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
目的探讨心脏磁共振组织追踪(cardiac magnetic resonance tissue tracing,CMR-TT)技术及T1 mapping技术在2型糖尿病(type 2 diabetes mellitus,T2DM)患者心肌损伤评估中的应用价值。材料与方法前瞻性收集2023年12月至2025年4月在我院...目的探讨心脏磁共振组织追踪(cardiac magnetic resonance tissue tracing,CMR-TT)技术及T1 mapping技术在2型糖尿病(type 2 diabetes mellitus,T2DM)患者心肌损伤评估中的应用价值。材料与方法前瞻性收集2023年12月至2025年4月在我院进行心脏磁共振检查的T2DM患者64例,健康对照(healthy controls,HC)32例。所有心脏磁共振图像数据导入专用软件进行分析,获取全心心肌应变参数、双心室功能参数以及左心室T1 mapping参数,采用t检验,Mann-Whitney U检验及卡方检验对两组间上述参数进行比较,采用Pearson及Spearman相关性分析心肌结构、功能与心肌应变的关联。结果T2DM组左心室心肌质量指数(left ventricular myocardial mass index,LVMI)、左心室重塑指数(left ventricular remodeling index,LVRI)增加(均P<0.001),左心室全局纵向应变(global longitudinal peak strain in the left ventricle,LV GLS)、右心室全局纵向应变降低(均P<0.05),T2DM组周向左心室收缩期峰值应变率(peak systolic strain rate of the left ventricle,LV PSSR)、纵向LV PSSR及左心室舒张期峰值应变率(diastolic peak strain rate of the left ventricle,LV PDSR)绝对值均降低(均P<0.019)。T2DM患者左心房/右心房(leftatrium/rightatrium,LA/RA)储存应变、LA/RA导管应变均降低(均P<0.001)。T2DM患者的细胞外容积(extracellular volume,ECV)较HC组升高(P<0.001)。双心室射血分数、收缩末期容积指数与双心室应变功能均相关(均P<0.003)。LVMI与左心室全局径向应变(global radial strain of the left ventricle,LV GRS)、左心室全局周向应变(global circumferential strain of the left ventricle,LV GCS)、LV GLS、周向LV PSSR、纵向LV PSSR、径向LV PDSR、周向LV PDSR、纵向LV PDSR相关(均P<0.021)。左心室舒张末期容积指数与LV GCS、LV GLS、周向LV PSSR、纵向LV PSSR、周向LV PDSR相关(均P<0.044)。右心室舒张末期容积指数与右心室全局周向应变相关(r=0.331,P=0.007)。LVRI与LV GLS及纵向LV PDSR相关(均P<0.01),且与径向LV PSSR弱相关(r=0.266,P=0.034)。结论T2DM患者全心心肌应变较对照组降低,ECV值升高,双心室心肌结构、功能与心肌应变相互关联,CMR-TT及T1 mapping技术可以有效检测糖尿病心肌损伤。展开更多
目的通过磁共振R2*mapping技术示踪及动态监测NSCLC裸鼠模型给药后不同时间点R2*值的变化趋势,阐明R2*mapping在评价F/A-PLGA@DOX/SPIO纳米载药体系在肿瘤成像中的应用价值及影像学基础。方法成功构建NSCLC裸鼠移植瘤模型24只,随机分为G...目的通过磁共振R2*mapping技术示踪及动态监测NSCLC裸鼠模型给药后不同时间点R2*值的变化趋势,阐明R2*mapping在评价F/A-PLGA@DOX/SPIO纳米载药体系在肿瘤成像中的应用价值及影像学基础。方法成功构建NSCLC裸鼠移植瘤模型24只,随机分为G1、G2两组,每组12只。分别尾静脉注射单纯SPIO以及F/A-PLGA@DOX/SPIO纳米载药体系,并采用1.5 T MR和动物专用小鼠线圈对建模成功荷瘤裸鼠皮下移植瘤模型进行R2*扫描获得肿瘤区域R2*值。实验结束后全部肿瘤组织及肝脏、脾脏普鲁士蓝染色。结果G2组每个时间点的R2*值均高于G1组(P<0.05)。相对于G1组,G2组肿瘤R2*值在早期上升趋势明显,且在给药后60h时明显高于G1组(P<0.05)。G1组排泄期较G2组明显提前。普鲁士蓝染色结果显示,G2组肿瘤的蓝色铁沉积高于SPIO组,而肝脏、脾脏组织的蓝色铁沉积低于G1。结论R2*值与肿瘤组织内的SPIO含量存在较高敏感性,R2*mapping技术提供了一种SPIO的肿瘤示踪成像方法。展开更多
T6 et al presented a bilinear-map-based traitor tracing scheme（TSZ scheme） with revocation, but it is a symmetric scheme because it does not provide non-repudiation. In this paper, an improved TSZ scheme was propose...T6 et al presented a bilinear-map-based traitor tracing scheme（TSZ scheme） with revocation, but it is a symmetric scheme because it does not provide non-repudiation. In this paper, an improved TSZ scheme was proposed by using oblivious polynomial evaluation （OPE） protocol and service parameters. Under the recondition of general sameness capabilities of both TSZ and improved TSZ scheme, the new scheme adds some advantages such as providing multi-service capability, user＇s non-repudiation and data provider＇s no-framing innocent users. Furthermore, it is also proved to be semantically secure under the decisional bilinear Diffie-Hellman （DBDH problem） assumption.展开更多
