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A modified method of discontinuity trace mapping using three-dimensional point clouds of rock mass surfaces 被引量:14
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作者 Keshen Zhang Wei Wu +3 位作者 Hehua Zhu Lianyang Zhang Xiaojun Li Hong Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2020年第3期571-586,共16页
This paper presents an automated method for discontinuity trace mapping using three-dimensional point clouds of rock mass surfaces.Specifically,the method consists of five steps:(1)detection of trace feature points by... This paper presents an automated method for discontinuity trace mapping using three-dimensional point clouds of rock mass surfaces.Specifically,the method consists of five steps:(1)detection of trace feature points by normal tensor voting theory,(2)co ntraction of trace feature points,(3)connection of trace feature points,(4)linearization of trace segments,and(5)connection of trace segments.A sensitivity analysis was then conducted to identify the optimal parameters of the proposed method.Three field cases,a natural rock mass outcrop and two excavated rock tunnel surfaces,were analyzed using the proposed method to evaluate its validity and efficiency.The results show that the proposed method is more efficient and accurate than the traditional trace mapping method,and the efficiency enhancement is more robust as the number of feature points increases. 展开更多
关键词 Rock mass DISCONTINUITY Three-dimensional point clouds Trace mapping
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Customer Requirements Mapping Method Based on Association Rule Mining for Mass Customization 被引量:2
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作者 夏世升 王丽亚 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第3期291-296,共6页
Customer requirements analysis is the key step for product variety design of mass customiza-tion(MC). Quality function deployment (QFD) is a widely used management technique for understanding the voice of the customer... Customer requirements analysis is the key step for product variety design of mass customiza-tion(MC). Quality function deployment (QFD) is a widely used management technique for understanding the voice of the customer (VOC), however, QFD depends heavily on human subject judgment during extracting customer requirements and determination of the importance weights of customer requirements. QFD pro-cess and related problems are so complicated that it is not easily used. In this paper, based on a general data structure of product family, generic bill of material (GBOM), association rules analysis was introduced to construct the classification mechanism between customer requirements and product architecture. The new method can map customer requirements to the items of product family architecture respectively, accomplish the mapping process from customer domain to physical domain directly, and decrease mutual process between customer and designer, improve the product design quality, and thus furthest satisfy customer needs. Finally, an example of customer requirements mapping of the elevator cabin was used to illustrate the proposed method. 展开更多
关键词 association rules analysis requirements mapping classification mechanism generic bills of material (GBOM) mass customization
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DWI联合T_(2) mapping技术在预测乳腺良恶性病变中的价值 被引量:3
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作者 程雪 陈春妙 +1 位作者 杨伟斌 纪建松 《中国中西医结合影像学杂志》 2023年第4期420-423,共4页
目的:探讨DWI联合T_(2) mapping技术对乳腺良恶性病变的鉴别诊断价值。方法:回顾性分析经手术病理证实的乳腺肿块患者82例,其中良性病变32例(良性组),恶性病变50例(恶性组);术前均行乳腺MRI检查,比较2组的ADC值及T_(2)值,分析其对良恶... 目的:探讨DWI联合T_(2) mapping技术对乳腺良恶性病变的鉴别诊断价值。方法:回顾性分析经手术病理证实的乳腺肿块患者82例,其中良性病变32例(良性组),恶性病变50例(恶性组);术前均行乳腺MRI检查,比较2组的ADC值及T_(2)值,分析其对良恶性鉴别的诊断效能。结果:2组病灶形态、ADC值及T_(2)值差异均有统计学意义(均P<0.05)。ADC值、T_(2)值及两者联合诊断乳腺良恶性病变ROC曲线的AUC分别为0.793(95%CI 0.689~0.875)、0.749(95%CI 0.641~0.838)、0.854(95%CI 0.759~0.923)。结论:DWI联合T_(2) mapping技术可提高对乳腺病变良恶性鉴别诊断的准确率,为临床诊疗提供帮助。 展开更多
