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Left Bundle Branch Ablation Guided by a Three-Dimensional Mapping System: A Novel Method for Establishing a Heart Failure Animal Model
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作者 Pengkang He Han Jin +3 位作者 Yiran Hu Sixian Weng Sijing Cheng Hao Huang 《Cardiovascular Innovations and Applications》 2023年第1期574-580,共7页
Objective:Few studies have been conducted to establish animal models of left bundle branch block by using three-dimensional mapping systems.This research was aimed at creating a canine left bundle branch block model b... Objective:Few studies have been conducted to establish animal models of left bundle branch block by using three-dimensional mapping systems.This research was aimed at creating a canine left bundle branch block model by using a three-dimensional mapping system.Materials and Methods:We used a three-dimensional mapping system to map and ablate the left bundle branch in beagles.Results:Ten canines underwent radiofrequency ablation,among which left bundle branch block was successfully es-tablished in eight,one experienced ventricular fibrillation,and one developed third-degree atrioventricular block.The maximum HV interval measured within the left ventricle was 29.00±2.93 ms,and the LBP-V interval at the ablation site was 20.63±2.77 ms.The LBP-V interval at the ablation target was 71.08%of the maximum HV interval.Conclusion:This three-dimensional mapping system is a reliable and effective guide for ablation of the left bundle branch in dogs. 展开更多
关键词 left bundle branch block heart failure animal model CANINE three-dimensional mapping ablation
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Three-dimensional mapping and comparative analysis of the distal human corpus cavernosum and the inflatable penile prosthesis
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作者 Tariq S Hakky Daniel Ferguson +3 位作者 Philippe E Spiess Paul Bradley Tom FLue Rafael E Carrion 《Asian Journal of Andrology》 SCIE CAS CSCD 2013年第4期567-570,I0012,共5页
The intricate anatomy of the corpus cavernosum in both the flaccid and tumescent state has not been fully elucidated. We report our experience using a three-dimensional (3D) scanner to reconstruct cadaveric casts an... The intricate anatomy of the corpus cavernosum in both the flaccid and tumescent state has not been fully elucidated. We report our experience using a three-dimensional (3D) scanner to reconstruct cadaveric casts and compare them with 3D images of two prototypes of penile prosthesis. Two different models of the Titan Coloplast inflatable penile prosthesis were analyzed using a 3D scanner. The first was the standard model and the second was a newer model with a rounder silicone tip. Two cadaveric phalluses were harvested using Smooth-Cast 300Q polyurethane molding. The molds were excised and scanned along side the penile prosthesis. 3D scans were completed and analyzed using Leios Mesh software, and GOM Inspect software. The 3D scans demonstrated the mean human corporal radii 2 mm from the distal tip to be 36.51 mm (36.01-37.0 mm), which is an obtuse angle. The standard Titan penile prosthesis spherical radius at the same level was 202.52 mm, while the new silicone tip prosthesis had a radius of 139.33 mm. 3D mapping further demonstrated the trajectory of the cavernosa appeared curvilinear and the distal ends appeared blunt. The use of cadaveric cavernosal molds in combination with the 3D scanner allowed us to accurately image the corpus cavernosum for the first time. Our findings suggest that anatomically accurate corporal tips appear to be relatively blunt and that the new Titan silicone tip penile prosthesis more closely resembles the human corporal tip. 展开更多
