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Layering-based Breakpoint Handling in Contour Line Extraction 被引量:1
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作者 CHENDan LONGYi CAIJinhua 《Geo-Spatial Information Science》 2003年第4期32-38,72,共8页
This paper deals withthe automatic connection of contourlines extracted from a scanned browngeographical map. For the variety oftopographical elements contained on amap, the factors causing the interrup-tion of contou... This paper deals withthe automatic connection of contourlines extracted from a scanned browngeographical map. For the variety oftopographical elements contained on amap, the factors causing the interrup-tion of contour line are also multiform,which make the connection task verydifficult. On the basis of separatingthose elements always making the con-tours break and regarding them as ref-erent layers, a layering-based methodis presented. The purpose is to takeinto account property information (likeinclination and configuration) of con-tour lines when they come across otherdifferent symbols, such as gully, cliff,dry land and elevation annotation etc.In this paper, the authors propose thatit should be far more effective and di-rect to adopt different algorithmic op-erators to different factors than usingsingle one operator to all. 展开更多
关键词 contour line BREAKPOINT extraction CONNECTION
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Processing of Laser Scanner Data and Extraction of Structure Lines Using Methods of the Image Processing 被引量:21
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作者 SUILi-chun 《测绘学报》 EI CSCD 北大核心 2004年第1期63-70,共8页
激光扫描数据提供了一种新的手段用于获取高精度的数字地形表面模型。原始的航空激光扫描数据表达的是一些非规则分布的“点云” ,这些非规则分布的点需要进行有效的事后处理。这种事后处理有 2个目的 :一是将那些分布在地表面上的点 (... 激光扫描数据提供了一种新的手段用于获取高精度的数字地形表面模型。原始的航空激光扫描数据表达的是一些非规则分布的“点云” ,这些非规则分布的点需要进行有效的事后处理。这种事后处理有 2个目的 :一是将那些分布在地表面上的点 (即地面点 )与分布在非地表面上的点 (譬如树木、房屋或汽车上的点 ,即非地面点 )进行有效的分离 ;二是从分离后的地面点中提取结构线 ,用于建立高精度的数字地面模型。作者发展了一系列的基于数字形态学理论和稳健参数估计理论的方法用于分离和探测地面点。这里所介绍和开发的提取结构线的算法建立在数字图像处理和表面曲率理论的基础上。这些算法同样可以扩展地用于其他领域。所介绍的基于数字图像处理理论处理原始的航空激光扫瞄数据和提取结构线的方法取得了很好的结果。 展开更多
关键词 激光扫描 数学形态学 稳健估计 数字图像处理 结构线提取
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Study on Edge Extraction Methods for Image-based Icing On-line Monitoring on Overhead Transmission Lines 被引量:14
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作者 WANG Xiao-peng HU Jian-lin +2 位作者 WU Bin DU Lin SUN Cai-xin 《高电压技术》 EI CAS CSCD 北大核心 2008年第12期2687-2693,共7页
A new method of measuring the icing thickness of transmission lines on-line is proposed in this paper.In this method,the pictures of transmission lines which are photoed by the camera on the iron tower are processed i... A new method of measuring the icing thickness of transmission lines on-line is proposed in this paper.In this method,the pictures of transmission lines which are photoed by the camera on the iron tower are processed immediately to extract the edges of the transmission line conductor and transmission line insulators.The icing thickness can be gained by comparing the edges of the iced transmission line and the uniced one.Two icing image edge extraction methods are described in detail,that is,a method based on the combination of the wavelet transform and the floating threshold method and a method based on the combination of the optimal threshold method and the mathematical morphology transform.The icing images from the artificial climatic chamber and transmission lines are used to test the methods above.The results show that the method based on the wavelet transform and the floating threshold method does well in the extraction of relatively smooth edges,such as glaze icing on conductor and icing on the insulator;meanwhile,the method based on the optimal threshold method and the mathematical morphology transform does well in the edge extraction of icing on the conductor,especially the opaque rime icing on the conductor with complicated edges. 展开更多
