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磁性液体Rosensweig单峰传感应用研究进展
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作者 崔海蓉 《机械工程师》 2024年第5期9-12,共4页
介绍了一种磁性液体传感应用的新方法。它以磁性液体单个Rosensweig尖峰作为感测元件,检测外部激励信号,输出电信号。可以用于惯性传感、流量传感、微阻尼器等领域。综述了Rosensweig单峰形成的条件和特性,以及其传感应用的机理和进展。
关键词 磁性液体 Rosensweig尖峰 传感应用 检测机理
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Application of Remote Sensing and GIS in Mineral Alteration Mapping and Lineament Extraction Case of Oudiane Elkharoub (Requibat Shield, Northern of Mauritania)
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作者 Ould Mahmoud Hdeid Yousra Morsli +6 位作者 Mohamed Raji Zouhir Baroudi Malika Adjour Khaled Cheikh Nebagha Zein El Arby Vetah Mohamed El Moktar Isselmou Brahim Vall 《Open Journal of Geology》 CAS 2024年第9期823-854,共32页
The integration of remotely sensed data allowed the successful characterization of the mineral alteration zones of the Oudiane Elkharoub area in the Northeastern part of Reguibat Shield using image transformation tech... The integration of remotely sensed data allowed the successful characterization of the mineral alteration zones of the Oudiane Elkharoub area in the Northeastern part of Reguibat Shield using image transformation techniques. As both chemical and geochemical analyses showed significant Au, Ag, Cu, Pb, Mn, Cr, Ni, Th and Y anomalies, it’s very interesting to apply the remote sensing and GIS in mineral resources mapping. The remote sensing is a direct adjunct to the field, lithologic and structural mapping, and more recently, GIS has played an important role in the study of mineralization areas. The integration of several evidential maps highlighted the plausible areas with high concentrations of chlorite, epidote, kaolinite, calcite, alunite, hematite, illite and sulfur among other key mineral alterations that reflect the intensity of hydrothermal effects and the probable sites of ore bodies. The methodological approach integrates geological information acquired from Aster and Landsat 8 OLI/TIRS (Operational Land Imager/Thermal InfraRed Sensor) images and a multi-criteria GIS analysis. The superimposition of various lineament and hydrothermal alteration maps and the consideration of precious and base metal indicators allowed the zoning of sites likely to contain mineral concentrations. Remote sensing becomes an important tool for locating mineral deposits in its own right, when the primary and secondary processes of mineralization result in the formation of spectral anomalies. Reconnaissance lithological mapping is usually the first step of mineral resource mapping. This is complimented with structural mapping, as mineral deposits usually occur along or adjacent to geologic structures, and alteration mapping, as mineral deposits are commonly associated with hydrothermal alteration of the surrounding rocks. Ground truthing and laboratory studies including XRD analysis were utilized to verify the results. 展开更多
关键词 Remote sensing GIS ASTER Landsat 8 (OLI/TIRS) Structure Mineralization ALTERATION MINERAL LINEAMENT Reguibat Shield Oudiane Elkharoub
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Land Use Land Cover Analysis for Godavari Basin in Maharashtra Using Geographical Information System and Remote Sensing