关键词 弥散加权成像 T_(2)mapping 乳腺肿块 诊断 鉴别
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Identification of proteins of human colorectal carcinoma cell line SW480 by two-dimensional electrophoresis and MALDI-TOF mass spectrometry 被引量:1
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作者 Ying-Tao Zhang Yi-Ping Geng +3 位作者 Le Zhou Bao-Chang Lai Lv-Sheng Si Yi-Li Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第30期4679-4684,共6页
AIM: To conduct bhe proteomic analysis of human colorectal carcinoma cell line, SW480 by using two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption /ionization-time of flight mass spectromet... AIM: To conduct bhe proteomic analysis of human colorectal carcinoma cell line, SW480 by using two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption /ionization-time of flight mass spectrometry (MALDITOFMS). METHODS: The total proteins of human colorectal carcinoma cell line, SW480 were separated with 2-DE by using immobilized pH gradient strips and visualized by staining with silver nitrate. The gel images were acquired by scanner and 2-DE analysis software, Image Master 2D Elite. Nineteen distinct protein spots were excised from gel randomly and digested in gel by TPCK-trypsin. Mass analysis of the byptic digest peptides mixture was performed by using MALDI-TOF MS. Peptide mass fingerprints (PMFs) obtained by the MALDI-TOF analysis were used to search NCBI, SWISS-PROT and MSDB databases by using Mascot software. RESULTS: PMF maps of all spots were obtained by MALDI-TOF MS and thirteen proteins were preliminarily identified. CONCLUSION: The methods of analysis and identification of protein spots of tumor cells in 2-DE gel with silver staining by MALDI-TOF MS derived PMF have been established. Protein expression profile of SW480 has been obtained. It is demonstrated that a combination of proteomics and cell culture is a useful approach to comprehend the process of colon carcinogenesis. 展开更多
关键词 Colorectal carcinoma SW480 cell line Twodimensional electrophoresis maldi-tof MS Peptide mass fingerprinting
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Multimodal element(including lithium)mapping in a Mg-9Li-4Al-1Zn alloy
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作者 Yu Zhang Yang Liu +3 位作者 Zhuoran Zeng Nick Birbilis Philip N.H.Nakashima Laure Bourgeois 《Journal of Magnesium and Alloys》 CSCD 2024年第11期4468-4480,共13页
Determining the distribution of alloying elements,particularly lithium,is crucial for a holistic understanding of magnesium-lithium-based alloys.In this work,a bespoke ratio spectrum-imaging method based on electron e... Determining the distribution of alloying elements,particularly lithium,is crucial for a holistic understanding of magnesium-lithium-based alloys.In this work,a bespoke ratio spectrum-imaging method based on electron energy-loss spectroscopy,in combination with time-of-flight secondary ion mass spectrometry,energy-dispersive X-ray spectroscopy and Z-contrast imaging,was applied to an as-rolled LAZ941 alloy(Mg-9Li-4Al-1Zn in wt.%).This was done to characterize the distribution of alloying elements,including the distribution of solute in the magnesium matrix.The applications of different mapping techniques revealed that precipitates with two different morphologies are rich in Li,Al and Zn,compared to their surrounding matrix.Additionally,it was confirmed that theβ-phase of the alloy contains higher Li and lower Mg concentrations when compared to theα-phase.This study demonstrated the effectiveness and accuracy of the ratio spectrum-imaging method for mapping the elemental distribution(including lithium)in a range of Li-containing materials. 展开更多
关键词 Magnesium alloys Lithium distribution mapping Solute content mapping Phase determination Electron energy-loss spectroscopy(EELS) Time-of-flight secondary ion mass spectrometry(ToF-SIMS) Scanning transmission electron microscopy(STEM)