关键词 输电线路 覆冰层 边缘提取方法 小波转换 图像
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Determination of inorganic anions in ethyl acetate by in-line hollow fiber membrane extraction with ion chromatography 被引量:1
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作者 Zhen Zhen Hu Ying Ying Zhong Yun Chang Fan Yan Zhu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1498-1501,共4页
In this work, a novel hollow fiber membrane extractor was set up to extract inorganic anions from ethyl acetate using deionized water. Inorganic anions in slightly soluble organic solvents can be determined by the in-... In this work, a novel hollow fiber membrane extractor was set up to extract inorganic anions from ethyl acetate using deionized water. Inorganic anions in slightly soluble organic solvents can be determined by the in-line hollow fiber membrane extractor coupled with ion chromatography at first time. Different aspects of the extraction procedure such as magnetic stirring speed, extraction flow rate and extraction time were optimized to achieve high extraction efficiency and good separation results. Satisfactory linear range, limits of detection and good repeatability were obtained. The procedure was applied to analyze inorganic anions in two commercial ethyl acetate samples. 展开更多
关键词 Inorganic anions Ethyl acetate In-line hollow fiber membrane extraction Ion chromatography
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Extraction of Phenolic Compounds from Olive Leaf Extracts and Their Effect on Proliferation of Human Carcinoma Cell Lines
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作者 Diana Martinho Amin Karmali Eduardo Rosa 《Agricultural Sciences》 2019年第10期1271-1285,共15页
The aim of this work was to evaluate the effect of different olive leaf extracts (OLE) from different leaf growing stages on human carcinoma cell lines. OLE were tested in human carcinoma cell lines in vitro and cells... The aim of this work was to evaluate the effect of different olive leaf extracts (OLE) from different leaf growing stages on human carcinoma cell lines. OLE were tested in human carcinoma cell lines in vitro and cells were plated in 96-microtiter culture plates for each OLE concentration. Fresh (F) and freeze-dried (FD) leaves exhibited phenolic compounds in the range of 2.09 ± 0.10 to 8.44 ± 0.64 and 7.72 ± 0.56 to 24.65 ± 1.9 mg gallic acid equivalents/g leaves, respectively. OLE from several Portuguese olive tree cultivars were found to inhibit the growth of human carcinoma cell lines in a range of 2.09 - 8.44 μg phenolic compound/well (209 - 844 μg/ml) and 0.07 - 2.40 μg phenolic compounds/well (7 - 240 μg/ml) for fresh and freeze-dried leaves, respectively. Young (Y) leaves have revealed the highest cell growth inhibition ranging from about 95% for Cobran?osa, followed by 90% for Cobran?osa, 90% for Arbequina and 75% for Arbequina for cell lines A549, HeLa, A431 and OE21, respectively. The lowest cell growth inhibition (35%) was observed for Galega (Y) leaf extract on cell line A549. However, FD samples exhibited a distinctive pattern since cell growth inhibition was highest at highest extract dilution tested, for A431 (Galega Y) followed by A549 (Cobran?osa Y) with cell inhibition of 75% and 70%, respectively. The data presented in this work strongly suggest that OLEs inhibit the growth of human carcinoma cell lines. 展开更多
关键词 OLIVE Leaf extracts ANTI-PROLIFERATION of HUMAN Carcinoma Cell lines FREEZE-DRIED LEAVES Phenolic Compounds YOUNGER and Older OLIVE LEAVES Portuguese OLIVE Cultivars
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Data Pre-processing and Stroke Segment Extraction for On-line Handwritten Chinese Character Recognition
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作者 唐降龙 舒文豪 +1 位作者 刘家锋 李铁才 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第3期76-81,共6页