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作者 Pallavi Saraf Dattatray G. Regulwar 《Journal of Geographic Information System》 2024年第1期21-31,共11页
The dynamic transformation of land use and land cover has emerged as a crucial aspect in the effective management of natural resources and the continual monitoring of environmental shifts. This study focused on the la... The dynamic transformation of land use and land cover has emerged as a crucial aspect in the effective management of natural resources and the continual monitoring of environmental shifts. This study focused on the land use and land cover (LULC) changes within the catchment area of the Godavari River, assessing the repercussions of land and water resource exploitation. Utilizing LANDSAT satellite images from 2009, 2014, and 2019, this research employed supervised classification through the Quantum Geographic Information System (QGIS) software’s SCP plugin. Maximum likelihood classification algorithm was used for the assessment of supervised land use classification. Seven distinct LULC classes—forest, irrigated cropland, agricultural land (fallow), barren land, shrub land, water, and urban land—are delineated for classification purposes. The study revealed substantial changes in the Godavari basin’s land use patterns over the ten-year period from 2009 to 2019. Spatial and temporal dynamics of land use/cover changes (2009-2019) were quantified using three Satellite/Landsat images, a supervised classification algorithm and the post classification change detection technique in GIS. The total study area of the Godavari basin in Maharashtra encompasses 5138175.48 hectares. Notably, the built-up area increased from 0.14% in 2009 to 1.94% in 2019. The proportion of irrigated cropland, which was 62.32% in 2009, declined to 41.52% in 2019. Shrub land witnessed a noteworthy increase from 0.05% to 2.05% over the last decade. The key findings underscored significant declines in barren land, agricultural land, and irrigated cropland, juxtaposed with an expansion in forest land, shrub land, and urban land. The classification methodology achieved an overall accuracy of 80%, with a Kappa Statistic of 71.9% for the satellite images. The overall classification accuracy along with the Kappa value for 2009, 2014 and 2019 supervised land use land cover classification was good enough to detect the changing scenarios of Godavari River basin under study. These findings provide valuable insights for discerning land utilization across various categories, facilitating the adoption of appropriate strategies for sustainable land use in the region. 展开更多
关键词 GIS Remote sensing Land Use Land Cover Change Change Detection Supervised Classification
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Quantifying River Bank Erosion and Accretion Patterns along the Gorai River in Kushtia, Bangladesh: A Geospatial Analysis Utilizing GIS and Remote Sensing Techniques
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作者 Chisti Muzahid Samsunnahar Popy +6 位作者 Rifat Islam Md. Shafiqul Ahsan Emon Md. Selim Reja Md. Mustafizur Rahman Jubayer Hoque Md. Golam Rabbani Saim Raiyan 《Journal of Geographic Information System》 2024年第1期70-88,共19页
