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Enhanced CT and CT virtual endoscopy in diagnosis of heterotopic pancreas 被引量:28
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作者 Dan Wang Xiao-Er Wei Lei Yan Yu-Zhen Zhang Wen-Bin Li 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第33期3850-3855,共6页
AIM:To improve the diagnosis of heterotopic pancreas by the use of contrastenhanced computed tomography(CT)imaging and CT virtual endoscopy(CTVE).METHODS:A total of six patients with heterotopic pancreas,as confirmed ... AIM:To improve the diagnosis of heterotopic pancreas by the use of contrastenhanced computed tomography(CT)imaging and CT virtual endoscopy(CTVE).METHODS:A total of six patients with heterotopic pancreas,as confirmed by clinical pathology and immunohistochemistry in the Sixth Affiliated People's Hospital of Shanghai Jiao Tong University,Shanghai,China,were included.Nonenhanced CT and enhanced CT scanning were performed,and the resulting images were reviewed and analyzed using threedimensional postprocessing software,including CTVE.RESULTS:Four males and two females were enrolled.Several heterotopic pancreas sites were involved;three occurred in the stomach,including the gastric antrum(n =2)and lesser curvature(n=1),and two were in the duodenal bulb.Only one case of heterotopic pancreas lesion occurred in the mesentery.Four cases had a solid yet soft tissue density that had a homogeneous pattern when viewed by enhanced CT.Additionally,their CT values were similar to that of the pancreas.The ducts of the heterotopic pancreas tissue,one of the characteristic CT features of heterotopic pancreas tissue,were detected in the CT images of two patients.CTVE images showed normal mucosa around the tissue,which is also an important indicator of a heterotopic pancreas.However,none of the CTVE images showed the typical signs of central dimpling or umbilication.CONCLUSION:CT,enhanced CT and CTVE techniques provide useful information about the location,growth pattern,vascularity,and condition of the gastrointestinal wall around heterotopic pancreatic tissue. 展开更多
关键词 Heterotopic pancreas Computed tomography Contrast enhancement Computed tomography virtual endoscopy
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Diagnosis of Leukemia Disease Based on Enhanced Virtual Neural Network 被引量:1
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作者 K.Muthumayil S.Manikandan +3 位作者 S.Srinivasan JoséEscorcia-Gutierrez Margarita Gamarra Romany F.Mansour 《Computers, Materials & Continua》 SCIE EI 2021年第11期2031-2044,共14页
White Blood Cell(WBC)cancer or leukemia is one of the serious cancers that threaten the existence of human beings.In spite of its prevalence and serious consequences,it is mostly diagnosed through manual practices.The... White Blood Cell(WBC)cancer or leukemia is one of the serious cancers that threaten the existence of human beings.In spite of its prevalence and serious consequences,it is mostly diagnosed through manual practices.The risks of inappropriate,sub-standard and wrong or biased diagnosis are high in manual methods.So,there is a need exists for automatic diagnosis and classification method that can replace the manual process.Leukemia is mainly classified into acute and chronic types.The current research work proposed a computer-based application to classify the disease.In the feature extraction stage,we use excellent physical properties to improve the diagnostic