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The microstructural evolution in Ni-base superalloy powders under controllable fast heating condition

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The microstructural evolution in Ni-base superalloy powders ...

第二届海峡两岸功能材料科技与产业峰会（2015）

作者： Liang Zheng Guoqing Zhang T.L.Lee M.j.Gorley Na Liu Z.Hong S.Day c.c.Tang D. Daisenberger Zhou Li j.Mi P.S.Grant Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials School of Engineering University of Hull Department of Materials University of OxfordBegbroke Science Park

Spray forming have been employed for manufacturing superalloy components recent years[1-4].One of the fundamental issues that is still debating actively is how the droplets/powders with dendritic structure(Fig.1a,c)transformed into equiaxed fine grains(Fig.1b,d)in the consolidated *** and vivid experimental evidence is still very difficult to obtain due to its very harsh,high dynamic and high temperature ***

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串联电容补偿线路的相差保护特性研究

电网技术 2007年第13期31卷 86-90页

作者：温荣谭建成广西大学电气工程学院广西壮族自治区南宁市530004

高压输电线路上靠近串补电容处发生故障时,由于电容的补偿作用,线路两端电流、电压的相位差可能达到180°,远远超出了传统相差保护的整定值,导致保护无法判别故障。为此,作者提出一种改进算法,对故障时的暂态电流信号进行小波变换,获取... 详细信息

高压输电线路上靠近串补电容处发生故障时,由于电容的补偿作用,线路两端电流、电压的相位差可能达到180°,远远超出了传统相差保护的整定值,导致保护无法判别故障。为此,作者提出一种改进算法,对故障时的暂态电流信号进行小波变换,获取暂态相位差值作为保护动作的依据,并考虑了金属氧化物变阻器不能导通时串补电容对保护性能的影响。仿真结果表明,改进算法能快速准确地判断故障区域,弥补了传统保护的缺陷,且不受串补电容补偿度、安装地点的影响,对普通线路同样适用。

关键词：串补线路金属氧化物变阻器(MOV) 相差保护实时数字仿真(RTDS) 小波变换继电保护

Adaptive green traffic signal controlling using vehicular communication

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Frontiers of Information Technology & Electronic Engineering 2017年第3期18卷 373-393页

作者： Erfan SHAGHAGHI Mohammad Reza jABBARPOUR Rafidah MD NOOR Hwasoo YEO jason j.jUNG Department of computer Systems and Technology University of Malaya Department of computer Engineering Islamic Azad UniversityNorth Tehran Branch Department of civil and Environmental Engineering Korea Advanced Institute of Science and Technology Department of computer Engineering Chung-Ang University

The importance of using adaptive traffic signal control for figuring out the unpredictable traffic congestion in today's metropolitan life cannot be overemphasized. The vehicular ad hoc network(VANET), as an integral component of intelligent transportation systems(ITSs), is a new potent technology that has recently gained the attention of academics to replace traditional instruments for providing information for adaptive traffic signal controlling systems(TScSs). Meanwhile, the suggestions of VANET-based TScS approaches have some weaknesses:(1) imperfect compatibility of signal timing algorithms with the obtained VANET-based data types, and(2) inefficient process of gathering and transmitting vehicle density information from the perspective of network quality of service(Qo S). This paper proposes an approach that reduces the aforementioned problems and improves the performance of TScS by decreasing the vehicle waiting time, and subsequently their pollutant emissions at intersections. To achieve these goals, a combination of vehicle-to-vehicle(V2V) and vehicle-to-infrastructure(V2I) communications is used. The V2 V communication scheme incorporates the procedure of density calculation of vehicles in clusters, and V2 I communication is employed to transfer the computed density information and prioritized movements information to the road side traffic controller. The main traffic input for applying traffic assessment in this approach is the queue length of vehicle clusters at the intersections. The proposed approach is compared with one of the popular VANET-based related approaches called Mc-DRIVE in addition to the traditional simple adaptive TScS that uses the Webster method. The evaluation results show the superiority of the proposed approach based on both traffic and network Qo S criteria.