Digital crime inflicts immense damage to users and systems and now it has reached a level of sophistication that makes it difficult to track its sources or origins especially with the advancements in modern computers,...Digital crime inflicts immense damage to users and systems and now it has reached a level of sophistication that makes it difficult to track its sources or origins especially with the advancements in modern computers, networks and the availability of diverse digital devices. Forensic has an important role to facilitate investigations of illegal activities and inappropriate behaviors using scientific methodologies, techniques and investigation frameworks. Digital forensic is developed to investigate any digital devices in the detection of crime. This paper emphasized on the research of traceability aspects in digital forensic investigation process. This includes discovering of complex and huge volume of evidence and connecting meaningful relationships between them. The aim of this paper is to derive a traceability index as a useful indicator in measuring the accuracy and completeness of discovering the evidence. This index is demonstrated through a model (TraceMap) to facilitate the investigator in tracing and mapping the evidence in order to identify the origin of the crime or incident. In this paper, tracing rate, mapping rate and offender identification rate are used to present the level of tracing ability, mapping ability and identifying the offender ability respectively. This research has a high potential of being expanded into other research areas such as in digital evidence presentation.展开更多
基金supported by the Special Fund for Basic Research on Scientific Instruments of the National Natural Science Foundation of China(Grant No.4182780021)Emeishan-Hanyuan Highway ProgramTaihang Mountain Highway Program。
文摘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.
文摘目的探讨心脏磁共振组织追踪(cardiac magnetic resonance tissue tracing,CMR-TT)技术及T1 mapping技术在2型糖尿病(type 2 diabetes mellitus,T2DM)患者心肌损伤评估中的应用价值。材料与方法前瞻性收集2023年12月至2025年4月在我院进行心脏磁共振检查的T2DM患者64例,健康对照(healthy controls,HC)32例。所有心脏磁共振图像数据导入专用软件进行分析,获取全心心肌应变参数、双心室功能参数以及左心室T1 mapping参数,采用t检验,Mann-Whitney U检验及卡方检验对两组间上述参数进行比较,采用Pearson及Spearman相关性分析心肌结构、功能与心肌应变的关联。结果T2DM组左心室心肌质量指数(left ventricular myocardial mass index,LVMI)、左心室重塑指数(left ventricular remodeling index,LVRI)增加(均P<0.001),左心室全局纵向应变(global longitudinal peak strain in the left ventricle,LV GLS)、右心室全局纵向应变降低(均P<0.05),T2DM组周向左心室收缩期峰值应变率(peak systolic strain rate of the left ventricle,LV PSSR)、纵向LV PSSR及左心室舒张期峰值应变率(diastolic peak strain rate of the left ventricle,LV PDSR)绝对值均降低(均P<0.019)。T2DM患者左心房/右心房(leftatrium/rightatrium,LA/RA)储存应变、LA/RA导管应变均降低(均P<0.001)。T2DM患者的细胞外容积(extracellular volume,ECV)较HC组升高(P<0.001)。双心室射血分数、收缩末期容积指数与双心室应变功能均相关(均P<0.003)。LVMI与左心室全局径向应变(global radial strain of the left ventricle,LV GRS)、左心室全局周向应变(global circumferential strain of the left ventricle,LV GCS)、LV GLS、周向LV PSSR、纵向LV PSSR、径向LV PDSR、周向LV PDSR、纵向LV PDSR相关(均P<0.021)。左心室舒张末期容积指数与LV GCS、LV GLS、周向LV PSSR、纵向LV PSSR、周向LV PDSR相关(均P<0.044)。右心室舒张末期容积指数与右心室全局周向应变相关(r=0.331,P=0.007)。LVRI与LV GLS及纵向LV PDSR相关(均P<0.01),且与径向LV PSSR弱相关(r=0.266,P=0.034)。结论T2DM患者全心心肌应变较对照组降低,ECV值升高,双心室心肌结构、功能与心肌应变相互关联,CMR-TT及T1 mapping技术可以有效检测糖尿病心肌损伤。