River bank erosion is a natural process that occurs when the water flow of a river exceeds the bank’s ability to withstand it. It is a common phenomenon that causes extensive land damage, displacement of people, loss... River bank erosion is a natural process that occurs when the water flow of a river exceeds the bank’s ability to withstand it. It is a common phenomenon that causes extensive land damage, displacement of people, loss of crops, and infrastructure damage. The Gorai River, situated on the right bank of the Ganges, is a significant branch of the river that flows into the Bay of Bengal via the Mathumati and Baleswar rivers. The erosion of the banks of the Gorai River in Kushtia district is not a recent occurrence. Local residents have been dealing with this issue for the past hundred years, and according to the elderly members of the community, the erosion has become more severe activities. Therefore, the main objective of this research is to quantify river bank erosion and accretion and bankline shifting from 2003 to 2022 using multi-temporal Landsat images data with GIS and remote sensing technique. Bank-line migration occurs as a result of the interplay and interconnectedness of various factors such as the degree of river-related processes such as erosion, transportation, and deposition, the amount of water in the river during the high season, the geological and soil makeup, and human intervention in the river. The results show that the highest eroded area was 4.6 square kilometers during the period of 2016 to 2019, while the highest accreted area was 7.12 square kilometers during the period of 2013 to 2016. However, the erosion and accretion values fluctuated from year to year. 展开更多
关键词 Erosion and Accretion Geographic Information System (GIS) Remote sensing Satellite Image Bankline Shifting
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摄影测量与遥感领域主题演化研究——以《ISPRS Journal of Photogrammetry and Remote Sensing》期刊为例
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作者 杨珂 李青山 金心怡 《测绘技术装备》 2024年第3期1-8,共8页
为了便于相关领域的研究人员了解遥感学领域的整体发展状态并进行量化分析,本文以国际摄影测量与遥感学会(ISPRS)官方刊物作为研究数据,从主题挖掘和主题关联的角度出发,在计量分析的基础上,基于隐含狄利克雷分布(LDA)和word2vec的主题... 为了便于相关领域的研究人员了解遥感学领域的整体发展状态并进行量化分析,本文以国际摄影测量与遥感学会(ISPRS)官方刊物作为研究数据,从主题挖掘和主题关联的角度出发,在计量分析的基础上,基于隐含狄利克雷分布(LDA)和word2vec的主题演化模型进行分析与研究,重点解决了摄影测量与遥感学领域主题挖掘、学科领域主题关联、学科主题演化建模和主题演化知识图谱等问题,展示了遥感学领域的主题动态演化过程。主题演化研究结果表明:1)主题强度总排名前三的主题分别是激光扫描技术、摄影测量、遥感信息提取与分类;2)随着深度学习的深入发展,遥感学领域的深度学习相关应用研究热度逐渐攀升;3)环境遥感相关方向的研究热度相对稳定,演化关系多局限于相关研究内部。 展开更多
关键词 主题演化 摄影测量与遥感 科学计量学 隐含狄利克雷分布 word2vec
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Mapping Energy Expansion: Remote Sensing Insights into Oil and Gas Infrastructure and Land Use Changes in Midland, TX
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作者 Nastaran Abdoli Mahdi Alipour Mehrnaz Pasokhi 《Journal of Geoscience and Environment Protection》 2024年第7期89-108,共20页