关键词： Vehicular ad hoc network(VANET) Intelligent transportation systems(ITSs) clustering Adaptive traffic signal control Traffic controller Fuel consumption

Symmetry-aware recursive image similarity exploration for materials microscopy

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npj computational Materials 2021年第1期7卷 1508-1521页

作者： Tri N.M.Nguyen Yichen Guo Shuyu Qin Kylie S.Frew Ruijuan Xu joshua c.Agar Department of Materials Science and Engineering Lehigh UniversityBethlehemPA 18015USA Department of computer Science and Engineering Lehigh UniversityBethlehemPA 18015USA Department of Mechanical Engineering Lehigh UniversityBethlehemPA 18015USA Department of Applied Physics Stanford UniversityStanfordCA 94305USA

In pursuit of scientific discovery,vast collections of unstructured structural and functional images are acquired;however,only an infinitesimally small fraction of this data is rigorously analyzed,with an even smaller fraction ever being *** method to accelerate scientific discovery is to extract more insight from costly scientific experiments already ***,data from scientific experiments tend only to be accessible by the originator who knows the experiments and ***,there are no robust methods to search unstructured databases of images to deduce correlations and ***,we develop a machine learning approach to create image similarity projections to search unstructured image *** improve these projections,we develop and train a model to include symmetry-aware *** an exemplar,we use a set of 25,133 piezoresponse force microscopy images collected on diverse materials systems over five *** demonstrate how this tool can be used for interactive recursive image searching and exploration,highlighting structural similarities at various length *** tool justifies continued investment in federated scientific databases with standardized metadata schemas where the combination of filtering and recursive interactive searching can uncover synthesis-structure-property *** provide a customizable open-source package(https://***/m3-learning/Recursive_Symmetry_Aware_Materials_Microstructure_Explorer)of this interactive tool for researchers to use with their data.

关键词： interactive image similarity

Net primary productivity and its control of the Middle jurassic peatlands: An example from the southern junggar coalfield

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Science china Earth Sciences 2018年第11期61卷 1633-1643页

作者： Yanan LI Longyi SHAO Zhiming YAN Haihai HOU Yue TANG David j.LARGE college of Geoscience and Surveying Engineering China University of Mining and Technology Oil and Gas Resources Survey center China Geological Survey Administration Faculty of Engineering University of Nottingham

The jurassic is an important period of global coal formation, including the development of several large coalfields in central Asia and northern china. Individual seams within these peatlands represent sustained periods of terrestrial carbon accumulation and a key environmental indicator attributed to this record is the rate of carbon accumulation. Determining the rate of carbon accumulation requires a measure of time contained within the coal and this study aimed at determining the rate via the identification of Milankovitch orbital cycles using spectral analysis. Spectral analyses of geophysical data from two thick coal seams, No. 43(35.9 m) and No. 3(13.2 m), of the Middle jurassic of the southern junggar coalfield were conducted to identify significant signals of variations in ash content. The results showed that the variations in ash content of the coal showed spatial cycles at 0.2, 0.7 and 1.1 m^(-1), which were interpreted to represent 123 ka(eccentricity), 37.1 ka(obliquity), and 21.2 ka(precession) orbital periodicities, respectively. Using this timeframe, the depositional time of the No. 43 and No. 3 coal seams were calculated to be 876–970 and 322–357 ka, respectively. In combination with an understanding of carbon loss during coalification, the carbon accumulation rates of these Middle jurassic peatlands were calculated to be 58.6–64.9 and60.3–66.8 g c m^(-2) a^(-1) for the No. 43 and No. 3 coal seams, respectively. Given that the net primary productivity(NPP) was 4.3 times the value of the carbon accumulation in a mid-latitude region of 40°–45°N, an NPP of 251.8–279.1 and259.1–287.1 g c m^(-2) a^(-1) was calculated for the No. 43 and No. 3 coal seams, respectively. In the context of the same paleolatitude(40°–45°N) and peat type, the NPP values of the Middle jurassic strata in the study area were higher than those of the peatlands of the Holocene and Permian, and were similar to the NPP values of Early cretaceous peatlands. considering the NPP of a peat

