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程序升温还原技术对Cu-Al尖晶石材料的表征识别 被引量:1
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作者 刘雅杰 张文月 +2 位作者 边文璐 康荷菲 冯军鹏 《化学研究与应用》 CAS CSCD 北大核心 2022年第2期391-398,共8页
通过机械球磨和固相焙烧的方法合成了组成不同的纳米铜铝尖晶石材料,采用X射线粉末衍射、高分辨透射电镜和程序升温还原技术(H_(2)-TPR)对其进行了表征,结果发现:基于H_(2)-TPR技术能够表征识别Cu-Al尖晶石固溶体与计量CuAl_(2)O_(4)尖... 通过机械球磨和固相焙烧的方法合成了组成不同的纳米铜铝尖晶石材料,采用X射线粉末衍射、高分辨透射电镜和程序升温还原技术(H_(2)-TPR)对其进行了表征,结果发现:基于H_(2)-TPR技术能够表征识别Cu-Al尖晶石固溶体与计量CuAl_(2)O_(4)尖晶石,并可得出合成样品中Cu-Al尖晶石晶相的分子式。H_(2)-TPR分析条件的研究表明:称样质量、气体流速、升温速率和热导电流等对还原峰温度和强度有明显的影响,但样品中不同铜物种的相对含量保持基本不变,证明了基于H_(2)-TPR技术表征识别Cu-Al尖晶石的可靠性和合理性。对一定组成的Cu-Al尖晶石样品,适宜的H_(2)-TPR分析条件应综合考虑称样质量、气体流速、升温速率和热导电流。 展开更多
关键词 铜铝尖晶石 程序升温还原 表征识别 分析条件
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自动矿物识别和表征系统在辽东吉祥峪稀土矿矿物鉴定和赋存状态研究中的应用 被引量:2
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作者 孙晓旭 冯坚 +5 位作者 李超 高野 王雷 苗彤 徐杨 闫伟 《岩矿测试》 CAS CSCD 北大核心 2023年第6期1120-1131,共12页
辽宁省已知的稀土矿类型较少,以往稀土矿床的勘查评价偏重于独居石砂矿和碱性岩型稀土矿,沉积变质型稀土矿涉及较少,其矿石学、矿物学研究程度偏低。本文以吉祥峪稀土矿床为研究对象,应用自动矿物识别和表征系统(AMICS),结合高分辨率扫... 辽宁省已知的稀土矿类型较少,以往稀土矿床的勘查评价偏重于独居石砂矿和碱性岩型稀土矿,沉积变质型稀土矿涉及较少,其矿石学、矿物学研究程度偏低。本文以吉祥峪稀土矿床为研究对象,应用自动矿物识别和表征系统(AMICS),结合高分辨率扫描电子显微镜(SEM)和高通量能谱仪(EDS)对矿石进行分析,获得吉祥峪稀土矿石中矿物化学成分、元素赋存状态及矿物共生组合关系。结果表明,矿石中稀土元素以La、Ce、Pr、Nd等轻稀土元素为主;主要稀土矿物为独居石(0.73%)、褐帘石(6.25%)、方铈石(0.25%)和磷灰石(类质同象)等;通过背散射图像结合光学显微镜观察得出矿石中的褐帘石、独居石、方铈石及磷灰石等具有较好的连生关系,这些矿物以单颗粒或聚粒结构与磁铁矿交叉镶嵌,或分布在磁铁矿边缘及间隙中。矿石中稀土矿物与磁铁矿密切共生,含量呈正相关,其原因可能为:①沉积富集。吉祥峪稀土矿位于辽吉裂谷的核部,裂谷为矿床提供了有利的沉积环境。②岩浆改造。岩浆热液可能与里尔峪一段变粒岩产生反应,使其中的稀土和铁元素集聚。③构造控制。吉祥峪稀土矿位于吉祥峪—算盘峪背斜核部穹隆之上,构造发育,断裂带和褶皱可能在地壳的应力作用下形成矿物质富集的通道,使矿质从深部运移至浅部。 展开更多
关键词 自动矿物识别表征系统(AMICS) 沉积变质型稀土矿 独居石 褐帘石 磁铁矿 稀土矿物赋存状态
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小行星形貌测绘与表征技术 被引量:2
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作者 徐青 王栋 +1 位作者 邢帅 蓝朝桢 《深空探测学报》 2016年第4期356-362,共7页
小行星表面形貌测绘是深空小行星探测的首要任务。提出了一种适应探测器抵近观测的立体视觉在线测绘小行星形貌的方法,即先由立体相机获得所摄重叠区的三维地形,再用前后立体模型的连接点将各个独立模型连成一个完整地形信息,经整体最... 小行星表面形貌测绘是深空小行星探测的首要任务。提出了一种适应探测器抵近观测的立体视觉在线测绘小行星形貌的方法,即先由立体相机获得所摄重叠区的三维地形,再用前后立体模型的连接点将各个独立模型连成一个完整地形信息,经整体最小二乘平差,确定小行星的形貌模型及特征;同时提出了一种基于等值线分析的撞击坑特征提取方法,即通过提取、分析地形等值线识别出地形中撞击坑特征。实验结果显示,本文所构建的原型系统能够快速重建出探测区域的三维地形,并识别出地形中撞击坑特征,证明了所提方法具有实用性。 展开更多
关键词 小行星 形貌测绘 立体视觉 撞击坑 表征识别
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塔里木盆地顺北地区海相超深碳酸盐岩油气勘探物探技术需求与创新应用 被引量:10
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作者 漆立新 《石油物探》 CSCD 北大核心 2023年第3期381-394,共14页
塔里木盆地顺北地区海相超深层碳酸盐岩是塔里木盆地油气勘探的重点领域之一。经过地震采集、处理成像、量化识别和地质工程一体化解释的系统攻关,逐渐形成了高密度、高精度、面向缝洞体的三维地震采集技术;宽频带、高保真全波场地震处... 塔里木盆地顺北地区海相超深层碳酸盐岩是塔里木盆地油气勘探的重点领域之一。经过地震采集、处理成像、量化识别和地质工程一体化解释的系统攻关,逐渐形成了高密度、高精度、面向缝洞体的三维地震采集技术;宽频带、高保真全波场地震处理技术;叠前宽方位分析、各向异性检测、可视化等多维度解释技术。但作为典型的非层状油气藏,塔里木盆地顺北地区海相超深碳酸盐岩油气地震勘探理论与地震勘探实践仍面临全方位的挑战,未来应进一步加强物探技术攻关,包括进一步完善地震散射波传播与成像理论;试验以“共中心点离散化、近偏高覆盖、多观测系统”为主的地震采集技术;重新认识噪声,实现多态式地震波处理和全波场地震成像;积极探索智能化解释技术,综合岩石物理分析与正演模拟、多态式的叠前反演与地震属性分析,精细描述缝洞体及其内幕。这些技术对支撑顺北地区持续重大突破和持续发展,以及对国内外超深层碳酸盐岩勘探和非层状油气藏勘探具有借鉴意义。 展开更多
关键词 超深碳酸盐岩油气藏 断控缝洞体 非层状油气藏勘探 地震波场 散射波地震采集 多态式地震处理成像 地震散射波识别和量化表征
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致密储层研究进展和热点问题分析 被引量:79
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作者 朱筱敏 潘荣 +2 位作者 朱世发 魏巍 叶蕾 《地学前缘》 EI CAS CSCD 北大核心 2018年第2期141-146,共6页