system’s accuracy,based on Enhanced Color Co-Occurrence Matrix.The study is aimed at identification and classification of chronic lymphocytic leukemia using microscopic images of WBCs based on Enhanced Virtual Neural Network(EVNN)classification.The proposed method achieved optimum accuracy in detection and classification of leukemia from WBC images.Thus,the study results establish the superiority of the proposed method in automated diagnosis of leukemia.The values achieved by the proposed method in terms of sensitivity,specificity,accuracy,and error rate were 97.8%,89.9%,76.6%,and 2.2%,respectively.Furthermore,the system could predict the disease in prior through images,and the probabilities of disease detection are also highly optimistic. 展开更多
关键词 White blood cells enhanced virtual neural networking SEGMENTATION feature extraction chronic lymphocytic leukemia
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Determinants of Detection of Stones and Calcifications in the Hepatobiliary System on Virtual Nonenhanced Dual-energy CT 被引量:1
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作者 Da-ming Zhang Xuan Wang +4 位作者 Hua-dan Xue Zheng-yu Jin Hao Sun Yu Chen Yong-lan He 《Chinese Medical Sciences Journal》 CAS CSCD 2016年第2期76-82,共7页
Objective To retrospectively determine the features of stones and calcifications in hepatobiliary system on virtual nonenhanced (VNE) dual-energy computed tomography (CT), and to evaluate the possibility of VNE images... Objective To retrospectively determine the features of stones and calcifications in hepatobiliary system on virtual nonenhanced (VNE) dual-energy computed tomography (CT), and to evaluate the possibility of VNE images in diagnosis for those lesions. Methods A total of 128 gall stones and calcifications of the liver found in 110 patients were examined with triple phase abdominal CT scan from July 2007 to December 2011, in which true nonenhanced (TNE) phase and arterial phase were performed with single-energy CT (120 kVp) and portal venous phase was performed with dual-energy CT (100 kVp and 140 kVp). VNE images were generated from the portal venous phase dual-energy CT data sets by using commercially VNC software. The mean CT values for the stone, liver, bile and paraspinal muscle, mean lesion density and size in area dimension, contrast-to-noise ratio (CNR) of lesion to the liver or bile, and image noise were assessed and compared between VNE and TNE images. The effective dose and size-specific dose estimate (SSDE) were also calculated. Results The mean CT values of the lesions measured on VNE images declined significantly compared with those measured on TNE images (164.51±102.13vs. 290.72±197.80 HU,P<0.001), so did the lesion-to-liver CNR (10.80±11.82vs.18.81±17.06,P<0.001) and the lesion-to-bile CNR (17.24±14.41 vs. 21.32±17.31,P<0.001). There was no significant difference in size of lesions area between VNE and TNE images (0.69±0.88vs.0.72±0.85 cm2,P=0.062). Compared to the 128 lesions found in TNE images, VNE images showed the same density in 30 (23.4%) lesions, lighter density in 88 (68.8%) lesions, while failed to show 10 (7.8%) lesions, and showed the same size in 61 (47.7%) lesions and smaller size in 57 (44.5%)&nbsp;lesions. The CT cutoff values of lesion and size were 229.21 HU and 0.15 cm2, respectively. The total effective dose for triple phase scan protocol with TNE images was 19.51±7.03 mSv, and the SSDE was 39.84±11.10 mGy. The effective