Rapid expansion in global energy demand driven primarily by oil and gas consumption has spurred significant environmental concerns. This study delves into the intricate relationship between energy development and envi... Rapid expansion in global energy demand driven primarily by oil and gas consumption has spurred significant environmental concerns. This study delves into the intricate relationship between energy development and environmental impacts focusing on Midland County, Texas, a pivotal region within the Permian Basin. Leveraging satellite imagery and Geographic Information Systems (GIS) techniques, the research meticulously examines land use dynamics from 2001 to 2019. The findings illuminate a marked decline in vegetation health and density attributable to the burgeoning oil and gas infrastructure in the area. Moreover, the analysis underscores the emergence of barren lands and the displacement of agricultural areas, indicative of the profound alterations in land cover patterns over the study period. These insights underscore the urgent need for concerted efforts to mitigate the adverse environmental effects of energy expansion, emphasizing the importance of collaborative approaches to foster sustainable land use practices. Additionally, the study explores the socio-economic implications of land use changes, addressing how energy expansion affects local communities and economies. Previous studies have emphasized the need for comprehensive assessments of cumulative environmental impacts, advocating for the implementation of effective mitigation strategies. 展开更多
关键词 Remote sensing Land Cover Change Energy Infrastructure Energy Sprawl Texas
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Study on Ecological Change Remote Sensing Monitoring Method Based on Elman Dynamic Recurrent Neural Network
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作者 Zhen Chen Yiyang Zheng 《Journal of Geoscience and Environment Protection》 2024年第4期31-44,共14页
In this paper, Hailin City of Heilongjiang Province, China is taken as the research area. As an important city in Heilongjiang Province, China, the sustainable development of its ecological environment is related to t... In this paper, Hailin City of Heilongjiang Province, China is taken as the research area. As an important city in Heilongjiang Province, China, the sustainable development of its ecological environment is related to the opening up, economic prosperity and social stability of Northeast China. In this paper, the remote sensing ecological index (RSEI) of Hailin City in recent 20 years was calculated by using Landsat 5/8/9 series satellite images, and the temporal and spatial changes of the ecological environment in Hailin City were further analyzed and the influencing factors were discussed. From 2003 to 2023, the mean value of RSEI in Hailin City decreased and increased, and the ecological environment decreased slightly as a whole. RSEI declined most significantly from 2003 to 2008, and it increased from 2008 to 2013, decreased from 2013 to 2018, and increased from 2018 to 2023 again, with higher RSEI value in the south and lower RSEI value in the northwest. It is suggested to appropriately increase vegetation coverage in the northwest to improve ecological quality. As a result, the predicted value of Elman dynamic recurrent neural network model is consistent with the change trend of the mean value, and the prediction error converges quickly, which can accurately predict the ecological environment quality in the future study area. 展开更多
关键词 Remote sensing Ecological Index Long Time Series Space-Time Change Elman Dynamic Recurrent Neural Network