The stroke segments:' are proposed to be used as the basic features for handwritten Chinese character recognition. In this way, it is possible to overcome the difFiculties of unstable stroke information caused by ... The stroke segments:' are proposed to be used as the basic features for handwritten Chinese character recognition. In this way, it is possible to overcome the difFiculties of unstable stroke information caused by stroke Joinings. The techniques of data pre-processing and stroke segment extraction have been described. In extracting stroke segment, not only the characteristics of the stroke itself, but also its absolute positions as well as relative positions with other strokes in the character have been taken into account.The primitive features for recognition were extracted under these comprehensive considerations. 展开更多
关键词 ss: ON-line CHINESE CHARACTER RECOGNITION SEGMENT extraction
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A Robust Model Fitting-based Method for Transmission Line Extraction from Airborne LiDAR Point Cloud Data
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作者 Juntao YANG Zhizhong KANG Zhou YANG 《Journal of Geodesy and Geoinformation Science》 2021年第3期60-71,共12页
Airborne Light Detection And Ranging(LiDAR)can provide high-quality three-dimensional information for the safety inspection of electricity corridors.However,the robust extraction of transmission lines from airborne po... Airborne Light Detection And Ranging(LiDAR)can provide high-quality three-dimensional information for the safety inspection of electricity corridors.However,the robust extraction of transmission lines from airborne point cloud data is still greatly challenging.Therefore,this paper proposes a robust transmission line extraction method based on model fitting from airborne point cloud data.First,the candidate power line generation method based on height information is used to reduce the computational complexity at the subsequent steps and the false positives in the extracted results.Then,on the basis of the block-and-slice-constraint Euclidean clustering,a linear structure recognition method based on RANdom SAmple Consensus(RANSAC)is proposed to produce the initial individual transmission line components.Finally,a robust nonlinear least square-based fitting method is developed for the individual transmission line to generate the parameters of its mathematical model for further optimizing the extraction.Experiments were performed on LiDAR point cloud data captured from the helicopter and Unmanned Aerial Vehicle(UAV)platform.Results indicate that the proposed method can efficiently extract the different types of transmission lines along electricity corridors,with the average precision of approximately 98.1%,the average recall of approximately 95.9%,and the average quality of approximately 94.2%,respectively. 展开更多
关键词 airborne LiDAR transmission line extraction unsupervised method random sample consensus
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Online-SPE-UPLC-MS/MS检测生活污水中20种毒品
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作者 裴海燕 鄢茜 +5 位作者 周衍霄 张宏建 朱思琪 杨继伟 俞晓峰 赵鹏 《化学研究与应用》 CAS 北大核心 2024年第2期413-423,共11页
对生活污水的前处理进行优化,建立了一种在线固相萃取-超高效液相色谱-串联质谱法(Online-SPE-UPLC-MS/MS)同时测定污水中20种毒品及人口标记物的方法。用金属螯合剂Na_(2)EDTA·2H_(2)O处理污水后加入同位素内标,接着用滤膜过滤后... 对生活污水的前处理进行优化,建立了一种在线固相萃取-超高效液相色谱-串联质谱法(Online-SPE-UPLC-MS/MS)同时测定污水中20种毒品及人口标记物的方法。用金属螯合剂Na_(2)EDTA·2H_(2)O处理污水后加入同位素内标,接着用滤膜过滤后,以双柱交替模式上样。用Waters Oasis HLB固相萃取柱(2.1 mm×30 mm,20μm)进行富集浓缩后,用流动相将固相萃取柱上吸附的目标物反冲洗到Waters ACQUITY UPLC HSS T3色谱柱(2.1 mm×100 mm,1.8μm)上。柱温40℃,以乙腈-0.1%(体积分数)甲酸水溶液为流动相,采用梯度程序洗脱。采用电喷雾离子源正离子、多反应监测(MRM)模式定量检测。可替宁的线性范围在20~5000 ng·L^(-1),其余20种物质的线性范围在1~250 ng·L^(-1)之间,相关系数R2均大于0.99,检出限在0.01~0.25 ng·L^(-1)之间,加标回收率在91.57%~113.94%,精密度均小于15%。基于Online-SPE-UPLC-MS/MS建立了同时测定污水中20种毒品及人口标记物方法,该方法操作简单、灵敏高,具有良好的准确度和精密度,已成功应用于城市污水中的毒品检测,用于监测毒品滥用情况。 展开更多
关键词 在线固相萃取 双柱交替 超高液相色谱串联质谱 污水 毒品