关键词： Peatland Middle jurassic Milankovitch cycle Net primary productivity Mid-latitude region Paleoclimate

Phosphogypsum stabilization of bauxite residue:conversion of its alkaline characteristics

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journal of Environmental Sciences 2019年第3期31卷 1-10页

作者： Shengguo Xue Meng Li jun jiang Graeme j.Millar chuxuan Li Xiangfeng Kong School of Metallurgy and Environment Central South University Institute for Future Environments Science and Engineering Faculty Queensland University of Technology

Reduction of the high alkalinity of bauxite residue is a key problem to solve to make it suitable for plant growth and comprehensive utilization. In this study, phosphogypsum, a waste product from the phosphate fertilizer industry, was used to drive the alkaline transformation of the bauxite residue. Under optimal water washing conditions(liquid/solid ratio of 2 mL/g, 30°c, 24 hr), the impact of quantity added, reaction time and reaction mechanism during phosphogypsum application were investigated. Phosphogypsum addition effectively lowered p H levels and reduced the soluble alkalinity by 92.2%. It was found that the concentration of soluble Na and ca ions in the supernatant increased gradually, whilst the exchangeable Na+and ca^(2+)in solid phase changed 112 mg/kg and 259 mg/kg, respectively. ca^(2+)became the dominant element in the solid phase(phosphogypsum addition of 2%, liquid/solid ratio of 2 mL/g, 30°c, 12 hr). X-ray diffraction data indicated that cancrinite and hydrogarnet were the primary alkaline minerals. SEM images suggested that phosphogypsum could promote the formation of stable macroaggregates, whilst the content of ca^(2+)increased from 5.6% to 18.2% and Na reduced from 6.8% to 2.4%. Treatment with phosphogypsum could significantly promote the transformation of alkalinity cations by neutralization, precipitation and replacement *** research provided a feasible method to promote soil formation of bauxite residue by phosphogypsum amendment.

关键词： Bauxite residue Phosphogypsum Alkaline ions Alkaline transformation Soil formation

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电子网络中的知识概念

ON APPROXIMATION OF A FUNcTION AND ITS DERIVATIVES BY A POLYNOMIAL AND ITS DERIVATIVES

科学技术哲学 1999年第9期 30-39页

作者： j.c.尼弗里编

在写作现在这一总结时（1997年1月），我们对网络认识论的了解比两年前这一合作主题确定下来时多得多了。这种增长部分地是由于网络本身的巨大发展；然而，部分地是我们自己所进行的一系列交流所造成的。因此，我宁愿说这一课题产生了...

