键词：资源预留移动IPv6 服务质量跨层多媒体

Raman Microspectroscopy as a Unique Method of the Investigation of Acid Proof Steel Foil Oxidation

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Optics and Photonics Journal 2013年第5期3卷 7-12页

作者： A.Weselucha-Birczyńska J.dutkiewicz E.Bielańska L.Lityńska-Dobrzyńska M.Kozicki W.Lasocha A.Rafalska-Lasocha M.Najbar Faculty of Chemistry Jagiellonian UniversityKrakówPoland Jerzy Haber Institute of Catalysis and Surface Chemistry Polish Academy of SciencesKrakówPoland Institute of Metallurgy and Materials Science Polish Academy of Sciences CracowPoland

In this paper, the results of the investigation of the morphology and phase composition of the oxide layers formed on the surface of the 1H18N9T acid proof steel foil by confocal Raman micro-spectroscopy with optical microscopy, SEM, XRD and TEM-EDS-SADP are presented. The foil oxidation was performed by thermo-programmed heating up to 823, 1023 or 1113 K and next annealing at the final temperatures in the air flow for 48 h, 4 h and 4 h, respectively. The great advantages of the use of the Raman spectroscopy for the phase determining in the oxide layers on the acid proof steel foil are shown. Moreover the possibility of applying the optical microscopy for investigation of the surface morphology of both the initial steel foil and the oxide layers is pointed out.

关键词： 1H18N9T Steel Foil Oxidation Raman Microspectroscopy Morphology Phases

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新冠大流行与世界秩序

俄罗斯研究 2020年第5期 50-69页

作者：叶莲娜·切班科娃彼得·杜特科维奇杨辉(翻译) 加拿大卡尔顿大学政府与公共管理中心潍坊医学院外国语学院

本文主要探讨由新冠大流行所引发的此次全球性危机的起源、性质及潜在的后果。在过去60年里,全球危机是世界经济和政治体系中两大精英派别(全球金融资本代表和地区主义工业家代表)之间各种矛盾不断累积的结果,而当前这场疫情又使既有危... 详细信息

本文主要探讨由新冠大流行所引发的此次全球性危机的起源、性质及潜在的后果。在过去60年里,全球危机是世界经济和政治体系中两大精英派别(全球金融资本代表和地区主义工业家代表)之间各种矛盾不断累积的结果,而当前这场疫情又使既有危机加深和激化。首先,新冠危机的发展态势,充分显露了当代资本主义制度借助制造道德恐慌①和操纵媒体这两种手段来实现自身合法性的本质特征。每次持续性的资本主义危机,都是在不同利益群体中以权力资源的重新分配而告终。其次,全球两大精英派别对世界秩序的变化持有截然不同的立场,在政治和经济上的具体目标和意图也各不相同。正是在这样相互对立的背景下,爆发了此次危机。这场危机不会根本性地改变世界,但会激化两大精英集团之间的紧张关系,并暴露在众多普通人眼前,从而加深业已存在的、系统性的不稳定。

关键词：全球危机新冠疫情全球金融资本世界秩序资本主义制度