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MALDI-TOF-MS用于组合化学肽库的鉴定 被引量:1
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作者 赵睿 罗佳 +2 位作者 熊少祥 辛斌 刘国诠 《分析测试学报》 CAS CSCD 北大核心 2004年第z1期78-79,共2页
  组合化学是一种快速制备大量相关化合物,并可快速对其进行生物活性筛选的革新性的技术和方法.组合化学法自问世以来在生命科学和医药科学技术等领域获得了飞速发展.组合化学肽库已成为同时制备大量不同序列多肽的方法,并已广泛用于...   组合化学是一种快速制备大量相关化合物,并可快速对其进行生物活性筛选的革新性的技术和方法.组合化学法自问世以来在生命科学和医药科学技术等领域获得了飞速发展.组合化学肽库已成为同时制备大量不同序列多肽的方法,并已广泛用于抗原决定簇、生物分子相互作用、亲和抑制剂、新药筛选等研究.在亲和筛选研究中,合成组合肽库的评价以及结构鉴定是研究成败的关键步骤之一.…… 展开更多
关键词 Peptide library maldi-tof HPLC mass spectrometry
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肝癌细胞线粒体蛋白的MALDI-TOF质谱鉴定方法研究 被引量:1
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作者 蒋代凤 邱宗荫 +3 位作者 李兴 黄开顺 滕永真 张晓萍 《重庆医科大学学报》 CAS CSCD 2005年第4期485-488,共4页
目的:探索胶上蛋白原位酶切、肽质量指纹图(PMF)分析以及数据库检索方法的优化条件,建立适合于亚细胞比较蛋白质组学研究的质谱鉴定策略。方法:从考马斯亮蓝染色的2-DE胶上取下牛血清白蛋白(BSA)标准蛋白进行胶内原位酶切,与基质(CHCA)... 目的:探索胶上蛋白原位酶切、肽质量指纹图(PMF)分析以及数据库检索方法的优化条件,建立适合于亚细胞比较蛋白质组学研究的质谱鉴定策略。方法:从考马斯亮蓝染色的2-DE胶上取下牛血清白蛋白(BSA)标准蛋白进行胶内原位酶切,与基质(CHCA)混匀后进行MALDI-TOF MS分析;对来源于人肝细胞癌细胞株QGY-7703线粒体的差异表达的候选蛋白点L9,按照通过BSA标准蛋白优化的条件进行MALDI-TOF质谱鉴定;其肽质量指纹图(PMF)经MS-Fit检索。结果:经数据库检索,BSA的肽质量指纹图(PMF)匹配肽质量数为10/11,序列覆盖率为19%,说明实验条件完全可信。候选蛋白点L9的PMF数据经数据库检索后,排名前两位的蛋白均为OXCT(3-oxoacid CoA transferase 1 precursor),其匹配肽段为9/13,序列覆盖率为24%;且OXCT的理论分子量(56kda),理论等电点(7.1),与胶上L9蛋白的位置相符。故候选蛋白点L9确认为OXCT(3-oxoacid CoA transferase 1 precursor)。结论:本文所确定的鉴定策略适用于线粒体比较蛋白质组学的研究。 展开更多
关键词 线粒体 蛋白质组学 肽质量指纹图(PMF) 基质辅助激光解吸离子化-飞行时间质谱(maldi-tof mass) 二维电泳(2-DE)
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基于Map/Reduce的朴素贝叶斯数据分类算法研究 被引量:12
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作者 崔良中 郭福亮 宋建新 《海军工程大学学报》 CAS 北大核心 2019年第4期7-10,共4页
针对目前机器学习研究领域中的数据分类问题,选择朴素贝叶斯算法作为研究对象。首先,通过对样本数据特征属性的权重进行加权调整,提高算法处理的准确率;然后,改进朴素贝叶斯算法分类器模型,使其能够利用Map/Reduce并行编程模型,采用多... 针对目前机器学习研究领域中的数据分类问题,选择朴素贝叶斯算法作为研究对象。首先,通过对样本数据特征属性的权重进行加权调整,提高算法处理的准确率;然后,改进朴素贝叶斯算法分类器模型,使其能够利用Map/Reduce并行编程模型,采用多计算资源节点并行处理,进一步提高处理速度。最后,对UCI dataset数据库进行实验验证,结果表明:改进后的算法在海量数据分类处理中具有更好的性能表现。 展开更多
关键词 map/Reduce并行编程模型 数据分类算法 贝叶斯算法 海量数据处理
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一种基于MapReduce的电子地图数字水印处理方法 被引量:1
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作者 方晓乐 王倩雪 +1 位作者 陈鑫祥 吴永静 《计算机应用与软件》 CSCD 2016年第10期211-214,共4页
电子地图在互联网上发布后,可以通过数字水印技术来保护其所有者的版权。为了提高数字水印算法嵌入的执行效率,提出一种并行的电子地图数字水印嵌入法。该方法基于并优化了MapReduce编程模型,再结合一种具有高鲁棒性、基于离散余弦变换(... 电子地图在互联网上发布后,可以通过数字水印技术来保护其所有者的版权。为了提高数字水印算法嵌入的执行效率,提出一种并行的电子地图数字水印嵌入法。该方法基于并优化了MapReduce编程模型,再结合一种具有高鲁棒性、基于离散余弦变换(DCT)的数字水印法,对海量的电子地图瓦片进行并行的水印加载。最后在测试实验中表明,该方法较传统模式,提升了工作效率。 展开更多
关键词 电子地图 mapREDUCE DCT 数字水印 并行处理 云计算 海量
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Highly sensitive detection of phosphopeptides with superparamagnetic Fe_(3)O_(4)@mZrO_(2) core-shell microspheres-assisted mass spectrometry 被引量:2
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作者 Ruifang Gao Jin Li +6 位作者 Rui Shi Yang Zhang Fuzhou Ouyang Ting Zhang Lihua Hu Guoqiang Xu Jian Liu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第24期234-242,共9页
Protein phosphorylation is one of the most important post-translational modifications.It is an active research area to study phosphoproteomics for discovery of disease biomarkers and druggable targets.Here we report t... Protein phosphorylation is one of the most important post-translational modifications.It is an active research area to study phosphoproteomics for discovery of disease biomarkers and druggable targets.Here we report the development of superparamagnetic Fe_(3)O_(4)@mZrO_(2) core-shell microspheres with mesoporous structures for highly efficient enrichment of phosphopeptides.We have demonstrated that the mesoporous ZrO_(2) layer dramatically improves the selective enrichment of phosphopeptides.Our approach allows for in-situ elution and sensitive identification of both mono-phosphorylated and multiphosphorylated peptides in MALDI-TOF mass spectrometry,with the detection limit of down to the femtomole range.The target phosphopeptides can reliably be enriched for MS analysis from various complex samples including the spiked protein digests and tumor cell lysates.The Fe_(3)O_(4)@mZrO_(2) coreshell microspheres promise a useful tool for phosphoproteomics by allowing for highly efficient and selective enrichment of the crucial signaling regulators in a low abundance. 展开更多