关键词 corpus cavernosum penile prosthesis three-dimensional analysis
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Global Mapping of Three-Dimensional Urban Structures Reveals Escalating Utilization in the Vertical Dimension and Pronounced Building Space Inequality 被引量:1
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作者 Xiaoping Liu Xinxin Wu +6 位作者 Xuecao Li Xiaocong Xu Weilin Liao Limin Jiao Zhenzhong Zeng Guangzhao Chen Xia Li 《Engineering》 2025年第4期86-99,共14页
Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significan... Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significant gap in detailed and consistent data on 3D building space structures with global coverage due to the challenges inherent in the data collection and model calibration processes.In this study,we constructed a global urban structure(GUS-3D)dataset,including building volume,height,and footprint information,at a 500 m spatial resolution using extensive satellite observation products and numerous reference building samples.Our analysis indicated that the total volume of buildings worldwide in2015 exceeded 1×10^(12)m^(3).Over the 1985 to 2015 period,we observed a slight increase in the magnitude of 3D building volume growth(i.e.,it increased from 166.02 km3 during the 1985–2000 period to 175.08km3 during the 2000–2015 period),while the expansion magnitudes of the two-dimensional(2D)building footprint(22.51×10^(3) vs 13.29×10^(3)km^(2))and urban extent(157×10^(3) vs 133.8×10^(3)km^(2))notably decreased.This trend highlights the significant increase in intensive vertical utilization of urban land.Furthermore,we identified significant heterogeneity in building space provision and inequality across cities worldwide.This inequality is particularly pronounced in many populous Asian cities,which has been overlooked in previous studies on economic inequality.The GUS-3D dataset shows great potential to deepen our understanding of the urban environment and creates new horizons for numerous 3D urban studies. 展开更多
关键词 three-dimensional Global mapping Building volume Building height Building space inequality
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A human-machine interaction method for rock discontinuities mapping by three-dimensional point clouds with noises
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作者 Qian Chen Yunfeng Ge +3 位作者 Changdong Li Huiming Tang Geng Liu Weixiang Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1646-1663,共18页
Rock discontinuities control rock mechanical behaviors and significantly influence the stability of rock masses.However,existing discontinuity mapping algorithms are susceptible to noise,and the calculation results ca... Rock discontinuities control rock mechanical behaviors and significantly influence the stability of rock masses.However,existing discontinuity mapping algorithms are susceptible to noise,and the calculation results cannot be fed back to users timely.To address this issue,we proposed a human-machine interaction(HMI)method for discontinuity mapping.Users can help the algorithm identify the noise and make real-time result judgments and parameter adjustments.For this,a regular cube was selected to illustrate the workflows:(1)point cloud was acquired using remote sensing;(2)the HMI method was employed to select reference points and angle thresholds to detect group discontinuity;(3)individual discontinuities were extracted from the group discontinuity using a density-based cluster algorithm;and(4)the orientation of each discontinuity was measured based on a plane fitting algorithm.The method was applied to a well-studied highway road cut and a complex natural slope.The consistency of the computational results with field measurements demonstrates its good accuracy,and the average error in the dip direction and dip angle for both cases was less than 3.Finally,the computational time of the proposed method was compared with two other popular algorithms,and the reduction in computational time by tens of times proves its high computational efficiency.This method provides geologists and geological engineers with a new idea to map rapidly and accurately rock structures under large amounts of noises or unclear features. 展开更多