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Sub-pixel extraction of laser stripeand itsapplication in laser plane calibration 被引量:2
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作者 陈平 张志胜 +1 位作者 戴敏 陈恺 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期107-112,共6页
For calibrating the laser plane to implement 3D shape measurement, an algorithm for extracting the laser stripe with sub-pixel accuracy is proposed. The proposed algorithm mainly consists of two stages: two-side edge... For calibrating the laser plane to implement 3D shape measurement, an algorithm for extracting the laser stripe with sub-pixel accuracy is proposed. The proposed algorithm mainly consists of two stages: two-side edge detection and center line extraction. First, the two-side edge of laser stripe is detected using the principal component angle-based progressive probabilistic Hough transform and its width is calculated through the distance between these two edges. Secondly, the center line of laser strip is extracted with 2D Taylor expansion at a sub-pixel level and the laser plane is calibrated with the 3D reconstructed coordinates from the extracted 2D sub-pixel ones. Experimental results demonstrate that the proposed method can not only extract the laser stripe at a high speed, nearly average 78 ms/frame, but also calibrate the coplanar laser stripes at a low error, limited to 0.3 mm. The proposed algorithm can satisfy the system requirement of two-side edge detection and center line extraction, and rapid speed, high precision, as well as strong anti-jamming. 展开更多
关键词 sub-pixel extraction center line extraction laser plane calibration progressive probabilistic Hough transform (PPHT) principal component (PC) angle 2D Taylor expan- sion
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Apoptosis of neoplasm cell lines induced byhepatic peptides extracted from sucking porcine hepatocytes 被引量:11
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作者 Kong XP Zou QY +3 位作者 Li RB Zheng PL Yang LP Jin SW 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第5期435-439,共5页
关键词 NEOPLASM cell lines APOPTOSIS HEPATIC PEPTIDES HEPATIC extracts liver neoplasms HEPATOCYTES
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In vitro antiproliferative and apoptosis inducing effect of a methanolic extract of Azadirachta indica oil on selected cancerous and noncancerous cell lines
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作者 Muhammad Kashif Dongwook Kim Gonhyung Kim 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2018年第10期555-561,共7页
Objective: To find the cytotoxic and apoptotic effects of neem oil extract on the selected cancerous(A-549, PC-3 and DU-145) and noncancerous(NIH3T3 and CCD-18Co) cell lines.Methods: Viability and cytotoxic effect ind... Objective: To find the cytotoxic and apoptotic effects of neem oil extract on the selected cancerous(A-549, PC-3 and DU-145) and noncancerous(NIH3T3 and CCD-18Co) cell lines.Methods: Viability and cytotoxic effect induced by the extract was measured by using MTT assay and apoptotic effect of the extract was evaluated by using Hoechst 33342 and propidium iodide dual staining through a fluorescent microscope and activity of caspases 3, 8 and 9 through colorimetric assay kits. Results: The results showed that neem oil extract significantly reduced the viability in all selected cancer cells treated with varying concentrations of extract as compared with untreated cells and had less effect on noncancerous cell lines. It significantly increased the percentage of necrotic and apoptotic cells, and caspases 3, 8 and 9 activities in all cancer cells treated with extract as compared with untreated cells whereas no effect on noncancerous cell lines. It suggested that neem oil extract exerted a higher cytotoxic effect on cancer cells than normal cells and lower concentration induced apoptosis only in cancer cells.One of the apoptosis-inducing mechanism was through the activation of caspases signaling pathways. Conclusion: Conclusively, it implies that neem oil extract may contain one or more potential agents that can be used as a safe and effective anticancer therapy. 展开更多