全球常规油气及非常规油气资源极为丰富,其中致密油气是非常规油气资源的主要类型,是当前非常规油气勘探的重点,也是未来接替常规油气资源的重要领域。致密储层具有油气资源量大、分布面积广、成岩作用强、单井产量较低、储层非均质性... 全球常规油气及非常规油气资源极为丰富,其中致密油气是非常规油气资源的主要类型,是当前非常规油气勘探的重点,也是未来接替常规油气资源的重要领域。致密储层具有油气资源量大、分布面积广、成岩作用强、单井产量较低、储层非均质性强等特点。在富含油气资源的致密储层中,具有良好物性的"甜点"是提高产量的有利勘探目标,其"甜点"主要包括两类,一类为异常高孔带,另一类为裂缝发育带。目前,致密储层的研究现状主要包括致密储层划分、地质特征、形成机理和有利储层预测等。近年来,"甜点"的形成机理和预测成为当前致密储层勘探开发的重要科学问题。因此,致密储层微观孔喉结构表征、致密储层裂缝发育识别表征是目前致密储层研究的热点领域及未来主要发展方向。 展开更多
关键词 致密储层 甜点 形成机理 微观孔喉结构表征 裂缝发育识别表征
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如何定义绩效管理中的“完成”:在不确定性中寻找确定性 被引量:1
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作者 杜哲 《技术与市场》 2022年第5期166-168,共3页
绩效管理是实现公司战略的重要环节,是一项衡量、评价、影响员工工作表现的复杂的系统工程。如何定义绩效管理中的“完成”,是实现绩效管理作用的关键一环。对绩效指标进行分类,并对每类指标的“灰度”进行表征与原因分析,针对性地提出... 绩效管理是实现公司战略的重要环节,是一项衡量、评价、影响员工工作表现的复杂的系统工程。如何定义绩效管理中的“完成”,是实现绩效管理作用的关键一环。对绩效指标进行分类,并对每类指标的“灰度”进行表征与原因分析,针对性地提出应对措施,作出前景展望,旨在减少绩效管理过程和结果中的不确定性,充分发挥其承上启下的作用,从而实现企业战略目标。 展开更多
关键词 绩效管理 表征识别 风险与问题 应对措施
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AN ADAPTIVELY TRAINED KERNEL-BASED NONLINEAR REPRESENTOR FOR HANDWRITTEN DIGIT CLASSIFICATION 被引量:12
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作者 Liu Benyong Zhang Jing 《Journal of Electronics(China)》 2006年第3期379-383,共5页
In practice, retraining a trained classifier is necessary when novel data become available. This paper adopts an incremental learning procedure to adaptively train a Kernel-based Nonlinear Representor (KNR), a recentl... In practice, retraining a trained classifier is necessary when novel data become available. This paper adopts an incremental learning procedure to adaptively train a Kernel-based Nonlinear Representor (KNR), a recently presented nonlinear classifier for optimal pattern representation, so that its generalization ability may be evaluated in time-variant situation and a sparser representation is obtained for computationally intensive tasks. The addressed techniques are applied to handwritten digit classification to illustrate the feasibility for pattern recognition. 展开更多
关键词 Pattern recognition Handwritten digit recognition Incremental learning Sparse representation Kernel-based Nonlinear Representor (KNR)
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A flower image retrieval method based on ROI feature 被引量:6
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作者 洪安祥 陈刚 +2 位作者 李均利 池哲儒 张亶 《Journal of Zhejiang University Science》 CSCD 2004年第7期764-772,共9页
Flower image retrieval is a very important step for computer-aided plant species recognition. In this paper, we propose an efficient segmentation method based on color clustering and domain knowledge to extract flower... Flower image retrieval is a very important step for computer-aided plant species recognition. In this paper, we propose an efficient segmentation method based on color clustering and domain knowledge to extract flower regions from flower images. For flower retrieval, we use the color histogram of a flower region to characterize the color features of flower and two shape-based features sets, Centroid-Contour Distance (CCD) and