关键词 Rock discontinuities three-dimensional(3D)point clouds Discontinuity identification Orientation measurement Human-machine interaction
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Three-dimensional mapping of the Galactic extinction curve: A new perspective on interstellar dust
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作者 Yang Huang Zhengyang Li 《The Innovation》 2025年第6期3-4,共2页
Interstellar dust plays a crucial role in astrophysics,affecting the observed properties of stars and galaxies by absorbing and scattering light.The extinction curve,which describes how this effect varies with wavelen... Interstellar dust plays a crucial role in astrophysics,affecting the observed properties of stars and galaxies by absorbing and scattering light.The extinction curve,which describes how this effect varies with wavelength,is characterized by the parameter RðVÞ,defined as the ratio of total to selective extinction. 展开更多
关键词 interstellar dust galactic extinction curve extinction curvewhich light absorption three dimensional mapping ASTROPHYSICS total extinction light scattering
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磁共振集合序列技术替代T_(2) Mapping成像对成人膝关节软骨定量分析价值
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作者 武金龙 杨慧 《实用医学影像杂志》 2026年第1期32-35,共4页
目的分析使用磁共振集合序列(MAGIC)技术替代传统T_(2) Mapping成像定量分析成人膝关节关节软骨的临床价值。方法收集本院体检受试者36例,分为3组21~30岁,11例;31~40岁,10例;41~50岁,15例,分别行MAGIC和T_(2) Mapping扫描,比较软骨MAGIC... 目的分析使用磁共振集合序列(MAGIC)技术替代传统T_(2) Mapping成像定量分析成人膝关节关节软骨的临床价值。方法收集本院体检受试者36例,分为3组21~30岁,11例;31~40岁,10例;41~50岁,15例,分别行MAGIC和T_(2) Mapping扫描,比较软骨MAGIC T_(2)值与T_(2) Mapping T_(2)值是否存在差异。比较各年龄段胫骨内侧平台软骨、胫骨外侧平台软骨、股骨内侧髁软骨、股骨外侧髁软骨、髌骨表面软骨差异。结果MAGIC与T_(2) Mapping 2种方法分别对膝关节的不同部位关节软骨定量T_(2)值分析,2种方法对比差异无统计学意义(P>0.05)。41~50岁与21~30岁关节软骨厚度差异有统计学意义。利用MAGIC技术发现41~50岁与21~30岁各部位关节软骨T_(2)测值差异有统计学意义(P<0.05)。结论MAGIC技术能代替传统T_(2) Mapping成像方法定量分析成人膝关节软骨。 展开更多
关键词 膝关节 软骨 成人 磁共振集合序列 T_(2)mapping 定量分析
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Native T1 mapping值显著延长心脏纤维瘤一例
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作者 文涛 张辉 +3 位作者 甘铁军 胡万均 李世兰 张静 《磁共振成像》 北大核心 2026年第1期120-122,共3页
本研究为回顾性研究,遵守《赫尔辛基宣言》,并经兰州大学第二医院伦理委员会审核批准,免除受试者知情同意,批准文号:2025A-547。患儿,女,2月8天,因“发现心脏肿瘤2月”于2024年11月就诊于我院,患儿于2个月前出生后外院检查提示左心室肿... 本研究为回顾性研究,遵守《赫尔辛基宣言》,并经兰州大学第二医院伦理委员会审核批准,免除受试者知情同意,批准文号:2025A-547。患儿,女,2月8天,因“发现心脏肿瘤2月”于2024年11月就诊于我院,患儿于2个月前出生后外院检查提示左心室肿瘤,未予特殊诊治,现为进一步明确诊治收住我院心脏外科。患儿足月(38+6周)、顺产、无心脏肿瘤家族史。查体:心前区无隆起,心界不大,心音有力、律齐,胸骨左缘第2~3肋间可闻及3/6及吹风样杂音,静息血氧饱和度100%。 展开更多
关键词 心脏肿瘤 心脏纤维瘤 多模态磁共振成像 心脏磁共振 Native T1 mapping
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T2 Mapping联合DWI序列评估直肠癌脉管侵犯价值研究
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作者 李茜玮 陈安良 +2 位作者 王楠 林良杰 刘爱连 《中国CT和MRI杂志》 2026年第1期149-152,共4页
目的探讨T2 mapping与DWI序列预测直肠癌脉管侵犯的价值。方法回顾性分析经本院行3.0T MRI扫描且经术后病理证实的直肠癌脉管侵犯13例,脉管非侵犯20例,2名观察者分别于瘤体显示最大层面参考增强动脉期图像及DWI图像于T2 mapping及ADC图... 目的探讨T2 mapping与DWI序列预测直肠癌脉管侵犯的价值。方法回顾性分析经本院行3.0T MRI扫描且经术后病理证实的直肠癌脉管侵犯13例,脉管非侵犯20例,2名观察者分别于瘤体显示最大层面参考增强动脉期图像及DWI图像于T2 mapping及ADC图像上测量病灶T2值及ADC值。采用组内相关系数(intraclass correlation cofficient,ICC)评估两名观察者测量参数值的一致性。采用独立样本t检验或Mann-Whitney U检验分析两组病例各参数的差异。采用Logistic回归计算有统计学差异的参数联合评估直肠癌LVI的预测值。采用ROC曲线评估有差异参数单独或联合的诊断效能,并利用De-Long检验比较各ROC曲线间的差异。采用Pearson相关性检验分析两参数值的相关性。结果2名观察者测量T2值及ADC值一致性好(ICC>0.75)。脉管侵犯组的T2值及ADC值低于非脉管侵犯组(77.15±6.95ms、0.69±0.15mm^(2)/s vs 87.04±7.75ms、0.90±0.21 mm^(2)/s,P<0.05)。ADC值与ADC-T2联合鉴别两组疾病的AUC值比较差异具有统计学意义(P=0.036)。结论T2 mapping和DWI序列可预测直肠癌脉管侵犯,两序列联合效能提升,因此T2值与ADC值联合可为临床诊疗直肠癌脉管侵犯提供参考信息。 展开更多