dose for dual phase scan protocol with VNE images instead of TNE images was 13.29±4.89 mSv, and the SSDE was 27.83±9.99 mGy. Compared with TNE images, the effective dose and SSDE of VNE images were down by 32.05%±3.69 % and 30.63%±2.34 %, respectively. Conclusions Although the CT values and CNR of the lesions decreased in VNE images, the lesions of which attenuation greater than 229.21 HU and size larger than 0.15 cm2could be detected with good reliability and obvious dose reduction. There was good consistency in the size of stones and calcifications in hepatobiliary system between VNE images and TNE images, which ensured the possibility of the clinical application of VNE images. 展开更多
关键词 virtual non-enhanced STONE CALCIFICATION hepatobiliary system dual-energy computed tomography
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VR/AR-AdaptFace:面向虚拟现实与增强现实的自适应多模态面部替换模型
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作者 靳聪 周满玲 +3 位作者 林美秀 张佳一 王晶 刘淼 《中国传媒大学学报(自然科学版)》 2024年第4期55-63,共9页
随着VR/AR技术的迅猛发展,用户对于沉浸式体验的需求日益增长。同时,虚拟人脸技术亦趋成熟。基于此,本文探索将高度拟真的虚拟人脸融入VR/AR,以增强用户体验的自然度与沉浸感。然而,在虚拟数字人领域,图像生成及换脸技术在VR/AR环境下... 随着VR/AR技术的迅猛发展,用户对于沉浸式体验的需求日益增长。同时,虚拟人脸技术亦趋成熟。基于此,本文探索将高度拟真的虚拟人脸融入VR/AR,以增强用户体验的自然度与沉浸感。然而,在虚拟数字人领域,图像生成及换脸技术在VR/AR环境下仍遇诸多挑战,尤其是唇形合成模型在动态场景及多语言环境下的性能需进一步优化。为解决上述问题,本文提出VR/AR-AdaptFace模型,一个面向虚拟现实与增强现实的自适应多模态面部替换方案。该模型由两大模块构成:“文颜绘真”模块,采用先进的文本至图像转换技术和特定类别先验保存策略,优化虚拟人脸生成,并通过注意力机制大幅提升图像质量;“语唇映生”模块,依托强大的生成器、唇形同步判别器及视觉质量判别器,实现语音与唇形的精准同步,为VR/AR场景中的动态交互带来更加逼真的体验。 展开更多
关键词 人脸合成 细节增强模型 动态视频唇形合成 虚拟现实 增强现实
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新质生产力与基本经济模态转换 被引量:30
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作者 王国成 程振锋 《当代经济科学》 CSSCI 北大核心 2024年第3期71-79,共9页
在建设中国式现代化的新时代征程中,习近平总书记创造性地提出具有深邃意蕴的“新质生产力”概念,丰富并提升了生产力理论,是马克思主义中国化和时代化的积极探索。以生产力中的劳动者主体为切入视角和逻辑主线,着重从机理上分析新质生... 在建设中国式现代化的新时代征程中,习近平总书记创造性地提出具有深邃意蕴的“新质生产力”概念,丰富并提升了生产力理论,是马克思主义中国化和时代化的积极探索。以生产力中的劳动者主体为切入视角和逻辑主线,着重从机理上分析新质生产力与生产方式、生产关系、运行机制和结构演变等方面的内在关联,以及对促进高质量发展的核心和全局作用。第一,明确提出科技与人文深度融合的“虚实交融”的新质生产力;第二,分析指出了新质生产力与高质量发展、基本经济模态转换之间的关联机理和内在逻辑;第三,初步刻画了新经济模态的基本特征、主体构成及运行原理等。运用马克思主义政治经济学的基本原理,秉承中国共产党以人民为中心的执政理念和宗旨,强化劳动者的主体地位,提出了加快形成新质生产力促进高质量发展和中国式现代化建设的政策蕴含与启示。 展开更多
关键词 新质生产力 生产方式 生产关系 劳动者 虚实交融 科技创新 经济模态 高质量发展
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Fabrication and Characterization of Strained Si Material Using SiGe Virtual Substrate for High Mobility Devices 被引量:2
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作者 梁仁荣 张侃 +3 位作者 杨宗仁 徐阳 王敬 许军 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第10期1518-1522,共5页
The fabrication and characterization of strained-Si material grown on a relaxed Si0.79 Ge0.21/graded Si1-x- Gex/Si virtual substrate, using reduced pressure chemical vapor deposition, are presented. The Ge concentrati... The fabrication and characterization of strained-Si material grown on a relaxed Si0.79 Ge0.21/graded Si1-x- Gex/Si virtual substrate, using reduced pressure chemical vapor deposition, are presented. The Ge concentration of the constant composition SiGe layer and the grading rate of the graded SiGe layer are estimated with double-crystal X-ray diffraction and further confirmed by SIMS measurements. The surface root mean square roughness of the strained Si cap layer is 2.36nm,and the strain is about 0.83% as determined by atomic force microscopy and Raman spectra, respectively. The threading dislocation density is on the order of 4 × 10^4cm^-2. Furthermore, it is found that the stress in the strained Si cap layer is maintained even after the high thermal budget process, nMOSFET devices are fabricated and measured in strained-Si and unstrained bulk-Si channels. Compared to the co-processed bulk-Si MOSFETs at room temperature,a significant low vertical field mobility enhancement of about 85% is observed in the strained-Si devices. 展开更多