关键词 NEEM OIL extract Cell lines Cytotoxicity APOPTOSIS Caspase activity
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Enhanced cytotoxic effect on human lung carcinoma cell line(A549) by gold nanoparticles synthesized from Justicia adhatoda leaf extract
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作者 D.Latha P.Prabu +3 位作者 C.Arulvasu R.ManikANDan S.Sampurnam V.Narayanan 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2018年第11期540-547,共8页
Objective: To synthesize bio-inspired gold nanoparticles(AuNPs) using the leaf extract of Justicia adhatoda and evaluate the anti-cancer activity on human lung cancer cell line(A549).Methods: Synthesis of AuNPs was do... Objective: To synthesize bio-inspired gold nanoparticles(AuNPs) using the leaf extract of Justicia adhatoda and evaluate the anti-cancer activity on human lung cancer cell line(A549).Methods: Synthesis of AuNPs was done using an aqueous leaf extract of Justicia adhatoda as a green route. The bio-synthesized AuNPs were confirmed and characterized by using various spectral studies such as UV-Vis spectrum, Scanning Electron Microscope with EDAX, Transmission Electron Microscope, Fourier Transmission Infrared Spectroscope analysis and Surface Enhanced Raman Spectroscopy. The cell viability was determined by MTT reduction assay. In addition, cytomorphology and the nuclear morphological study of A549 cell line was observed under fluorescence microscope. Results: UV-Vis spectrum showed surface plasmon resonance peak at 547 nm, scanning electron microscope and transmission electron microscope studies showed the monodispersed spherical shape and its average size in the range of 40.1 nm was noticed. Fourier Transmission Infrared Spectroscope analysis confirmed that the C=O group of amino acids of proteins had strong ability to bind with the surface of nanoparticle. Interestingly, our results also demonstrated inhibited proliferation of A549 cell line by MTT(IC50 value: 80 μg/mL). Cell morphology was observed and cell death was caused by apoptosis as revealed by propidium iodide staining. Conclusions: The current study proves the anticancer potential of bio-synthesized AuNPs. Thus, synthesized AuNPs can be used for the treatment of human lung cancer cell(A549) and it can be exploited for drug delivery in future. 展开更多
关键词 Justicia adhatoda Leaf extract AuNPs CYTOTOXICITY A549 cell line
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THE EXTRACTION EQUILIBRIUM MODEL AND SIMULATION OF COUNTERCURRENT SOLVENT EXTRACTION OF Gd-Tb-Dy-HCl-HEH(EHP)-KEROSENE SYSTEM
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作者 黄文梅 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第4期252-255,共4页
The extraction equilibrium mathematic models for gadolinium,terbium and dysprosium in HCl-1.5 mol/L HEH(EHP)system covering a relatively wide range of lanthanide concentration and acidity,have been developed.There are... The extraction equilibrium mathematic models for gadolinium,terbium and dysprosium in HCl-1.5 mol/L HEH(EHP)system covering a relatively wide range of lanthanide concentration and acidity,have been developed.There are four independent variables and nine parameters.The average relative error is 4.56%.A computer program for the simulation of the counter current solvent extraetion process has also been written.Thus,the Gd,Tb and Dy concentrations in both aqueous and organic phase in eaeh stage as well as the aqueous acidity may be calculated.Product purities,distribution ratio and extraction factors may also be obtained thereby.The simulation results so obtained may serve as the referenee data for designing solvent ex- traction processes including those processes providing apart from the conventional outgoing organic stream, outgoing raffinate and an extra outgoing third exit stream either organic or aqueous. 展开更多