关键词 直肠癌 脉管侵犯 磁共振成像 T2 mapping成像 弥散加权成像
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MRI T2 Mapping定量参数与乳腺癌临床分期的关系研究
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作者 马书敏 岳志领 +4 位作者 李莹 许彩红 王静静 王娜 李建丽 《中国CT和MRI杂志》 2026年第3期76-79,共4页
目的分析磁共振成像(MRI)T2 mapping定量参数与乳腺癌临床分期的关系。方法回顾性分析2023年8月~2024年8月邯郸市中心医院收治的86例乳腺癌患者的临床资料,根据病理结果分为中早期组(54例)和晚期组(32例)。比较两组患者基线资料、MRI图... 目的分析磁共振成像(MRI)T2 mapping定量参数与乳腺癌临床分期的关系。方法回顾性分析2023年8月~2024年8月邯郸市中心医院收治的86例乳腺癌患者的临床资料,根据病理结果分为中早期组(54例)和晚期组(32例)。比较两组患者基线资料、MRI图像特征(形态、边缘、强化方式及纤维腺体类型)及T2 mapping定量参数(10th位数、90th位数、熵值及平均值)。绘制受试者工作特征曲线,以曲线下面积(AUC)评估T2 mapping定量参数对晚期乳腺癌的诊断效能。使用Pearson法分析T2 mapping定量参数与晚期乳腺癌的关系。结果两组患者基线资料、形态、边缘、强化方式、纤维腺体类型、90th位数及熵值比较,差异无统计学意义(P>0.05)。晚期组10th位数、平均值小于中早期组(P<0.05)。ROC曲线显示,T2 mapping定量参数中的10th位数、平均值诊断晚期乳腺癌的AUC分别为0.826、0.870,二者联合(并联)诊断晚期乳腺癌的AUC为0.899(95%CI:0.815~0.954),敏感度为87.50%,特异度为83.33%,联合诊断AUC高于单独指标(Z=6.997、9.274,均P<0.05)。Pearson法分析结果显示,T2 mapping定量参数中的10th位数、平均值与晚期乳腺癌呈明显负相关(P<0.05)。结论MRI T2 mapping定量参数中的10th位数、平均值与晚期乳腺癌呈明显相关性,可用于评估乳腺癌临床分期,联合检测有助于提高诊断准确性。 展开更多
关键词 磁共振成像 T2mapping定量参数 乳腺癌 临床分期 相关性
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T1 Mapping联合扩散加权成像构建多模态预测模型在乳腺肿块良恶性鉴别中的应用研究
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作者 吴小敏 赖燕琴 +2 位作者 廖雪燕 罗珊 林丹丹 《生物医学工程学进展》 2026年第1期63-68,共6页
目的评估T1 Mapping联合扩散加权成像(diffusion-weighted imaging,DWI)在乳腺肿块良恶性鉴别中的诊断价值,并分析其与Ki-67表达的相关性。方法回顾性纳入96例经病理证实的乳腺肿块患者,比较T1值、T1+值、△T1%、T2值及表观弥散系数(app... 目的评估T1 Mapping联合扩散加权成像(diffusion-weighted imaging,DWI)在乳腺肿块良恶性鉴别中的诊断价值,并分析其与Ki-67表达的相关性。方法回顾性纳入96例经病理证实的乳腺肿块患者,比较T1值、T1+值、△T1%、T2值及表观弥散系数(apparent diffusion coefficient,ADC)的差异,采用Logistic回归构建联合模型并进受试者操作特征(receiver operating characteristic,ROC)曲线分析,同时评估MRI参数与Ki-67的Spearman相关性。结果恶性肿块T1值、T1+值及△T1%均显著高于良性肿块,ADC显著低于良性(均P<0.05)。多因素分析显示△T1%与ADC为独立预测因子。联合模型的曲线下面积(area under the curve,AUC)为0.941,优于各单项MRI定量指标。Ki-67高表达组△T1%升高、ADC降低(均P<0.05),且△T1%与Ki-67呈正相关(r=0.462),ADC与Ki-67呈负相关(r=−0.518)。结论T1 Mapping联合DWI可显著提高乳腺肿块良恶性的鉴别效能,△T1%与ADC具有重要的诊断价值,并可反映肿瘤的增殖活性。 展开更多
关键词 T1 mapping 扩散加权成像 乳腺肿块 表观弥散系数 Ki-67
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多b值DWI与T2 mapping定量技术诊断前列腺癌与前列腺增生结节价值研究
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作者 王旭 陈婷 +1 位作者 王姗 谢晓平 《哈尔滨医药》 2026年第1期4-7,共4页
目的研究多b值扩散加权序列(diffusion-weighted sequence,DWI)与T2 mapping序列定量值鉴别前列腺癌(Prostate cancer,PCa)与前列腺增生(Benign Prostatic Hyperplasia,BPH)的诊断价值。方法回顾性分析在南通大学附属江阴医院放射科MRI... 目的研究多b值扩散加权序列(diffusion-weighted sequence,DWI)与T2 mapping序列定量值鉴别前列腺癌(Prostate cancer,PCa)与前列腺增生(Benign Prostatic Hyperplasia,BPH)的诊断价值。方法回顾性分析在南通大学附属江阴医院放射科MRI检查并获得病理证实PCa患者67例、BPH患者66例影像资料。两组病例分别测得b=1000、2000s/mm^(2)扩散加权成像(DWI)的ADC值及T2 mapping值,比较两组间不同b值ADC值和T2值差异,受试者工作特征(ROC)曲线分析各参数及ADC_(2000)-T2联合模型的诊断效能。结果PCa组ADC_(1000)值、ADC_(2000)值、T2值均低于BPH组,差异有统计学意义(P<0.01)。ADC_(1000)值、ADC_(2000)值、T2值以及ADC_(2000)-T2联合模型鉴别PCa与BPH的AUC值分别为0.80、0.83、0.89及0.92。ADC_(2000)-T2 mapping联合模型诊断效能优于单独ADC_(1000)值、ADC_(2000)值,差异有统计学意义(P<0.01)。结论DWI、T2 mapping序列定量值诊断PCa与BPH有较好的鉴别价值,而且联合高b值DWI、T2 mapping联合模型诊断效能有所提升,能够为临床诊断PCa提供较好的诊断依据。 展开更多
关键词 前列腺癌 前列腺增生 扩散加权序列 T2 mapping序列
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A Comprehensive Literature Review of AI-Driven Application Mapping and Scheduling Techniques for Network-on-Chip Systems
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作者 Naveed Ahmad Muhammad Kaleem +5 位作者 Mourad Elloumi Muhammad Azhar Mushtaq Ahlem Fatnassi Mohd Fazil Anas Bilal Abdulbasit A.Darem 《Computer Modeling in Engineering & Sciences》 2026年第1期118-155,共38页