关键词 strained Si RPCVD SiGe virtual substrate mobility enhancement
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基于混合知识蒸馏和特征增强技术的轻量级无解析式虚拟试衣网络
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作者 侯珏 丁焕 +3 位作者 杨阳 陆寅雯 余灵婕 刘正 《纺织学报》 EI CAS CSCD 北大核心 2024年第9期164-174,共11页
基于外观流的二维虚拟试衣技术存在着服装扭曲准确率低、纹理失真以及模型计算成本高等问题,提出了一种基于混合知识蒸馏和特征增强的轻量级无解析式虚拟试衣模型。首先,通过全局特征的融合与不同尺度下流场运算结果的校准,提出了改进... 基于外观流的二维虚拟试衣技术存在着服装扭曲准确率低、纹理失真以及模型计算成本高等问题,提出了一种基于混合知识蒸馏和特征增强的轻量级无解析式虚拟试衣模型。首先,通过全局特征的融合与不同尺度下流场运算结果的校准,提出了改进后的外观流估计方法,提高外观流的估计精度;其次,采用知识蒸馏的方法对图像分割结果与虚拟试衣流程进行解耦,构建了基于深度可分离卷积的轻量级试衣网络;最后,提出了基于像素平均梯度的服装复杂度GTC指标量化分析服装的纹理复杂程度,以此为基础将VITON数据集划分为简易纹理集、较复杂纹理集和复杂纹理集。结果表明:提出的模型在图像质量评价指标(弗雷歇距离、感知图像块相似度、峰值信噪比、内核初始距离)上的分值较目前性能最优的模型均有所提升,能够有效提高服装扭曲准确度与试穿结果图像的质量,缓解服装纹理畸变与失真的问题,同时还拥有更小的模型尺寸和更快的运行推理速度。 展开更多
关键词 虚拟试衣 外观流 知识蒸馏 特征增强技术 服装复杂度 服装电子商务
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三维虚拟图像中动态特征增强算法设计
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作者 薛峰 陶海峰 《吉林大学学报(信息科学版)》 CAS 2024年第5期840-846,共7页
为有效解决三维虚拟图像存在的亮度不均匀的问题,提出一种三维虚拟图像中动态特征增强算法。将中值滤波算法和小波软阈值算法有效结合,对三维虚拟图像进行去噪处理。通过视觉选择特性设定新的结构元,构建连通粒属性以及分层统计模型对... 为有效解决三维虚拟图像存在的亮度不均匀的问题,提出一种三维虚拟图像中动态特征增强算法。将中值滤波算法和小波软阈值算法有效结合,对三维虚拟图像进行去噪处理。通过视觉选择特性设定新的结构元,构建连通粒属性以及分层统计模型对图像进行颜色转换和结构元匹配,得到对应的映射子图,提取动态特征。将三维虚拟图像输入至改进的U-net++网络内,采用不同层密集连接增强不同层次图像特征的关联性,并将全部动态特征融合进行细节重建,实现三维虚拟图像动态特征增强。实验结果表明,所提算法可获取满意的三维虚拟图像中动态特征增强效果。 展开更多
关键词 三维虚拟图像 动态特征 增强 颜色转换 密集连接
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双源CT双能量TNC技术图像质量与诊断肝细胞癌效能分析
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作者 杨佳欣 杨紫郡 陈卫 《实用肝脏病杂志》 CAS 2024年第6期915-918,共4页
目的分析双源CT双能量真实平扫(TNC)技术图像质量和诊断肝细胞癌(HCC)的效能。方法2020年1月~2023年1月我院收治的85例肝占位性病变患者,均接受双源CT双能量增强扫描,获取TNC和虚拟平扫(VNC)图像,计算图像信噪比(SNR)和对比噪声比(CNR)... 目的分析双源CT双能量真实平扫(TNC)技术图像质量和诊断肝细胞癌(HCC)的效能。方法2020年1月~2023年1月我院收治的85例肝占位性病变患者,均接受双源CT双能量增强扫描,获取TNC和虚拟平扫(VNC)图像,计算图像信噪比(SNR)和对比噪声比(CNR)。采用5分法评估图像质量。结果在85例肝占位性病变患者中,经病理学检查诊断HCC 48例,肝局灶性结节增生(FNH)23例和肝血管瘤(HH)14例;HCC病灶TNC图像肝脏病灶和同层面右侧竖脊肌CT值标准差(SD)和辐射剂量分别为(7.9±1.8)HU和(5.9±0.6)mSv,显著大于VNC图像【分别为(6.7±1.3)HU和(3.6±0.7)mSv,P<0.05】,而SNR为(5.4±1.6),显著低于VNC图像【(6.5±1.7),P<0.05】;HCC、FNH和HH病灶TNC图像的SD和辐射剂量均显著大于VNC图像(P<0.05),而SNR显著低于VNC图像(P<0.05);HCC病灶TNC和VNC图像CT值显著大于FNH或HH病灶(P<0.05);HCC病灶TNC图像质量主观评分显著高于VNC图像(P<0.05);TNC图像诊断HCC的敏感度为89.6%、特异度为91.9%、准确率为90.6%,显著优于VNC诊断(分别为72.9%、78.4%和75.3%,P<0.05)。结论虽然双源CT双能量增强扫描辐射剂量稍大,但TNC图像质量好,诊断HCC的准确率高,临床应用价值大。 展开更多
关键词 肝细胞癌 双源CT双能量扫描 真实平扫 虚拟平扫 图像质量 诊断
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加速康复外科理念在基于三维可视化虚拟手术系统的经皮椎间孔镜治疗患者中的应用价值
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作者 马晨溪 范雨露 巩陈 《实用临床医药杂志》 CAS 2024年第11期119-124,共6页
目的探讨加速康复外科理念(ERAS)在基于三维可视化虚拟手术系统的经皮椎间孔镜治疗患者围术期护理中的应用价值。方法采用随机数字表法将86例腰椎管狭窄症患者分为试验组(采用基于ERAS的围术期护理)和对照组(采用常规围术期护理),每组4... 目的探讨加速康复外科理念(ERAS)在基于三维可视化虚拟手术系统的经皮椎间孔镜治疗患者围术期护理中的应用价值。方法采用随机数字表法将86例腰椎管狭窄症患者分为试验组(采用基于ERAS的围术期护理)和对照组(采用常规围术期护理),每组43例。比较2组患者术后恢复情况、疼痛程度[视觉模拟评分法(VAS)评分]、腰椎功能[日本骨科协会(JOA)腰痛疾患评定表评分]、康复积极性[匹兹堡康复参与量表(PRPS)评分]、配合度[治疗依从性评分量表(ARS)评分]、生活质量[世界卫生组织生存质量测定简表(WHOQOL-BREF)评分]、并发症情况和满意度。结果试验组术后首次下床时间、术后首次进食时间、住院时间均短于对照组,差异有统计学意义(P<0.05);试验组并发症总发生率为9.30%,低于对照组的27.91%,差异有统计学意义(P<0.05);术后3 d,试验组VAS评分为(1.77±0.58)分,低于对照组的(2.54±0.72)分,差异有统计学意义(P<0.05);干预后,试验组JOA腰痛疾患评定表评分、PRPS评分、WHOQOL-BREF评分、满意度评分均高于对照组,ARS评分低于对照组,差异有统计学意义(P<0.05)。结论将ERAS应用于基于三维可视化虚拟手术系统的经皮椎间孔镜治疗患者的围术期护理中,不仅能够缩短腰椎管狭窄症患者术后首次下床时间、术后首次进食时间和住院时间,提高康复积极性和配合度,显著减轻疼痛,还能促进腰椎功能恢复,减少并发症的发生,有效提升生活质量和患者满意度。 展开更多