关键词 line RE Gd DY EHP THE extraction EQUILIBRIUM MODEL AND SIMULATION OF COUNTERCURRENT SOLVENT extraction OF Gd-Tb-Dy-HCl-HEH KEROSENE SYSTEM
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Plane extraction for navigation of humanoid robot
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作者 张彤 肖南峰 《Journal of Central South University》 SCIE EI CAS 2011年第3期627-632,共6页
In order to make the humanoid robot walk freely in complicated circumstance, the reliable capabilities for obtaining plane information from its surroundings are demanded. A system for extracting planes from data taken... In order to make the humanoid robot walk freely in complicated circumstance, the reliable capabilities for obtaining plane information from its surroundings are demanded. A system for extracting planes from data taken by stereo vision was presented, After the depth image was obtained, the pixels of each line were scanned and split into straight line segments. The neighbouring relation of line segments was kept in link structure. The groups of three line segments were selected as seed regions. A queue was maintained for storing seed regions, and then the plane region was expanded around the seed region. The process of region growing continued until the queue of seed regions was empty. After trimming, the edges of the planes became smooth. In the end, extracted planes were obtained. In the experiment, two models were used: pipe and stairs. Two planes in pipe mode/and six planes in stairs model were extracted exactly. The speed and precision of algorithm can satisfy the demands of humanoid robot's navigation. 展开更多
关键词 humanoid robot NAVIGATION line segments splitting region growing plane extraction depth image
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Situation and Developing Trend of Rare-Earth Countercurrent Extraction Processes Control 被引量:1
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作者 柴天佑 杨辉 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第5期604-610,共7页
On the basis of the description of the rare-earth countercurrent extraction process, the on-line detecting method and equipments of rare-earth elements and the application in the process of the rare-earth countercurre... On the basis of the description of the rare-earth countercurrent extraction process, the on-line detecting method and equipments of rare-earth elements and the application in the process of the rare-earth countercurrent extraction are summarized. The procedure simulation of the computer, the automation control method and its current application are also mentioned in the process of rare-earth countercurrent extraction. The method of soft sensor is proposed. Optimal control method based on object-oriented rare-earth countercurrent extraction process and integrated automation system composed of process management system and process control system are presented, which are the developing direction of the automation of rare-earth countercurrent extraction process. 展开更多
关键词 countercurrent extraction on-line analysis soft-sensor process control integrated automation system rare earths
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Breakthrough in the China's Separation Technology for Extraction of Rare Earth Elements
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作者 HAO Ziguo FEI Hongcai +1 位作者 LIU Lian Susan TURNER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第6期1743-1744,共2页