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基于Compressed Sensing框架的图像多描述编码方法 被引量:21
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作者 刘丹华 石光明 +2 位作者 周佳社 高大化 吴家骥 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2009年第4期298-302,共5页
基于新兴的压缩感知(Compressed Sensing,CS)理论,提出了一种抗丢包能力强且结构简单易实现的多描述编码方法.首先对变换后的图像进行交织抽取分块,再对各子块进行随机观测、量化、打包形成多个描述子码流.解码端根据接收码流情况通过... 基于新兴的压缩感知(Compressed Sensing,CS)理论,提出了一种抗丢包能力强且结构简单易实现的多描述编码方法.首先对变换后的图像进行交织抽取分块,再对各子块进行随机观测、量化、打包形成多个描述子码流.解码端根据接收码流情况通过求解优化问题重建原图像.由于随机观测过程简单易实现,故该方法可以以较低的计算复杂度构造出较多的描述子.实验结果表明,在同样的丢包率下,本文方法的重构质量(PSNR)明显优于SPIHT多描述编码方法,且计算复杂度较低. 展开更多
关键词 多描述编码 压缩感知 随机观测 优化问题
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结合非线性GRAPPA与SENSE的并行磁共振成像 被引量:2
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作者 蒋明峰 朱礼涛 +2 位作者 汪亚明 夏灵 龚莹岚 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2014年第10期1865-1870,共6页
针对SENSE并行磁共振成像中采用补零缺失数据方法估计敏感度分布不准确性的问题,提出采用非线性GRAPPA方法估算缺失的K空间欠采样数据.计算并行线圈的敏感度分布,将这些敏感度分布应用于SENSE并行磁共振成像.采用不同加速因子的脑磁共振... 针对SENSE并行磁共振成像中采用补零缺失数据方法估计敏感度分布不准确性的问题,提出采用非线性GRAPPA方法估算缺失的K空间欠采样数据.计算并行线圈的敏感度分布,将这些敏感度分布应用于SENSE并行磁共振成像.采用不同加速因子的脑磁共振K空间欠采样数据以验证提出算法的重建性能.实验结果表明,与单一的非线性GRAPPA和SENSE重建算法相比,该混合NLGRAPPA-SENSE算法在加速因子较大时可以重建出更加准确的磁共振图像,具有更低的噪声功率(AP)和更高的信噪比(SNR)性能. 展开更多
关键词 并行磁共振成像(pMRI) 非线性GRAPPA 敏感度编码(sensE) NLGRAPPA-sensE
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SENSE心脏阵列线圈在前列腺MRI检查中的初步应用研究 被引量:5
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作者 刘金来 沈钧康 +6 位作者 王灌忠 杨晓春 张彩元 周丽娟 徐孝秋 王水珍 钱铭辉 《临床放射学杂志》 CSCD 北大核心 2008年第9期1234-1238,共5页
目的对灵敏度编码(SENSE)心脏阵列线圈和直肠腔内线圈在前列腺MRI检查中的图像质量进行对比研究,初步评价SENSE心脏阵列线圈在前列腺MRI检查中的价值。资料与方法选取前列腺病变患者50例。在相同扫描参数下,均使用SENSE心脏阵列线圈和... 目的对灵敏度编码(SENSE)心脏阵列线圈和直肠腔内线圈在前列腺MRI检查中的图像质量进行对比研究,初步评价SENSE心脏阵列线圈在前列腺MRI检查中的价值。资料与方法选取前列腺病变患者50例。在相同扫描参数下,均使用SENSE心脏阵列线圈和直肠腔内线圈进行前列腺MRI常规检查,对使用两种线圈所分别获得的前列腺轴位(TRA)小视野、薄层T2WI图像的均匀度、对比信噪比(CNR)进行对比分析。结果采用SENSE心脏阵列线圈所获得的图像均匀度优于采用直肠腔内线圈者(配对t检验,P<0.05);采用SENSE心脏阵列线圈所获得的图像CNR亦优于采用直肠腔内线圈者(配对t检验,P<0.05)。结论SENSE心脏阵列线圈在图像均匀度和CNR这两个图像评价指标方面都取得了较好的成像效果,在一定程度上可以替代直肠腔内线圈进行前列腺小视野、薄层、高分辨率T2W成像。 展开更多
关键词 sensE心脏阵列线圈 前列腺 磁共振成像
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Extracting Impervious Surface and Its Change Information Using Satellite Remote Sensing Data 被引量:3
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作者 马雪梅 李希峰 《Agricultural Science & Technology》 CAS 2008年第6期113-117,共5页
Impervious surface is one of the important parameters of valley water circular simulation,scientific estimation for which has significant and practical value for the urban water quantity and process simulation,diffuse... Impervious surface is one of the important parameters of valley water circular simulation,scientific estimation for which has significant and practical value for the urban water quantity and process simulation,diffuse pollution estimating and the forecast of climate changes.The objective of this research is to get the information of impervious surface and its dynamic change.Through the computer-assisted field method,the technologies of decision tree and data mining were applied to withdraw the impervious surface information in research region by the Landsat TM data in 1988,1994 and 2002.The results suggested that the accuracy of impervious surface information extraction in the study area arrived above 94.4% in 2002 image.On this basis,the mixed method was used to extract the location and the types of the impervious surface change.The overall accuracy of monitoring reached 89%,which meets the demand of the hydrological models. 展开更多