在写作现在这一总结时（1997年1月），我们对网络认识论的了解比两年前这一合作主题确定下来时多得多了。这种增长部分地是由于网络本身的巨大发展；然而，部分地是我们自己所进行的一系列交流所造成的。因此，我宁愿说这一课题产生了积极的成果；但是这可能会产生误导。首先，因为在概念用语上我们的结果主要是否定的，因而容易产生误导。关于如何不在网上强调知识问题，以及关于这一难题不是什么，我们已经有了重要的结果。但是，我们没有成功地发现新的肯定性概念。而且我认为我现在知道在这里我们从一开始就注定要失败。其次，从电子讨论尚未真正出现的意义上讲，这种结果是消极的。这就是我使用“一系列交流”这一迂回说法的理由。当然，我们使用了电子邮件和邮件表；当然，其中的文本是数字化形式，并可在同时获得。但是，我起初提出的讨论话题（一个传统的哲学话题）根本不适合在网络环境中讨论。无疑，哲学在网上具有自己存在的空间——或者我们应当称之为时间（？）。网络确实需要它的哲学家。但是这些哲学家以及他们的问题所属的世界完全不同于我们所知道的哲学世界。我认为，这就是我们从这一课题中所得到的主要教训。下面是它如何开始的，即在1996 年1 月，我用电子邮件给“ mii—cken”目录发去一个文本：亲爱的网友：我们的讨论（像“一元论者人机对话问题”所面临的所有其他讨论一样）应当以主持人邮出通常称为“目标论文”的活动开始，这已是大家的共识。主持人（即我）早在很久以前就应当完成这一点——事实上是在去年十月底完成的。如今我担心，现在这一文本仍然不是你们所期望的论文。或许根本没有这一论文——或许这一讨论从一开始就必须出现。其理由是：随着时间的推移，我发现越来越难于坚持我在过去几年间所坚持的观点——然而，却没有达到某种确定的、可选择的立场。尤其是我在1994年所撰写的《电子网络和知识的统一》一文中所捍卫的观点，已经不再令我满意了。我逐渐感到那些观点的印刷偏见对我有干扰——尤其是在阅读了塔尔博特（Talbott）的《未来不能计算》以后，更是如此。塔尔博特对于有意义的知识意味着什么具有某种陈腐观念；他的哲学人类学完全是非历史的；这种非历史性使得我在自己先前的研究中，以我现在认为是潜在的非历史态度看待问题。我并不是说《电子网络和知识的统一》中所有观点都是错误的（其实，如果你们中有人在某些阶段想看上它一眼，我将感到欣慰——我将把这一论文与这一文本一起用电子邮件给诸位寄去）；但是它的论证预先假定了某些观念具有永恒的有效性，而事实上，据我现在所知，这些观念是受印刷书籍的年限所制约的。

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Analysis in Theory and Applications 1994年第3期10卷 93-103页

作者： T.Kilgore j.Szabados Aubunn University U.S.A Mathematical Institute of the Hungarian of Academy of Sciences. Hungaria

Let g∈c^q[-1, 1] be such that g^((k))(±1)=0 for k=0,…,q. Let P_n be an algebraic polynomial of degree at most n, such that P_n^((k))(±1)=0 for k=0,…,[_2~ (q+1)]. Then P_n and its derivatives P_n^((k)) for k≤q well approximate g and its respective derivatives, provided only that P_n well approxi- mates g itself in the weighted norm ‖g(x)-P_n(x) (1-x^2)^(1/2)~q‖ This result is easily extended to an arbitrary f∈c^q[-1, 1], by subtracting from f the polynomial of minnimal degree which interpolates f^((0))…,f^((q)) at±1. As well as providing easy criteria for judging the simultaneous approximation properties of a given Polynomial to a given function, our results further explain the similarities and differences between algebraic polynomial approximation in c^q[-1, 1] and trigonometric polynomial approximation in the space of q times differentiable 2π-periodic functions. Our proofs are elementary and basic in character, permitting the construction of actual error estimates for simultaneous approximation proedures for small values of q.

关键词： ON APPROXIMATION OF A FUNcTION AND ITS DERIVATIVES BY A POLYNOMIAL AND ITS DERIVATIVES ITS

cENTRAL cORNEAL THIcKNESS IN WHITE AND YELLOW PATIENTS IN BRAZIL

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国际眼科杂志 2003年第1期3卷 63-64页

作者： M.Hatanaka j.A.Ferreira P.A.Florencia c.Morita R.Susanna-jr. Hospital Das clinicas da Faculdade de Medicina da USP BrazilHospital Das Clinicas da Faculdade de Medicina da USP BrazilHospital Das Clinicas da Faculdade de Medicina da USP BrazilHospital Das Clinicas da Faculdade de Medicina da USP BrazilHospital Das Clinicas da Faculdade de Medicina da USP Brazil

Purpose: To determine if there is a difference in central corneal thickness (ccT) of white and yellow Brazilian patients. Methods: We retrospectively compared the ccT data of yellow patients living in Brazil and white Brazilian patients. ccT was measured with an ultrasound pachymeter (compuscan P Ultrasonic Pachymeter System model UPc 1000 ). One eye of each patient was randomly selected for statistical analysis. A two sample t

关键词：巴西白人患者黄种人患者角膜中央厚度