Separation technology of rare earth elements (REEs), as the critical step in the separation process, had long been fraught with technical difficulty. A research project conducted by Baotou Shibo Rare Earth Extracti... Separation technology of rare earth elements (REEs), as the critical step in the separation process, had long been fraught with technical difficulty. A research project conducted by Baotou Shibo Rare Earth Extraction & Equipment Co. Ltd., Baotou REE Research Institute, and Baotou Steel & REE Group Hi-Tech Co. Ltd (Inner Mongolia), has successfully solved the problem using a centrifugal extractor and advanced techniques to achieve a key breakthrough. 展开更多
关键词 line Breakthrough in the China’s Separation Technology for extraction of Rare Earth Elements REE
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Analytical and Numerical Model Confrontation for Transfer Impedance Extraction in Three-Dimensional Radio Frequency Circuits
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作者 Olivier Valorge Fengyuan Sun +3 位作者 Jean-Etienne Lorival Mohamed Abouelatta-Ebrahim Francis Calmon Christian Gontrand 《Circuits and Systems》 2012年第2期126-135,共10页
3D chip stacking is considered known to overcome conventional 2D-IC issues, using through silicon vias to ensure vertical signal transmission. From any point source, embedded or not, we calculate the impedance spread ... 3D chip stacking is considered known to overcome conventional 2D-IC issues, using through silicon vias to ensure vertical signal transmission. From any point source, embedded or not, we calculate the impedance spread out;our ultimate goal will to study substrate noise via impedance field method. For this, our approach is twofold: a compact Green function or a Transmission Line Model over a multi-layered substrate is derived by solving Poisson’s equation analytically. The Discrete Cosine Transform (DCT) and its variations are used for rapid evaluation. Using this technique, the substrate coupling and loss in IC’s can be analyzed. We implement our algorithm in MATLAB;it permits to extract impedances between any pair of embedded contacts. Comparisons are performed using finite element methods. 展开更多
关键词 Through Silicon Via (TSV) Green’s Function Transmission line Model Radio Frequency (RF) Transfer IMPEDANCE extraction
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五台山壁画人物线描图生成算法
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作者 焦莉娟 王文剑 李朝霞 《计算机应用与软件》 北大核心 2024年第10期242-246,共5页
五台山壁画图像因褪化而导致颜色不均匀、部分边缘轮廓像素灰度缺失,用传统的梯度法生成的线描图存在噪点多且线条不连续的问题。提出一种基于色调补偿及双卷积技术的壁画人物线描图生成算法。在计算梯度幅值时引入色调梯度进行有效的... 五台山壁画图像因褪化而导致颜色不均匀、部分边缘轮廓像素灰度缺失,用传统的梯度法生成的线描图存在噪点多且线条不连续的问题。提出一种基于色调补偿及双卷积技术的壁画人物线描图生成算法。在计算梯度幅值时引入色调梯度进行有效的色调补偿,同时通过两种针对离散噪点的卷积模板实现去麻点功能。对五台山壁画人物图像的线描图生成实验的结果表明,该方法在去噪的基础上有效改善了轮廓线不连续的问题。 展开更多
关键词 五台山壁画 壁画线描图 轮廓提取 微分算子
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基于改进Grabcut分割与多特征决策融合的电力线放电痕迹识别
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作者 邹国锋 邵楠 +2 位作者 王连辉 梁栋 徐丙垠 《科学技术与工程》 北大核心 2024年第28期12239-12250,共12页
电力线触树故障中,导线表面的遗留痕迹是事故防治和责任认定的重要依据,但目前中外针对触树后电力线放电痕迹特征规律和辨识方法的研究极其匮乏。为此,搭建10 kV中压线路触树放电实验平台,采集放电后的导线表面痕迹图像,并对导线表面痕... 电力线触树故障中,导线表面的遗留痕迹是事故防治和责任认定的重要依据,但目前中外针对触树后电力线放电痕迹特征规律和辨识方法的研究极其匮乏。为此,搭建10 kV中压线路触树放电实验平台,采集放电后的导线表面痕迹图像,并对导线表面痕迹特征进行系统分析,为人工巡检和智能化痕迹识别提供基础依据。然后,提出改进型Grabcut前景提取方法,综合利用U^(2)Net的自动分割特点和Grabcut的高精度优势,解决Grabcut算法中初始框无法自动确定的问题,实现复杂背景下导线痕迹区域自动精准分割。最后,提出基于低层纹理、颜色特征和高层深度特征的导线表面痕迹全面表征,并采用多数投票规则实现低层和高层特征识别结果决策融合,获得导线痕迹辨识结果,测试实验中平均识别准确率达到91.68%,证明了方法的有效性。 展开更多
关键词 树线放电 前景提取 低层特征 深度特征 决策融合 痕迹识别
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基于离散数据流分割算法的预测方法
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作者 孙丽君 李方方 胡祥培 《管理科学学报》 CSSCI CSCD 北大核心 2024年第9期48-61,共14页
离散数据流具有不确定性高、演变趋势多变以及多极值性等特征.针对这些特征带来的预测难以兼顾准确性和实时性的问题,提出了基于离散数据流分割算法的预测方法.该方法融合了短期趋势提取与分割点在线自适应检测:预测前基于非参数回归短... 离散数据流具有不确定性高、演变趋势多变以及多极值性等特征.针对这些特征带来的预测难以兼顾准确性和实时性的问题,提出了基于离散数据流分割算法的预测方法.该方法融合了短期趋势提取与分割点在线自适应检测:预测前基于非参数回归短期预测模型和改进的趋势提取算法获取短期(预测日)趋势,提前挖掘、分析预测日的短期趋势规律,以用于在线预测;预测时主要针对在线的数据流,基于假设检验自适应地检测分割点,以解决分割点难以确定的问题,并基于短期趋势修正分割点处的预测模型,减少了预测模型对缓冲数据的依赖.数值实验结果验证了本研究所提预测方法的有效性和可行性. 展开更多
关键词 离散数据流预测 在线数据流分割 非参数回归 趋势提取
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