Network-on-Chip(NoC)systems are progressively deployed in connecting massively parallel megacore systems in the new computing architecture.As a result,application mapping has become an important aspect of performance ... Network-on-Chip(NoC)systems are progressively deployed in connecting massively parallel megacore systems in the new computing architecture.As a result,application mapping has become an important aspect of performance and scalability,as current trends require the distribution of computation across network nodes/points.In this paper,we survey a large number of mapping and scheduling techniques designed for NoC architectures.This time,we concentrated on 3D systems.We take a systematic literature review approach to analyze existing methods across static,dynamic,hybrid,and machine-learning-based approaches,alongside preliminary AI-based dynamic models in recent works.We classify them into several main aspects covering power-aware mapping,fault tolerance,load-balancing,and adaptive for dynamic workloads.Also,we assess the efficacy of each method against performance parameters,such as latency,throughput,response time,and error rate.Key challenges,including energy efficiency,real-time adaptability,and reinforcement learning integration,are highlighted as well.To the best of our knowledge,this is one of the recent reviews that identifies both traditional and AI-based algorithms for mapping over a modern NoC,and opens research challenges.Finally,we provide directions for future work toward improved adaptability and scalability via lightweight learned models and hierarchical mapping frameworks. 展开更多
关键词 Application mapping mapping techniques NETWORK-ON-CHIP system on chip optimisation
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Ecological Three-Dimensional Cultivation and Digital Development Model of Xinjiashan Specialty Coffee Base
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作者 Jiangnan WANG Yulian MA +3 位作者 Tingting YANG Caide DUAN Jin'e LI Guangxue YANG 《Plant Diseases and Pests》 2026年第1期22-25,29,共5页
Under the strategic framework of rural revitalization and agricultural modernization, Xinjiashan Specialty Coffee Base, located in Zaotang Village, Lujiang Town, Longyang District, Baoshan City, has been proactively i... Under the strategic framework of rural revitalization and agricultural modernization, Xinjiashan Specialty Coffee Base, located in Zaotang Village, Lujiang Town, Longyang District, Baoshan City, has been proactively investigating innovative models for agricultural development. Through extensive communication and collaboration, this base has established close partnerships with research institutions including Kunming University of Science and Technology, Baoshan University, and Yunnan Academy of Agricultural Sciences, with a commitment to thoroughly exploring the potential for resource recycling and ecological complementarity. An innovative four-in-one three-dimensional integrated planting system incorporating "coffee, bananas, green manure, and bees" has been implemented. Concurrently, technological and digital management strategies have been comprehensively integrated to improve planting efficiency. Under this model, the proportion of specialty coffee attains 71%, and the per-unit yield is 17% greater than that of the conventional planting model. This approach not only substantially enhances economic returns but also promotes the integrated development of ecological and social benefits, offering a valuable practical example and experiential reference for the specialty and sustainable advancement of the coffee industry in comparable regions. 展开更多
关键词 COFFEE three-dimensional planting DIGITALIZATION Ecological cycle Xinjiashan
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3D Spectrum Mapping and Reconstruction Under Multi-Radiation Source Scenarios