文摘目的通过磁共振R2*mapping技术示踪及动态监测NSCLC裸鼠模型给药后不同时间点R2*值的变化趋势,阐明R2*mapping在评价F/A-PLGA@DOX/SPIO纳米载药体系在肿瘤成像中的应用价值及影像学基础。方法成功构建NSCLC裸鼠移植瘤模型24只,随机分为G1、G2两组,每组12只。分别尾静脉注射单纯SPIO以及F/A-PLGA@DOX/SPIO纳米载药体系,并采用1.5 T MR和动物专用小鼠线圈对建模成功荷瘤裸鼠皮下移植瘤模型进行R2*扫描获得肿瘤区域R2*值。实验结束后全部肿瘤组织及肝脏、脾脏普鲁士蓝染色。结果G2组每个时间点的R2*值均高于G1组(P<0.05)。相对于G1组,G2组肿瘤R2*值在早期上升趋势明显,且在给药后60h时明显高于G1组(P<0.05)。G1组排泄期较G2组明显提前。普鲁士蓝染色结果显示,G2组肿瘤的蓝色铁沉积高于SPIO组,而肝脏、脾脏组织的蓝色铁沉积低于G1。结论R2*值与肿瘤组织内的SPIO含量存在较高敏感性,R2*mapping技术提供了一种SPIO的肿瘤示踪成像方法。
基金Supported by the National Natural Science Foundation of China (60372046)
文摘T6 et al presented a bilinear-map-based traitor tracing scheme（TSZ scheme） with revocation, but it is a symmetric scheme because it does not provide non-repudiation. In this paper, an improved TSZ scheme was proposed by using oblivious polynomial evaluation （OPE） protocol and service parameters. Under the recondition of general sameness capabilities of both TSZ and improved TSZ scheme, the new scheme adds some advantages such as providing multi-service capability, user＇s non-repudiation and data provider＇s no-framing innocent users. Furthermore, it is also proved to be semantically secure under the decisional bilinear Diffie-Hellman （DBDH problem） assumption.
文摘Digital crime inflicts immense damage to users and systems and now it has reached a level of sophistication that makes it difficult to track its sources or origins especially with the advancements in modern computers, networks and the availability of diverse digital devices. Forensic has an important role to facilitate investigations of illegal activities and inappropriate behaviors using scientific methodologies, techniques and investigation frameworks. Digital forensic is developed to investigate any digital devices in the detection of crime. This paper emphasized on the research of traceability aspects in digital forensic investigation process. This includes discovering of complex and huge volume of evidence and connecting meaningful relationships between them. The aim of this paper is to derive a traceability index as a useful indicator in measuring the accuracy and completeness of discovering the evidence. This index is demonstrated through a model (TraceMap) to facilitate the investigator in tracing and mapping the evidence in order to identify the origin of the crime or incident. In this paper, tracing rate, mapping rate and offender identification rate are used to present the level of tracing ability, mapping ability and identifying the offender ability respectively. This research has a high potential of being expanded into other research areas such as in digital evidence presentation.