关键词 腰椎管狭窄症 三维可视化虚拟手术系统 经皮椎间孔镜 围术期护理 加速康复外科理念
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Precision in detecting colon lesions:A key to effective screening policy but will it improve overall outcomes?
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作者 Luis Ramon Rabago Maria Delgado Galan 《World Journal of Gastrointestinal Endoscopy》 2024年第3期102-107,共6页
Colonoscopy is the gold standard for the screening and diagnosis of colorectal cancer,resulting in a decrease in the incidence and mortality of colon cancer.However,it has a 21%rate of missed polyps.Several strategies... Colonoscopy is the gold standard for the screening and diagnosis of colorectal cancer,resulting in a decrease in the incidence and mortality of colon cancer.However,it has a 21%rate of missed polyps.Several strategies have been devised to increase polyp detection rates and improve their characterization and delimi-tation.These include chromoendoscopy(CE),the use of other devices such as Endo cuffs,and major advances in endoscopic equipment[high definition,magnification,narrow band imaging,i-scan,flexible spectral imaging color enhancement,texture and color enhancement imaging(TXI),etc.].In the retrospective study by Hiramatsu et al,they compared white-light imaging with CE,TXI,and CE+TXI to determine which of these strategies allows for better definition and delimitation of polyps.They concluded that employing CE associated with TXI stands out as the most effective method to utilize.It remains to be demonstrated whether these results are extrapolatable to other types of virtual CE.Additionally,further investigation is needed in order to ascertain whether this strategy could lead to a reduction in the recurrence of excised lesions and potentially lower the occurrence of interval cancer. 展开更多
关键词 Colonoscopy screening Interval colorectal cancer Post colonoscopy colorectal cancer CHROMOENDOSCOPY virtual chromoendoscopy high-definition whitelight endoscopy Texture and color enhancement imaging Indigo carmine ADENOMA Sessile serrated lesion
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基于虚拟传感器的结构位移视觉测量误差抑制方法
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作者 周华飞 梁一鸣 《浙江工业大学学报》 CAS 北大核心 2024年第3期305-311,共7页
温度、热浪和振动等环境因素给结构位移监测造成不可忽视的误差。虽然利用静止标志物降低视觉测量误差的原理可行,但是其适用范围却因背景标志物不易获得和控制而受到很大限制。利用视觉测量系统的现有条件,在近场布置主动光源作为误差... 温度、热浪和振动等环境因素给结构位移监测造成不可忽视的误差。虽然利用静止标志物降低视觉测量误差的原理可行,但是其适用范围却因背景标志物不易获得和控制而受到很大限制。利用视觉测量系统的现有条件,在近场布置主动光源作为误差检测虚拟传感器,摆脱对天然标志物的依赖。针对焦外成像产生的弥散圆等伴生问题,采用图像滤波、伽马变换、图像质量评估、图像二值化、边缘检测和目标检测等算法,形成一套面向弥散圆光斑的自适应图像增强算法;利用虚拟传感器的虚假位移,实现结构位移测量误差补偿,开展了仿真实验和室外结构位移视觉测量实验。研究结果表明:该方法可以显著降低结构位移的初始误差,残留误差满足测量精度要求。 展开更多
关键词 视觉测量 虚拟传感器 误差抑制 弥散圆光斑 图像增强 自适应
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基于姿势引导下的虚拟试穿网络
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作者 黄东晋 李晓敏 +1 位作者 刘金华 李贞妍 《上海大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期491-502,共12页
针对现有的基于姿势引导下的虚拟试穿方法存在着服装纹理过度变形、生成的图像出现遮挡等问题,提出了一种基于姿势引导下的虚拟试穿网络(pose-guidedvirtualtry-on network,PG-VTON).首先,使用基于U-Net的网络对人物图像进行姿势转换,... 针对现有的基于姿势引导下的虚拟试穿方法存在着服装纹理过度变形、生成的图像出现遮挡等问题,提出了一种基于姿势引导下的虚拟试穿网络(pose-guidedvirtualtry-on network,PG-VTON).首先,使用基于U-Net的网络对人物图像进行姿势转换,生成目标姿势下的人物解析图,引入信息增强模块提高解析图的准确性,减少试穿中的错误遮挡;然后,通过薄板样条变换(thin platespline,TPS)方法将目标服装变形为与人物身体相贴合的形状,引入网格变形约束项来保留目标服装的纹理和细节特征;最后,将解析图和变形服装结合起来,生成最终的虚拟试穿图像.实验结果表明,该方法不仅比Downto(downtothelast detail)网络试穿图像的平均结构相似性(structural similarity,SSIM)提高了2.83%,初始得分(inception score,IS)提高了6.74%,与其他最新的虚拟试穿方法相比减少了试穿过程中的错误遮挡,能生成更加清晰真实的结果. 展开更多