关键词 Core-shell microspheres Mesoporous structure Protein phosphorylation maldi-tof mass spectrometry Enrichment technologies
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Combination of MALDI-TOF mass spectrometry with immobilized enzyme microreactor for peptide mapping 被引量:1
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作者 姜泓海 邹汉法 +5 位作者 汪海林 张强 倪坚毅 张清春 郭忠 陈小明 《Science China Chemistry》 SCIE EI CAS 2000年第6期625-633,共9页
Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been combined with immobilized enzyme microreactor for the rapid, sensitive, and accurate tryptic mapping of protein and polypeptides. The t... Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been combined with immobilized enzyme microreactor for the rapid, sensitive, and accurate tryptic mapping of protein and polypeptides. The technique utilizes the trypsin microreactor by immobilized enzyme on the glycidyl methacrylate (GMA)-modified cellulose membrane. The membrane micro-reactor was used for the tryptic mapping of cytochrome C and the results were compared with those obtained by using free trypsin. A significant increase in the overall sensitivity of the process was observed using the membrane microreactor, as well as the elimination of background signals due to the autolysis of the trypsin. Further, membrane microreactor digestions were found to be rapid and convenient. 展开更多
关键词 IMMOBILIZED ENZYME MICROREACTOR glycidyl METHACRYLATE (GMA)-modified CELLULOSE membrane maldi-tof MS peptide mapping.
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Mass Valuation and the Implementation Necessity of GIS (Geographic Information System) in Albania 被引量:1
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作者 Elfrida Shehu Elda Maci Vorpsi Alma Afezolli 《Journal of Civil Engineering and Architecture》 2015年第12期1506-1512,共7页
In the last decade, mass valuation system is applied in Albania in addition to individual valuation system for real estate valuation. This system is used for compiling the land value map and apartments value map. Due ... In the last decade, mass valuation system is applied in Albania in addition to individual valuation system for real estate valuation. This system is used for compiling the land value map and apartments value map. Due to the lack of experience in the compilation of these maps, the methodology of valuation is based on the experiences of other countries with similar development of real estate market. The mass assessment, which is applied in determining the values for specific purposes, such as expropriation, compensation and taxes for property transfer through the methodology adopted for this aim, is analyzed in the light of the finding of issues that accompany this application. The aim of this research is to highlight the problems to provide the ways of overcoming them in order to approximate the values of map values with market values. The mass appraisal process requires effective valuation models and proper management of resources. Its accuracy depends upon the extent and quality of property data available. Because of this reason, it is recommended the usage of the GIS (geographic information system), an automated system for collection and processing of the data necessary for valuation, as the first point of integration between two process of valuation, individual and mass valuation. 展开更多
关键词 Real estate mass valuation GIS map value.