Angle Code Histogram (ACH), to characterize the shape features of a flower contour. Experimental results showed that our flower region extraction method based on color clustering and domain knowledge can produce accurate flower regions. Flower retrieval results on a database of 885 flower images collected from 14 plant species showed that our Region-of-Interest (ROI) based retrieval approach using both color and shape features can perform better than a method based on the global color histogram proposed by Swain and Ballard (1991) and a method based on domain knowledge-driven segmentation and color names proposed by Das et al.(1999). 展开更多
关键词 Flower image retrieval Knowledge-driven segmentation Flower image characterization Region-of-Interest (ROI) Color features Shape features
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Towards a cure for HIV: the identification and characterization of HIV reservoirs in optimally treated people
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作者 Adewunmi Onafuwa-Nugal Lucy A McNamara Kathleen L Collins 《Cell Research》 SCIE CAS CSCD 2010年第11期1185-1187,共3页
Currently available anti-HIV-1 drugs suppress viral replication and maintain viral levels below the detection threshold of most assays but do not eliminate cellular reservoirs. As a result, very low levels of circulat... Currently available anti-HIV-1 drugs suppress viral replication and maintain viral levels below the detection threshold of most assays but do not eliminate cellular reservoirs. As a result, very low levels of circulating virus can be detected in most people despite long-term treatment with potent anti-HIV drug combinations. Not surprisingly, viral levels rebound with discontinuation of treatment. New evidence indicates that there is a viral reservoir in bone marrow progenitor cells. 展开更多
关键词 HIV LATENCY bone marrow stem cells CD34
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Wear Debris Identification Using Feature Extraction and Neural Network
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作者 王伟华 马艳艳 +1 位作者 殷勇辉 王成焘 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期42-45,共4页
A method and results of identification of wear debris using their morphological features are presented. The color images of wear debris were used as initial data. Each particle was characterized by a set of numerical ... A method and results of identification of wear debris using their morphological features are presented. The color images of wear debris were used as initial data. Each particle was characterized by a set of numerical parameters combined by its shape, color and surface texture features through a computer vision system. Those features were used as input vector of artificial neural network for wear debris identification. A radius basis function (RBF) network based model suitable for wear debris recognition was established, and its algorithm was presented in detail. Compared with traditional recognition methods, the RBF network model is faster in convergence, and higher in accuracy. 展开更多
关键词 wear debris CHARACTERIZATION neural network pattern recognition.