关键词 虚拟试穿 薄板样条变换 信息增强模块 网格变形约束项
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图像增强内窥镜在结直肠病变检测中的应用进展
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作者 丁亚利 陈日寿 曾今诚 《实用医学杂志》 CAS 北大核心 2024年第21期3006-3012,共7页
图像增强内窥镜(IEE)是一种内窥镜成像技术,可用于改善胃肠道病变的黏膜表面形态和微血管系统特征的可视化,在实时诊断中起着至关重要的作用。使用不同的工具和技术可以进行实时光学诊断,例如窄带成像(NBI)、宾得内窥镜(i-SCAN)、柔性... 图像增强内窥镜(IEE)是一种内窥镜成像技术,可用于改善胃肠道病变的黏膜表面形态和微血管系统特征的可视化,在实时诊断中起着至关重要的作用。使用不同的工具和技术可以进行实时光学诊断,例如窄带成像(NBI)、宾得内窥镜(i-SCAN)、柔性光谱成像色彩增强(FICE)、蓝色激光成像(BLI)和联动彩色成像(LCI)等。该文就IEE在结直肠病变检测中的应用进展进行综述,以期为临床检测结直肠病变提供新的理论依据。 展开更多
关键词 图像增强内窥镜 结直肠病变 基于染料的色素内窥镜 基于设备的虚拟色素内窥镜
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商业虚拟现实游戏在心理学中的应用与展望
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作者 王润东 麻珂 《应用心理学》 CSSCI 2024年第2期118-127,共10页
虚拟现实游戏结合了虚拟现实技术和电子游戏的特征,可以作为干预和训练手段,用于改善人们的心理状态和认知能力表现。虚拟现实游戏可分为严肃游戏和商业游戏。严肃游戏对人们心理和行为的影响,已有较多研究。而使用商业游戏进行的心理... 虚拟现实游戏结合了虚拟现实技术和电子游戏的特征,可以作为干预和训练手段,用于改善人们的心理状态和认知能力表现。虚拟现实游戏可分为严肃游戏和商业游戏。严肃游戏对人们心理和行为的影响,已有较多研究。而使用商业游戏进行的心理学研究目前还并不多。本文回顾了商业虚拟现实游戏在运动健康、认知训练,及心理干预等领域中的研究发现。然而,影响商业虚拟现实游戏在心理学中应用的因素以及干预效果,还有待进一步的研究。 展开更多
关键词 运动健康 认知训练 心理干预 商业虚拟现实游戏
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虚拟现实技术下激光三维无障碍空间图像增强算法
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作者 樊丹丹 《激光杂志》 CAS 北大核心 2024年第10期125-129,共5页
与普通空间图像相比,激光三维无障碍空间图像包含信息量更多,给图像的增强算法带来较大难度,为了提高激光三维无障碍空间图像质量,提出虚拟现实技术下激光三维无障碍空间图像增强算法。在虚拟现实技术下,生成激光三维无障碍空间图像,采... 与普通空间图像相比,激光三维无障碍空间图像包含信息量更多,给图像的增强算法带来较大难度,为了提高激光三维无障碍空间图像质量,提出虚拟现实技术下激光三维无障碍空间图像增强算法。在虚拟现实技术下,生成激光三维无障碍空间图像,采用双边和引导滤波相结合的方式进行去噪处理,提取图像特征,通过去模糊、变换增强、细节特征增强、颜色增强等步骤,得出激光三维无障碍空间图像的增强处理结果。通过测试实验得出结论:与传统图像增强算法相比,优化设计算法得出增强图像的信噪比和对比度更高,分别提升约49 dB和68 dB,由此证明优化设计算法具有更优的图像增强效果。 展开更多
关键词 虚拟现实技术 激光图像 三维无障碍空间图像 图像增强
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一种基于混合微调策略的虚拟机异常检测器增强方法
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作者 丁锐 《科技资讯》 2024年第16期48-51,共4页
虚拟机异常检测器在现实场景中面临训练数据样本稀疏的问题,为了实现稀疏样本条件下的虚拟机异常精准检测,提出了一种基于混合微调策略的虚拟机检测增强方法。首先,利用大语言模型,基于提示工程,对收集的虚拟机逃逸样本进行提升工程,得... 虚拟机异常检测器在现实场景中面临训练数据样本稀疏的问题,为了实现稀疏样本条件下的虚拟机异常精准检测,提出了一种基于混合微调策略的虚拟机检测增强方法。首先,利用大语言模型,基于提示工程,对收集的虚拟机逃逸样本进行提升工程,得到增强的样本。其次,采用LoRA和PreFix混合微调策略对收集的虚拟机逃逸样本进行提升工程,得到增强的样本。再次,利用增强样本对预训练大模型ChatGLM进行微调,生成一种专用于生成虚拟机逃逸数据的模型。最后,利用专用模型生成的样本扩充数据集,增强基于学习的虚拟机异常检测器。通过实验验证,此方法显著提升了虚拟机逃逸检测的准确性,并降低了误报率。 展开更多
关键词 异常检测 虚拟机 微调策略 样本增强
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Findings on intraprocedural non-contrast computed tomographic imaging following hepatic artery embolization are associated with development of contrast-induced nephropathy 被引量:1
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作者 Mohamed M Soliman Debkumar Sarkar +1 位作者 Ilya Glezerman Majid Maybody 《World Journal of Nephrology》 2020年第2期33-42,共10页