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MAP洗涤红细胞和生理盐水洗涤红细胞临床效果的对比 被引量:5
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作者 徐敏 《中外医疗》 2019年第20期175-177,共3页
目的比较MAP保存与生理盐水混悬的洗涤红细胞输血治疗的临床效果。方法方便选取2015年1月-2017年12月该院84例输注洗涤红细胞的患者为研究对象,依据细胞保存方法不同分为实验组(MAP保存,42例)和对照组(NS混悬,42例),对比观察两组输血前... 目的比较MAP保存与生理盐水混悬的洗涤红细胞输血治疗的临床效果。方法方便选取2015年1月-2017年12月该院84例输注洗涤红细胞的患者为研究对象,依据细胞保存方法不同分为实验组(MAP保存,42例)和对照组(NS混悬,42例),对比观察两组输血前后血红蛋白水平变化,统计不良反应。结果实验组洗涤红细胞输注后血红蛋白(63.7±8.5)g/L高于输注前(52.7±9.1)g/L,差异有统计学意义(t=4.630,P<0.05),与对照组输注后(64.2±8.0)g/L差异无统计学意义(t=4.727,P>0.05),不良反应4.76%,与对照组差异无统计学意义(χ^2=2.093,P>0.05)。结论洗涤红细胞以MAP保存或生理盐水混悬进行输血治疗均可提高血红蛋白水平,临床效果确切。不过前者不良反应率偏高,对于输血不良反应高危患者,建议以生理盐水洗涤红细胞为优选,以保证输血安全。 展开更多
关键词 洗涤红细胞 map 生理盐水 细胞质量 血红蛋白
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Detection of Sialylated N-Linked Glycans by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry
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作者 PENG Yanfei XU Xiaojuan 《Wuhan University Journal of Natural Sciences》 CAS 2014年第3期245-252,共8页
Native and methyl-esterified sialylated glycans were analyzed with 2,4,6-trihydroxyacetophenone(THAP)and 2,5-dihydroxybenzoic acid(DHB)as matrix by a matrix-assisted laser desorption/ionization time-of-flight mass... Native and methyl-esterified sialylated glycans were analyzed with 2,4,6-trihydroxyacetophenone(THAP)and 2,5-dihydroxybenzoic acid(DHB)as matrix by a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer(MALDI-TOF MS).High quality negative-ion spectra of commercial sialylated glycan were obtained with THAP as matrix.Detection limit of the glycan was less than 0.1 pmol.After methyl esterification of sialic acid(SA)residue,sialylated glycans were detected sensitively in the positive-ion mode using DHB as matrix.Neutral and sialylated glycans from the mixture of asialofetuin and fetuin were methylesterified and simultaneously recognized in one manipulation.Methyl esterification of SA residue offers a convenient and sensitive way to identify the structure of N-linked glycans for glycan profiling. 展开更多
关键词 sialic acid glycans methyl esterification matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(maldi-tof MS)
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Mass Spectrometric Identification of Propionibacterium Isolates Requires Database Enrichment
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作者 Sophie Edouard Carine Couderc +1 位作者 Didier Raoult Pierre-Edouard Fournier 《Advances in Microbiology》 2012年第4期497-504,共8页