关键词 Impervious surface MONITORING REMOTE sensING DECISION TREE classification
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细菌感染性疾病中的对立统一规律与Quorum Sensing系统 被引量:4
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作者 李洪涛 宋建新 《医学与哲学(B)》 2007年第3期45-48,共4页
引起人类细菌性感染的病原菌可以分为条件致病菌和非条件致病菌,不同性质的细菌引起的感染决定了感染矛盾的特殊性,对于不同质的矛盾,只有用不同质的方法才能解决。抗生素的发明和使用为人类控制感染性疾病的同时,这种单纯的“对抗”的... 引起人类细菌性感染的病原菌可以分为条件致病菌和非条件致病菌,不同性质的细菌引起的感染决定了感染矛盾的特殊性,对于不同质的矛盾,只有用不同质的方法才能解决。抗生素的发明和使用为人类控制感染性疾病的同时,这种单纯的“对抗”的解决方法也引出了一些新的矛盾。因此,细菌感染矛盾的特殊性决定我们不能采用千篇一律的“对抗斗争”形式,而必须寻求一种特殊的解决方式。对QS系统的研究发现在细菌表现致病性过程中发挥重要作用,通过QS系统减弱细菌的致病性而不杀死细菌的“抗致病性药物”来治疗感染成为一种新的抗感染思路,这种“抗致病性”概念使我们抗感染的态度从与细菌“对抗”转变为“共生”,因而QS系统可以为这种特殊矛盾提供一个合理的解决方式。 展开更多
关键词 矛盾 对立统一规律 细菌感染 QUORUM sensING
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固醇敏感多肽区(Sterol-sensing dom ain)的分子进化 被引量:6
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作者 胡广安 《河南师范大学学报(自然科学版)》 CAS CSCD 2003年第1期88-92,109,共6页
固醇敏感多肽区 (SSD)在胆固醇自我平衡调节、物质运输以及细胞信号转导中发挥重要的作用 .通过对三界系统中 ,不同门纲代表种 (2 2个种 )的 SSD序列分析发现 ,SSD在组成上有很大的偏向性 ,在三级结构上高度保守 .分子系统树的结果表明 ... 固醇敏感多肽区 (SSD)在胆固醇自我平衡调节、物质运输以及细胞信号转导中发挥重要的作用 .通过对三界系统中 ,不同门纲代表种 (2 2个种 )的 SSD序列分析发现 ,SSD在组成上有很大的偏向性 ,在三级结构上高度保守 .分子系统树的结果表明 SSD明显分为 PTC、NPC1、Ptr、SCAP、Disp、HMGCR和原核生物类 7大分枝 ,功能相关基因的 SSD并不聚集在一起 ,说明 SSD在进化中受到的选择压力是不同的 .推测是一种原始的拥有编码 SSD跨膜结构域序列通过交换转移和其他的编码序列组成新的基因 ,再逐步进化形成固定的功能 ,而 SSD保持了与运输有关的功能 .进一步证实了 Ref[13]提出的 Hh- PTC- Sm o信号系统作用模型 . 展开更多
关键词 固醇敏感多肽区 Sterol-sensing Domain 结构功能 分子进化 序旬分析 分子遗传学
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假单胞菌Quorum sensing调控体系 被引量:1
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作者 张玲华 冯莉 田兴山 《生物技术》 CAS CSCD 2006年第6期86-89,共4页
群体感应(Quorum sensing,QS)是近来受到广泛关注的一种细菌群体行为调控机制,通过感应一些信号分子如酰基高丝氨酸环内酯(acyl-homoserine lactone,AHL)来判断菌群密度和周围环境变化,假单胞菌中同样也有AHL信号分子,当信号达到一定的... 群体感应(Quorum sensing,QS)是近来受到广泛关注的一种细菌群体行为调控机制,通过感应一些信号分子如酰基高丝氨酸环内酯(acyl-homoserine lactone,AHL)来判断菌群密度和周围环境变化,假单胞菌中同样也有AHL信号分子,当信号达到一定的浓度阈值时,能启动菌体中相关基因的表达来适应环境中的变化,从而调节菌体的群体行为(如致病性及群体生长调节)。众多报道说明了假单胞菌的群体感应调节系统是由一些全面的调节子所调控的。本文系统介绍了假单胞菌群体感应调控系统,并分析假单胞菌在该系统中复杂的应答反应。 展开更多
关键词 群体感应 酰基高丝氨酸环内酯 调控 假单胞菌
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PF-FICOTA-SENSE:一种MRI快速重构方法 被引量:2
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作者 李建武 康杨 周金鹏 《自动化学报》 EI CSCD 北大核心 2020年第5期897-908,共12页
如何实现快速磁共振成像(Magnetic resonance imaging,MRI)是MRI医学图像技术发展和应用的关键,现有的快速MRI成像技术在成像速度及成像质量方面仍存在很大的提升空间.本文基于Contourlet变换,对磁共振图像进行稀疏表示,并结合传统PF-CS... 如何实现快速磁共振成像(Magnetic resonance imaging,MRI)是MRI医学图像技术发展和应用的关键,现有的快速MRI成像技术在成像速度及成像质量方面仍存在很大的提升空间.本文基于Contourlet变换,对磁共振图像进行稀疏表示,并结合传统PF-CS-SENSE框架,提出一种基于Contourlet变换的组合MRI重构方法,即PF-FICOTA-SENSE.考虑到组合MRI采样模式、低频数据的对称性以及Contourlet能更好地拟合曲线轮廓等因素,进一步提出一种快速组合MRI方法,该方法通过将低频部分重建由FICOTA重建替换为直接填零的傅里叶重建,来实现快速重建.对比实验表明,无论在MRI重构速度还是重构质量方面,本文算法均能取得更好的性能. 展开更多
关键词 压缩感知 半傅里叶成像 并行成像 PF-FICOTA-sensE
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伽达默尔的“sensus communis”刍论 被引量:3
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作者 何卫平 《广西师范大学学报(哲学社会科学版)》 北大核心 2015年第1期29-34,共6页