BACKGROUND Contrast-induced nephropathy(CIN)is a reversible form of acute kidney injury that occurs within 48-72 h of exposure to intravascular contrast material.CIN is the third leading cause of hospital-acquired acu... BACKGROUND Contrast-induced nephropathy(CIN)is a reversible form of acute kidney injury that occurs within 48-72 h of exposure to intravascular contrast material.CIN is the third leading cause of hospital-acquired acute kidney injury and accounts for 12%of such cases.Risk factors for CIN development can be divided into patientand procedure-related.The former includes pre-existing chronic renal insufficiency and diabetes mellitus.The latter includes high contrast volume and repeated exposure over 72 h.The incidence of CIN is relatively low(up to 5%)in patients with intact renal function.However,in patients with known chronic renal insufficiency,the incidence can reach up to 27%.AIM To examine the association between renal enhancement pattern on non-contrast enhanced computed tomographic(CT)images obtained immediately following hepatic artery embolization with development of CIN.METHODS Retrospective review of all patients who underwent hepatic artery embolization between 01/2010 and 01/2011(n=162)was performed.Patients without intraprocedural CT imaging(n=51),combined embolization/ablation(n=6)and those with chronic kidney disease(n=21)were excluded.The study group comprised of 84 patients with 106 procedures.CIN was defined as 25%increase above baseline serum creatinine or absolute increase≥0.5 mg/dL within 72 h post-embolization.Post-embolization CT was reviewed for renal enhancement patterns and presence of renal artery calcifications.The association between noncontrast CT findings and CIN development was examined by Fisher’s Exact Test.RESULTS CIN occurred in 11/106(10.3%)procedures(Group A,n=10).The renal enhancement pattern in patients who did not experience CIN(Group B,n=74 with 95/106 procedures)was late excretory in 93/95(98%)and early excretory(EE)in 2/95(2%).However,in Group A,there was a significantly higher rate of EE pattern(6/11,55%)compared to late excretory pattern(5/11)(P<0.001).A significantly higher percentage of patients that developed CIN had renal artery calcifications(6/11 vs 20/95,55%vs 21%,P=0.02).CONCLUSION A hyperdense renal parenchyma relative to surrounding skeletal muscle(EE pattern)and presence of renal artery calcifications on immediate post-HAE noncontrast CT images in patients with low risk for CIN are independently associated with CIN development. 展开更多
关键词 Hepatic artery embolization non-contrast computed tomographic Contrastinduced nephropathy Renal enhancement pattern INTRA-ARTERIAL Renal artery calcification
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A Virtual Walk along Street Based on View Interpolation
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作者 Shuang-Mei Wang 《Journal of Electronic Science and Technology》 CAS 2013年第4期408-411,共4页
Image morphing is a powerful tool for visual effect. In this paper, a view interpolation algorithm is proposed to simulate a virtual walk along a street from start position to end position. To simulate a virtual walki... Image morphing is a powerful tool for visual effect. In this paper, a view interpolation algorithm is proposed to simulate a virtual walk along a street from start position to end position. To simulate a virtual walking view needs to create new appearing scene in the vision-vanishing point and disappearing scene beyond the scope of view. To attain these two aims we use two enhanced position parameters to match pixels of source images and target images. One enhanced position parameter is the angular coordinates of pixels. Another enhanced position parameter is the distances from pixels to the vision-vanishing point. According to the parameter values, pixels beyond the scope of view can be "moved" out in linear interpolation. Result demonstrates the validity of the algorithm. Another advantage of this algorithm is that the enhanced position parameters are based on real locations and walking distances, so it is also an approach to online virtual tour by satellite maps of virtual globe applications such as Google Earth. 展开更多