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作者 Wang Jie Lin Zhipeng +5 位作者 Zhu Qiuming Wu Qihui Lan Tianxu Zhao Yi Bai Yunpeng Zhong Weizhi 《China Communications》 2026年第2期20-34,共15页
Spectrum map construction,which is crucial in cognitive radio(CR)system,visualizes the invisible space of the electromagnetic spectrum for spectrum-resource management and allocation.Traditional reconstruction methods... Spectrum map construction,which is crucial in cognitive radio(CR)system,visualizes the invisible space of the electromagnetic spectrum for spectrum-resource management and allocation.Traditional reconstruction methods are generally for twodimensional(2D)spectrum map and driven by abundant sampling data.In this paper,we propose a data-model-knowledge-driven reconstruction scheme to construct the three-dimensional(3D)spectrum map under multi-radiation source scenarios.We firstly design a maximum and minimum path loss difference(MMPLD)clustering algorithm to detect the number of radiation sources in a 3D space.Then,we develop a joint location-power estimation method based on the heuristic population evolutionary optimization algorithm.Considering the variation of electromagnetic environment,we self-learn the path loss(PL)model based on the sampling data.Finally,the 3D spectrum is reconstructed according to the self-learned PL model and the extracted knowledge of radiation sources.Simulations show that the proposed 3D spectrum map reconstruction scheme not only has splendid adaptability to the environment,but also achieves high spectrum construction accuracy even when the sampling rate is very low. 展开更多
关键词 cognitive radio map reconstruction path loss model radiation source 3D spectrum map
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基于双参数MRI弥散加权成像和T_(2)mapping成像对前列腺癌的诊断价值
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作者 王永胜 陈文静 +1 位作者 何俊林 马财 《影像研究与医学应用》 2026年第5期28-31,36,共5页
目的:探讨基于双参数MRI(bpMRI)的表观弥散系数(ADC)值、T_(2)mapping值及临床指标对前列腺癌(PCa)的诊断价值。方法:回顾性分析2022年11月—2025年1月上海市金山区亭林医院收治的93例疑似PCa的患者bpMRI图像,完成前列腺影像报告和数据... 目的:探讨基于双参数MRI(bpMRI)的表观弥散系数(ADC)值、T_(2)mapping值及临床指标对前列腺癌(PCa)的诊断价值。方法:回顾性分析2022年11月—2025年1月上海市金山区亭林医院收治的93例疑似PCa的患者bpMRI图像,完成前列腺影像报告和数据系统(PI-RADS)评分,并测量病灶的ADC值、T_(2)mapping值,记录患者年龄、总前列腺特异性抗原(t-PSA)、游离前列腺特异性抗原(f-PSA)、f-PSA/t-PSA(f/t)值及PSA密度值等临床指标。采用Logistic回归分析临床指标、ADC值及T_(2)mapping值与PCa的关系,构建基于双参数、ADC值及T_(2)mapping值的联合诊断模型,通过受试者工作特征(ROC)曲线评估ADC值、T_(2)mapping值、双参数PI-RADS评分及其分别联合ADC值或T_(2)mapping值的诊断效能。结果:非PCa与PCa患者的PSA密度、ADC值、T_(2)mapping值比较,差异有统计学意义(P<0.05)。ADC值与T_(2)mapping值诊断PCa的效能均较高(P<0.05),双参数PI-RADS评分、联合ADC值、联合T_(2)mapping值诊断外周带PCa的曲线下面积(AUC)分别为0.883、0.918和0.902;诊断移行带PCa的AUC分别为0.798、0.810和0.817。结论:对于临床指标提示恶性可能的前列腺疾病患者,bpMRI联合ADC值与T_(2)mapping值可显著提高PCa的诊断效能。 展开更多
关键词 双参数磁共振成像 表观弥散系数 T_(2)mapping 临床指标 前列腺癌
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Research on dynamic three-dimensional terrain correction methods of quantitative inversion for airborne gamma-ray spectrometer
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作者 He-Xi Wu Wei-Cheng Li +6 位作者 Rui Qiu Chao Xiong Yi-Ming Lyu Yi-Qiang Xing De-Hao Zhang Zong-Shuo Tao Yang Wang 《Nuclear Science and Techniques》 2026年第5期199-214,共16页