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白石湖煤加氢液化过程含氮化合物转化行为研究
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作者 刘敏 陈贵锋 +3 位作者 赵鹏 赵天博 史权 王吉坤 《煤质技术》 2021年第6期36-43,共8页
对煤加氢液化过程中含氮化合物的转化行为及在气、液、固三相产物中的赋存形态进行研究,可为低阶煤的高效洁净利用奠定理论基础。在0.01 t/d连续试验装置完成新疆白石湖煤加氢液化连续试验,采用微量硫氮分析仪、氮化学发光气相色谱仪(GC... 对煤加氢液化过程中含氮化合物的转化行为及在气、液、固三相产物中的赋存形态进行研究,可为低阶煤的高效洁净利用奠定理论基础。在0.01 t/d连续试验装置完成新疆白石湖煤加氢液化连续试验,采用微量硫氮分析仪、氮化学发光气相色谱仪(GC-NCD)、电喷雾电离(ESI)傅里叶变换离子回旋共振质谱(FT-ICR MS)和X射线光电子能谱(XPS)对液化油及残渣中的含氮化合物进行分子识别表征。结果表明,原煤中含量较多的季氮,在液化条件下转化为NH3,迁移到气相产物中,液化残渣中以稠环形态的吡啶氮和吡咯氮为主。氮在气体、低分油、高分油、残渣的比例分别为35.21%、24.41%、19.79%、20.59%。小于170℃液化油馏分含氮化合物含量由高到低排序为:苯胺类>吲哚类>喹啉类>脂肪胺类。大于170℃液化油馏分含氮化合物从N_(1)到N_(X)O_(X)(X=1-2)均存在,主要是苯并咔唑带环烷侧链和苯并咔唑带环烷醚链两类含氮化合物。 展开更多
关键词 低阶煤 加氢液化 含氮化合物 转化行为 赋存形态 液化油馏分 分子识别表征 液化残渣
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Facial Expression Recognition by Split Rectangle Based Adaboost
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作者 Yong-hee HONG Young-joon HAN Hern-soo HAHN 《Journal of Measurement Science and Instrumentation》 CAS 2011年第1期17-20,共4页
The facial expression recognition systn using the Ariaboost based on the Split Rectangle feature is proposed in this paper. This system provides more various featmes in increasing speed and accuracy than the Haarolike... The facial expression recognition systn using the Ariaboost based on the Split Rectangle feature is proposed in this paper. This system provides more various featmes in increasing speed and accuracy than the Haarolike featrue of Viola, which is commonly used for the Adaboost training algorithm. The Split Rectangle feature uses the nmsk-like shape composed with 2 independent rectangles, instead of using mask-like shape of Haar-like feature, which is composed of 2 --4 adhered rectangles of Viola. Split Rectangle feature has less di- verged operation than the Haar-like feaze. It also requires less oper- ation because the stun of pixels requires ordy two rectangles. Split Rectangle feature provides various and fast features to the Adaboost, which produrces the strong classifier with increased accuracy and speed. In the experiment, the system had 5.92 ms performance speed and 84 %--94 % accuracy by leaming 5 facial expressions, neutral, happiness, sadness, anger and surprise with the use of the Adaboost based on the Split Rectangle feature. 展开更多
关键词 split rectangle feature Haar-like discrete adaboost facial expression recognition pattern recognition
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The Politics of Cultural Representation
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作者 Dionisio Nyaga Rose Ann Torres 《Sociology Study》 2015年第9期744-758,共15页
This paper focuses on the representational politics of the Aeta indigenous women healers in Cagayan Valley in the Philippines Indigenous peoples have been represented as backward, irrational, and consequently non-huma... This paper focuses on the representational politics of the Aeta indigenous women healers in Cagayan Valley in the Philippines Indigenous peoples have been represented as backward, irrational, and consequently non-human. For racialized women, it is a double tragedy. They face race and gender misrepresentation. This identification interns them on the margins of society. This colonial representation is being questioned and subverted through the narratives of 12 Aeta women healers in the Philippines. In order to make clarifications as to how they have been represented, the Aeta indigenous women healers discussed and elaborated their indigeneity, language, and spirituality. In turn, they contrast their healing practices with public health. Their hope is to amend the way they have been signified. It is a point where the totalizing narratives meet the subjugated knowledge with a call for fairer representation. This paper confirms that Aeta women healers do not need external representation. They can represent themselves. In fact, they have already been representing themselves. The big question is, are we listening? 展开更多