"sensus communis"是伽达默尔所看重的西方人文主义的四个基本概念之一,它包含"共通感"和"常识"两个方面的含义,这个概念和另外三个概念"教化"、"判断力"和"趣味"关系密切... "sensus communis"是伽达默尔所看重的西方人文主义的四个基本概念之一,它包含"共通感"和"常识"两个方面的含义,这个概念和另外三个概念"教化"、"判断力"和"趣味"关系密切,是其中的中介和桥梁,它们一起构成了精神科学的真理及其解释学的基础。伽达默尔对这个词的理解既吸收了前人的成果,又纳入一种新的眼光,使之具有了更加深刻的人文主义内涵和解释学的意义。 展开更多
关键词 伽达默尔 共通感 常识 判断力 趣味 解释学
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基于快速分裂Bregman迭代的全变差正则化SENSE磁共振图像重建 被引量:1
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作者 吴春俐 朱学欢 +1 位作者 翟江南 丁山 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2014年第1期24-28,共5页
在并行磁共振成像中,由于敏感度编码(SENSE)重建过程的病态性,当加速因子增大时,其重建图像的信噪比将会明显降低.通过深入分析全变差(TV)正则化的SENSE重建模型,引入一种高效快速的分裂Bregman迭代算法来得到优化解,进而有效改善图像... 在并行磁共振成像中,由于敏感度编码(SENSE)重建过程的病态性,当加速因子增大时,其重建图像的信噪比将会明显降低.通过深入分析全变差(TV)正则化的SENSE重建模型,引入一种高效快速的分裂Bregman迭代算法来得到优化解,进而有效改善图像重建效果.分别对磁共振的体模数据和大脑数据进行仿真实验研究.结果表明,与传统TV正则化SENSE重建相比,此算法不但迭代次数少、收敛速度快,而且能够有效消除混叠伪影,提高图像信噪比并减小归一化均方误差. 展开更多
关键词 敏感度编码(sensE) 磁共振图像重建 全变差正则化 人工时间演化法 分裂Bregman迭代
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灵敏度编码磁共振谱成像(SENSESI)技术及图像重建方法 被引量:1
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作者 黄敏 卢松涛 林家瑞 《北京生物医学工程》 2004年第3期171-174,共4页
传统的相位编码磁共振谱成像 (MRSI)采集数据需要很长的时间 ,使得MRSI在临床上的应用受阻。灵敏度编码磁共振谱成像 (SENSE SI)采用线圈矩阵来并行采集MRSI数据 ,是一种不仅可以大大减少数据采集时间 ,而且不影响空间和谱的分辨率的全... 传统的相位编码磁共振谱成像 (MRSI)采集数据需要很长的时间 ,使得MRSI在临床上的应用受阻。灵敏度编码磁共振谱成像 (SENSE SI)采用线圈矩阵来并行采集MRSI数据 ,是一种不仅可以大大减少数据采集时间 ,而且不影响空间和谱的分辨率的全新方法。在图像重建时利用各个线圈的空间灵敏度来对丢失的编码信息进行恢复 ,将像素折叠的图像进行展开 ,可以得到完全没有重叠伪影的代谢物图像。SENSE SI采集数据的快速性和图像重建的高分辨性为MRSI真正应用于临床打下了坚实的基础。 展开更多
关键词 灵敏度编码 磁共振谱成像 sensE-SI 图像重建 磁共振谱成像
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Application of Remote Sensing Technology in Monitoring Forest Diseases and Pests
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作者 张田 张晓丽 +1 位作者 刘红伟 裴小节 《Plant Diseases and Pests》 CAS 2010年第3期57-62,共6页
Forest diseases and pests affect the forest health and forestry production, the monitoring of forest diseases and pests by remote sensing has great advantages and potential. The principles, the technical methods and t... Forest diseases and pests affect the forest health and forestry production, the monitoring of forest diseases and pests by remote sensing has great advantages and potential. The principles, the technical methods and the main aspects of monitoring forest diseases and pests by remote sensing are described, and the application prospect of this technology is forecasted. 展开更多
关键词 Forest diseases and pests Remote sensing MONITORING
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SENSE B-FFE技术对肝脏占位病变的诊断价值评估 被引量:1
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作者 祝新 《实用医技杂志》 2008年第7期817-819,共3页
目的:探讨敏感性编码(Sensitivity encoding,SENSE)基础上的平衡驱动快速梯度回波(Balance FastF ield echo,B-FFE)序列在肝占位性病变中的应用价值。方法:对161例共有224个肝占位病灶患者应用SENSE B-FFE序列进行检查。224个肝占位病... 目的:探讨敏感性编码(Sensitivity encoding,SENSE)基础上的平衡驱动快速梯度回波(Balance FastF ield echo,B-FFE)序列在肝占位性病变中的应用价值。方法:对161例共有224个肝占位病灶患者应用SENSE B-FFE序列进行检查。224个肝占位病灶中肝脏恶性实质肿块(包括原发性肝癌和实性转移瘤)130个,肝血管瘤45个,肝囊肿49个。结果:肝脏恶性实质肿块、肝血管瘤、肝囊肿平均信号强度(signal intensity SI)及病灶/肝脏信号强度比(le-sion/liver signal intensity ratio SIR)分别为:527.25±31.40、1235.91±32.86和2817.01±28.37及1.55±0.24、3.36±0.11和8.31±0.65,三者差异有统计学意义(P<0.01)。结论:SENSE B-FFE成像技术对肝脏恶性实质肿块、肝血管瘤和肝囊肿的鉴别诊断具有较高的价值。 展开更多
关键词 肝肿瘤 磁共振成像 敏感性编码 平衡 快速梯度回波
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