Aerial surveys are dynamic and continuous processes,and there are different height distributions of the ground in the measurement area,which leads to problems such as overlapping measurement areas and inaccurate altit... Aerial surveys are dynamic and continuous processes,and there are different height distributions of the ground in the measurement area,which leads to problems such as overlapping measurement areas and inaccurate altitude correction during the survey process.Commonly used terrain correction methods are based on the concept of finite elementization of ground surface radioactive sources,using GPS coordinates,radar altitude,and ground elevation distribution information from aerial surveys,combined with the sourceless efficiency calibration method to construct a response matrix,which is then inverted for surface nuclide content.However,most of the sourceless efficiency calibration methods used are numerical calculations that consider the body detector as a point detector and do not consider the changes in intrinsic detection efficiency under different incident directions of gamma rays.Therefore,when the altitude of the measurement area varies significantly or the flight altitude of the aerial survey is relatively low,such sourceless efficiency calibration method calculations tend to have a large bias,which affects the accuracy of the terrain correction.To address the above problems,this study employs a novel sourceless efficiency calibration method based on the Boolean operation of the ray deposition process and simplifies the traditional body source measurement model to a surface source measurement model to achieve fast and accurate efficiency calibration.Then,through the discretization of the measurement process,the static measurement process is superposed as equivalent to the dynamic measurement process,and the dynamic measurement response matrix is built and optimized based on the calibration method.Finally,the PSO-MLEM algorithm was used to solve the dynamic measurement response matrix to achieve dynamic terrain correction of aerial survey data.Analysis of the Baiyun'ebo test area revealed that,after applying dynamic terrain correction,the inverted anomalies in uranium(eU),thorium(eTh),and potassium(K)concentrations were closer to ground measurements(within 5.72%-30.79%)and exhibited clearer anomaly boundaries compared to traditional height-based corrections.However,owing to the inherent statistical fluctuations and characteristics of matrix inversion,higher measurement values tend to absorb lower ones,potentially enlarging the anomalous regions.Nevertheless,the highanomaly regions after inversion largely coincided with the ground truth validation,demonstrating that the proposed method can effectively correct airborne gamma spectrometry data. 展开更多
关键词 Airborne gamma-ray spectrum Dynamic three-dimensional Terrain correction
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Research Progress on Patient Journey Mapping in the Field of Nursing
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作者 Fei Chen 《Journal of Clinical and Nursing Research》 2026年第2期162-168,共7页
In recent years, improving patients’ medical experience has become increasingly prominent in medical activities, and patient experience has become the core of medical service models. As an emerging visualization tool... In recent years, improving patients’ medical experience has become increasingly prominent in medical activities, and patient experience has become the core of medical service models. As an emerging visualization tool for exploring patient experience, patient journey mapping has been increasingly applied in the field of medical and health services, with unique advantages in exploring patient experience. This study reviews the overview, content and types, application and effects in the nursing field, and presentation methods of results of patient journey mapping, aiming to provide reference for improving patient experience. 展开更多
关键词 Patient journey mapping Patient experience Nursing management
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Design of a Patrol and Security Robot with Semantic Mapping and Obstacle Avoidance System Using RGB-D Camera and LiDAR