Propionibacterium species are mostly environmental bacteria, some being commensal of mammals including humans, and sometimes pathogenic. These bacteria are poorly identified using routine laboratory methods. Recently,... Propionibacterium species are mostly environmental bacteria, some being commensal of mammals including humans, and sometimes pathogenic. These bacteria are poorly identified using routine laboratory methods. Recently, Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS) has emerged as a rapid and efficient method to identify bacterial species. We evaluated the use of MALDI-TOF-MS for identification of all validated Propionibacterium species. Only four of the 15 tested reference strains (26.7%) were correctly identified at the species level, and P. acnes, the most common human pathogenic species was not identified. When applying MALDI-TOF-MS to 48 P. acnes strains, only 18.7% were correctly identified, suggesting an intraspecific variability of proteic profiles among Propionibacterium strains. However, by enriching the Bruker database with spectra from five of these strains and re-testing the other 43 strains against this new database, 93.0% were correctly identified. Our study demonstrates that MALDI-TOF-MS may be used for the identification of Propionibacterium isolates but requires a database enrichment in spectra from additional isolates. 展开更多
关键词 PROPIONIBACTERIUM Propionibacterium acnes maldi-tof mass Spectrometry
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基于SuperMap GIS的网络发布基础地形图数据库更新实践
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作者 高红心 李楠 《城市勘测》 2011年第6期68-70,共3页
以西安市基础地形图数据局域网络发布项目为基础,简述了基于SuperMap GIS和Oracle的基础地形图发布数据库更新的方法和实现过程,对超图SDX+For Oracle空间数据库和本项目更新过程中出现的问题进行了详细的分析,并得出了高效可行的处理... 以西安市基础地形图数据局域网络发布项目为基础,简述了基于SuperMap GIS和Oracle的基础地形图发布数据库更新的方法和实现过程,对超图SDX+For Oracle空间数据库和本项目更新过程中出现的问题进行了详细的分析,并得出了高效可行的处理方法。 展开更多
关键词 SUPERmap GIS SDX+ For ORACLE 空间数据库 海量基础地形图 数据更新 局域网络发布
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山西省早白垩世下地壳地质图:基于镜质组反射率证据的修正
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作者 焦守涛 刘东娜 +14 位作者 张旗 靳职斌 张玉生 原杰 周李岗 刘铁翊 解团结 范宗胜 闫彤彤 周新鹏 张双奎 卫倩倩 闫涛 张坤 尹碧菡 《地学前缘》 北大核心 2025年第1期418-431,共14页