关键词 REPRESENTATION HEALING cultural representation indigenous Aeta women
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低渗透储层裂缝研究现状及进展 被引量:22
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作者 李理 桑晓彤 陈霞飞 《地球物理学进展》 CSCD 北大核心 2017年第6期2472-2484,共13页
裂缝既是渗流通道,又是储集空间,在低渗透油藏开发中至关重要.国内外学者运用岩石破裂理论、位错理论和分形理论,以及地质、钻井、测井、地震和数值模拟等方法,对裂缝做了大量研究,在形成机理、影响因素、识别及表征和预测等方面取得了... 裂缝既是渗流通道,又是储集空间,在低渗透油藏开发中至关重要.国内外学者运用岩石破裂理论、位错理论和分形理论,以及地质、钻井、测井、地震和数值模拟等方法,对裂缝做了大量研究,在形成机理、影响因素、识别及表征和预测等方面取得了以下诸多进展:(1)从成因上,普遍认为剪裂缝和张裂缝分别遵循Coulomb准则和Griffith准则,裂缝位错模型和各向异性强度准则等考虑了岩石力学性质和岩层的非均质性,更能真实地表达各向异性裂缝的成因;(2)关于影响因素,认为现今裂缝是不同时期区域、局部构造应力场作用下裂缝叠加的结果,主应力的大小、方向控制了裂缝的发育及分布,先期裂缝通过影响局部应力来制约后期裂缝的分布,而储层的非均质性也会主导裂缝的发育和扩展;(3)在裂缝识别方面,岩心观察是基础、测井方法是有效手段,二者能够实现井眼附近10 m内裂缝的定性—定量识别.借助数学及计算机模拟,井震结合识别裂缝是今后发展的趋势;(4)关于裂缝表征,岩心—分形—应力-应变方法实现了点、线—面—体裂缝参数三位一体的定量表征,并逐步由均一化表征到更好地反映低渗储层非均质性及不同时期裂缝参数的表征;(5)在预测方面,曲率法和构造应力场数值模拟能够实现对裂缝局部-整体的预测,分形方法能够更精确、更客观的预测裂缝,裂缝位错预测模型通过岩石-裂缝-应力场的各向异性利用裂缝发育指数来预测、评价裂缝. 展开更多
关键词 低渗透储层 裂缝 成因 识别表征 预测 影响因素
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Frequency-hopping transmitter fingerprint feature recognition with kernel projection and joint representation
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作者 Ping SUI Ying GUO +1 位作者 Kun-feng ZHANG Hong-guang LI 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2019年第8期1133-1147,共15页
Frequency-hopping(FH)is one of the commonly used spread spectrum techniques that finds wide applications in communications and radar systems because of its inherent capability of low interception,good confidentiality,... Frequency-hopping(FH)is one of the commonly used spread spectrum techniques that finds wide applications in communications and radar systems because of its inherent capability of low interception,good confidentiality,and strong antiinterference.However,non-cooperation FH transmitter classification is a significant and challenging issue for FH transmitter fingerprint feature recognition,since it not only is sensitive to noise but also has non-linear,non-Gaussian,and non-stability characteristics,which make it difficult to guarantee the classification in the original signal space.Some existing classifiers,such as the sparse representation classifier(SRC),generally use an individual representation rather than all the samples to classify the test data,which over-emphasizes sparsity but ignores the collaborative relationship among the given set of samples.To address these problems,we propose a novel classifier,called the kernel joint representation classifier(KJRC),for FH transmitter fingerprint feature recognition,by integrating kernel projection,collaborative feature representation,and classifier learning into a joint framework.Extensive experiments on real-world FH signals demonstrate the effectiveness of the proposed method in comparison with several state-of-the-art recognition methods. 展开更多
关键词 Frequency-hopping Fingerprint feature Kernel function Joint representation Transmitter recognition
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