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作者 Shu-Yin Chiang Shin-En Huang 《Computers, Materials & Continua》 2026年第4期1735-1753,共19页
This paper presents an intelligent patrol and security robot integrating 2D LiDAR and RGB-D vision sensors to achieve semantic simultaneous localization and mapping(SLAM),real-time object recognition,and dynamic obsta... This paper presents an intelligent patrol and security robot integrating 2D LiDAR and RGB-D vision sensors to achieve semantic simultaneous localization and mapping(SLAM),real-time object recognition,and dynamic obstacle avoidance.The system employs the YOLOv7 deep-learning framework for semantic detection and SLAM for localization and mapping,fusing geometric and visual data to build a high-fidelity 2D semantic map.This map enables the robot to identify and project object information for improved situational awareness.Experimental results show that object recognition reached 95.4%mAP@0.5.Semantic completeness increased from 68.7%(single view)to 94.1%(multi-view)with an average position error of 3.1 cm.During navigation,the robot achieved 98.0%reliability,avoided moving obstacles in 90.0%of encounters,and replanned paths in 0.42 s on average.The integration of LiDAR-based SLAMwith deep-learning–driven semantic perception establishes a robust foundation for intelligent,adaptive,and safe robotic navigation in dynamic environments. 展开更多
关键词 RGB-D semantic mapping object recognition obstacle avoidance security robot
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Accurate closed-form flutter eigensolutions of three-dimensional composite laminates with shear deformation
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作者 Dezhuang PAN Yufeng XING 《Chinese Journal of Aeronautics》 2026年第1期230-246,共17页
According to the Mindlin plate theory and the first-order piston theory,this work obtains accurate closed-form eigensolutions for the flutter problem of three-dimensional(3D)rectangular laminated panels.The governing ... According to the Mindlin plate theory and the first-order piston theory,this work obtains accurate closed-form eigensolutions for the flutter problem of three-dimensional(3D)rectangular laminated panels.The governing differential equations are derived by the Hamilton's variational principle,and then solved by the iterative Separation-of-Variable(i SOV)method,which are applicable to arbitrary combinations of homogeneous Boundary Conditions(BCs).However,only the simply-support,clamped and cantilever panels are considered in this work for the sake of clarity.With the closed-form eigensolutions,the flutter frequency,flutter mode and flutter boundary are presented,and the effect of shear deformation and aerodynamic damping on flutter frequencies is investigated.Besides,the relation between panel energy and the work of aerodynamic load is discussed.The numerical comparisons reveal the following.(A)The flutter eigenvalues obtained by the present method are accurate,validated by the Finite Element Method(FEM)and the Galerkin method.(B)When the span-chord ratio is larger than 3,simplifying a 3D panel to 2D(two-dimensional)panel is reasonable and the relative differences of the flutter points predicted by the two models are less than one percent.(C)The reciprocal relationship between the mechanical energy of the panel and the work done by aerodynamic load is verified by using the present flutter eigenvalues and modes,further indicating the high accuracy of the present solutions.(D)The coupling of shear deformation and aerodynamic damping prevents frequency coalescing. 展开更多
关键词 Closed-form eigensolutions The first-order piston theory The Mindlin plate theory three-dimensional panel flutter Separation-of-variable method
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