我们已经根据花岗岩的资料编制了一份山西省早白垩世下地壳地质图,本文增加了镜质组反射率资料,重新编制了一份山西省早白垩世下地壳地质图。经过对比,得出了许多新认识。对比说明,在下地壳填图中,镜质组反射率是一个非常有用的资料。... 我们已经根据花岗岩的资料编制了一份山西省早白垩世下地壳地质图,本文增加了镜质组反射率资料,重新编制了一份山西省早白垩世下地壳地质图。经过对比,得出了许多新认识。对比说明,在下地壳填图中,镜质组反射率是一个非常有用的资料。镜质组反射率可以记录它形成以后所能够达到的最高温度,是煤田和石油地质部门成熟度测量中广泛应用且可靠的方法之一。镜质组反射率方法对岩石学和矿床学也非常有用,因此可以根据镜质组反射率资料推测深部是否有隐伏岩体以及隐伏岩体的分布和规模,推测下地壳底部是否有地幔上涌以及地幔上涌的分布。利用镜质组反射率分布寻找隐伏岩体,再根据隐伏岩体找矿,是一个找矿的新方法。文中根据山西省镜质组反射率的分布,推测在若干R_(o)>3.0%的地区的深部有可能发现隐伏岩体,其中,祁县隐伏岩体已经被钻探验证所证实。山西省煤矿很多,凡是无烟煤分布区均是寻找隐伏岩体的有利地区。文中还根据镜质组反射率资料对山西省早白垩世下地壳地质图进行了修改,指出山西省中部和南部的深部为大片中生代(主要是早白垩世)花岗岩分布区,也是早白垩世时地幔上涌的区域。根据地层资料和花岗岩资料推测山西省北部(大同以北)为地壳厚度正常区,南部为地壳加厚区(为中国东部高原的一部分)。南部为地幔上涌区,北部无地幔上涌迹象;故南部下地壳为高温榴辉岩相区,北部下地壳为低温榴辉岩相区。地表有矿产分布的区域,下地壳为含流体榴辉岩相区。山西省中部和西部的下地壳可能为榴辉岩相-麻粒岩相过渡区,暗示中国东部高原在山西省可能呈现为向西缓慢下降的趋势。 展开更多
关键词 山西省 镜质组反射率 无烟煤 下地壳地质图 隐伏岩体 高原 早白垩世
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使用卷积神经网络分辨核子有效质量劈裂
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作者 李理 张英逊 +4 位作者 杨钧评 崔莹 陈响 王馨钰 赵凯 《核动力工程》 北大核心 2025年第2期68-75,共8页
为精确分辨核物质中质子与中子有效质量劈裂,本研究提出一种使用双通道输入的卷积神经网络(CNN)确定核子有效质量劈裂的新方法。该方法的主要思想是利用CNN学习理论模型计算质子、中子产额的纵、横动量分布。研究采用的理论模型为改进... 为精确分辨核物质中质子与中子有效质量劈裂,本研究提出一种使用双通道输入的卷积神经网络(CNN)确定核子有效质量劈裂的新方法。该方法的主要思想是利用CNN学习理论模型计算质子、中子产额的纵、横动量分布。研究采用的理论模型为改进的量子分子动力学模型(ImQMD),有效相互作用参数为SkM^(*)与SLy4两套参数,分别对应于中子有效质量大于质子有效质量和中子有效质量小于质子有效质量。通过对大量模型数据的学习,建立了利用CNN分辨核子有效质量劈裂的方法。对3套丰中子弹靶系统^(48)Ca+^(208)Pb、^(48)Ca+^(124)Sn和^(124)Sn+^(124)Sn的分析表明,3套系统均在束流能量为50 MeV/u时分辨精度最高,均超过99.5%。在束流能量为270 MeV/u时,3套系统的分辨精度仍均高于93%。通过遮挡法对质子、中子产额的纵、横动量分布图像重要性区域进行了考查,给出了3套系统在50 MeV/u时的重要性图分析,指出二维动量图像中,低横动量区域对于有效质量劈裂的分辨有更大的重要性。 展开更多
关键词 核子有效质量劈裂 卷积神经网络(CNN) 丰中子系统 机器学习 重要性图
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液质联用法测定重组人脑利钠肽的质量肽图
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作者 张竞 安进城 +3 位作者 李丹丹 周志艳 任新桐 邹卫 《中国医药科学》 2025年第5期17-20,66,共5页
目的建立重组人脑利钠肽(rhBNP)的肽图分析方法,同时绘制其质量肽图并鉴定二硫键位点。方法摸索合适的酶切条件,用液质联用的方法绘制质量肽图和定位二硫键,并进行重复性、精密度和耐用性相关验证。结果rhBNP经还原及烷基化后进行酶切,... 目的建立重组人脑利钠肽(rhBNP)的肽图分析方法,同时绘制其质量肽图并鉴定二硫键位点。方法摸索合适的酶切条件,用液质联用的方法绘制质量肽图和定位二硫键,并进行重复性、精密度和耐用性相关验证。结果rhBNP经还原及烷基化后进行酶切,胰蛋白酶与蛋白质量比为1∶100时,可以得到稳定的肽图谱。通过分析理论结果,确认二硫键位置。方法学验证结果表明,该方法重复性、精密度及耐用性良好。对连续3批生产的中试产品进行肽图分析,供试品与对照品的肽图谱完全一致。结论本研究建立的肽图分析方法可应用于rhBNP的鉴别和质量控制。 展开更多
关键词 液质联用 肽图 重组人脑利钠肽 心力衰竭
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基于正态张量投票的岩体点云轨迹线识别
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作者 杨义 万旸璐 +1 位作者 安庆 班亚 《武汉理工大学学报(信息与管理工程版)》 2025年第5期677-682,共6页
为自动准确地从岩体三维点云数据中提取岩体结构面轨迹线,并计算出平均迹线的大小,从特征点提取、分组、轨迹生长、连接和轨迹长度5个角度,提出了一种基于岩体表面三维点云的不连续面轨迹映射的迹线测绘方法。利用正态张量投票理论检测... 为自动准确地从岩体三维点云数据中提取岩体结构面轨迹线,并计算出平均迹线的大小,从特征点提取、分组、轨迹生长、连接和轨迹长度5个角度,提出了一种基于岩体表面三维点云的不连续面轨迹映射的迹线测绘方法。利用正态张量投票理论检测和提取轨迹特征点;利用最小生成树法在迹段生长阶段进行轨迹生长,减少冗余连线;利用改进的采样方法计算平均迹长。分析各个阶段的参数指标的敏感性,基于敏感性分析结果建立具有适用性的指标范围并分析影响因素,通过对比分析和抗噪性分析验证了方法稳定性。所提取到的岩体轨迹线准确有效,验证了新识别方法的有效性。 展开更多
关键词 岩体 三维点云 轨迹映射 正态张量投票 最小生成树
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