关键词 enhanced position parameter featureregion linear interpolation scope of view virtual walk.
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Virtual chromoendoscopy in small bowel capsule endoscopy: New light or a cast of shadow?
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作者 José Cotter Joana Magalh es +5 位作者 Francisca Dias de Castro Mara Barbosa Pedro Boal Carvalho Sílvia Leite Maria Jo o Moreira Bruno Rosa 《World Journal of Gastrointestinal Endoscopy》 2014年第8期359-365,共7页
AIM: To evaluate whether virtual chromoendoscopy can improve the delineation of small bowel lesions previously detected by conventional white light small bowel capsule endoscopy(SBCE). METHODS: Retrospective single ce... AIM: To evaluate whether virtual chromoendoscopy can improve the delineation of small bowel lesions previously detected by conventional white light small bowel capsule endoscopy(SBCE). METHODS: Retrospective single center study. One hundred lesions selected from forty-nine consecutive conventional white light SBCE(SBCE-WL) examinations were included. Lesions were reviewed at three Flexible Spectral Imaging Color Enhancement(FICE) settings and Blue Filter(BF) by two gastroenterologists with ex-perience in SBCE, blinded to each other's findings, whoranked the quality of delineation as better, equivalent or worse than conventional SBCE-WL. Inter-observer percentage of agreement was determined and analyzed with Fleiss Kappa(k) coefficient. Lesions selected for the study included angioectasias(n = 39), ulcers/ero-sions(n = 49) and villous edema/atrophy(n = 12). RESULTS: Overall, the delineation of lesions was im-proved in 77% of cases with FICE 1, 74% with FICE 2, 41% with FICE 3 and 39% with the BF, with a percent-age of agreement between investigators of 89%(k = 0.833), 85%(k = 0.764), 66%(k = 0.486) and 79%(k = 0.593), respectively. FICE 1 improved the delineation of 97.4% of angioectasias, 63.3% of ulcers/erosions and 66.7% of villous edema/atrophy with a percentage of agreement of 97.4%(k = 0.910), 81.6%(k = 0.714) and 91.7%(k = 0.815), respectively. FICE 2 improved the delineation of 97.4% of angioectasias, 57.1% of ulcers/erosions and 66.7% of villous edema/atrophy, with a percentage of agreement of 89.7%(k = 0.802), 79,6%(k = 0.703) and 91.7%(k = 0.815), respectively. FICE 3 improved the delineation of 46.2% of angioecta-sias, 24.5% of ulcers/erosions and none of the cases of villous edema/atrophy, with a percentage of agreement of 53.8% [k = not available(NA)], 75.5%(k = NA) and 66.7%(k = 0.304), respectively. The BF improved the delineation of 15.4% of angioectasias, 61.2% of ulcers/erosions and 25% of villous edema/atrophy, with a per-centage of agreement of 76.9%(k = 0.558), 81.6%(k = 0.570) and 25.0%(k = NA), respectively.CONCLUSION: Virtual chromoendoscopy can improve the delineation of angioectasias, ulcers/erosions and villous edema/atrophy detected by SBCE, with almost perfect interobserver agreement for FICE 1. 展开更多
关键词 Capsule endoscopy virtual chromoendoscopy Small bowel enteroscopy Flexible Spectral Imaging Color enhancement Endoscopy Imaging review
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