MRI 3D CUBE T_(2)序列检查在踝关节外伤患者韧带损伤诊断中的价值

目的:研究MRI 3D CUBE T_(2)序列检查在踝关节外伤患者韧带损伤诊断中的价值。方法:选择2020年4月—2023年4月于白银市第一人民医院就诊的226例踝关节外伤拟行手术术前患者作为研究对象,按照不同检查方式将患者分为观察组(n=126)与对照组(n=100)。观察组采用MRI 3D CUBE T_(2)序列检查,对照组采取常规MRI检查。比较两组患侧、健侧距腓前韧带测量结果、诊断效能。结果:两组患侧、健侧距腓前韧带宽度及厚度比较,差异无统计学意义(P>0.05)。观察组Ⅰ级踝关节外伤患者韧带损伤诊断准确度、敏感度、特异度、阳性预测值、阴性预测值高于对照组,Ⅱ级患者准确度、敏感度、阴性预测值高于对照组,Ⅲ级患者准确度、特异度、阳性预测值高于对照组,差异有统计学意义(P<0.05)。结论:MRI 3D CUBE T_(2)序列检查踝关节外伤患者韧带损伤诊断效能高于常规MRI检查,可作为治疗效果评价及康复治疗的重要依据。

CUBE T2FLAIR与3D BRAVO序列在脑转移瘤中的应用

目的:探讨CUBE T2FLAIR及3D BRAVO序列在脑转移瘤中的临床应用价值。方法:对2019年1月-2020年9月佛山市第二人民医院23例脑转移瘤患者行常规扫描后再行3D BRAVO和CUBE T2FLAIR序列增强扫描,根据部位比较2种序列显示转移瘤的数目。结果:23例共452个病灶,CUBE T2FLAIR显示488个病灶,显示率82.6%,3D BRAVO显示378个病灶,显示率65.2%,两者比较差异无统计学意义(P=0.157)。结论:CUBE T2FLAIR和3D BRAVO对脑转移瘤诊断价值相当,CUBE T2FLAIR增强显示转移瘤更为明显,能做3D BRAVO序列的补充。

MR 3D CUBE技术对膝关节前交叉韧带损伤的诊断价值

目的探讨MR 3D CUBE技术对膝关节前交叉韧带损伤的诊断价值。材料与方法对膝关节损伤拟行手术病人术前行MR扫描,以关节镜所见为参考依据,对80例患者86个膝关节行常规MRI序列扫描后加扫3D CUBE T2WI序列,运用AW4.4工作站对3D图像进行后处理重建。分别与关节镜术后结果进行对比分析,计算常规MRI序列及3D CUBE技术在诊断前交叉韧带损伤中的特异度、灵敏度及准确度。结果 3D CUBE T2WI序列在诊断前交叉韧带损伤特异度89%、灵敏度95%、准确度84%;常规MRI序列在诊断前交叉韧带损伤的特异度68%、灵敏度83%、准确度51%。结论 3DCUBE序列扫描时间短,图像可多角度任意旋转,可显示完整前交叉韧带,对前交叉韧带损伤的特异度、灵敏度及准确度较常规MRI序列高。

Some improvements of the marching cubes algorithm for the rendering of an orebody

Orebody-rendering techniques are developed using the marching cubes (MC) algorithm. The shape of an orebody is viv- idly displayed in real time and can be used to guide mining design as well. The MC algorithm has been improved in two aspects. By analyzing the principles of the MC algorithm, as well as the features of the specific application, improvements were developed to: eliminate ambiguities by using a unified isosurface constructing method in the voxels, and improve the operating efficiency of the MC algorithm by incorporating an octree structure. The analytical results of the examples demonstrate the effectiveness of our proposal.

3D Bravo、3D Cube Flair两种MR增强扫描序列用于肺癌脑转移病灶的检验能力比较

目的探讨3D Bravo、3D Cube Flair两种MR增强扫描序列用于肺癌脑转移病灶的检验能力。方法选择我院肿瘤科2016年1月至2020年1月期间收治100例肺癌脑转移病灶患者为研究对象,全部观察对象均分别接受本研究方案的MR增强扫描,对比两组检查技术的检出情况、判读结果和信号强度。结果3D Bravo MR增强扫描对于脑膜转移和脑内转移的临床检出率均明显高于3D Cube Flair MR增强扫描,两种方法病灶部位检出数据对比差异具有统计学意义(P<0.05),3D Bravo序列检出率为93.2%,漏诊率6.8%,误诊率为0.4%,3D Cube Flair序列检出率96.8%,漏诊率3.2%,误诊率为1.4%,数据分析结果比较差异具有统计学意义(P<0.05),两种序列的图像质量都比较理想,但部分患者可见伪影情况,3D Bravo和3D Cube Flair序列图像测量的信号强度CR符合正态性分布特征,但两者病灶与正常灰质、病灶与正常白质的信号强度对比差异具有统计学意义(P<0.05)。结论3D Cube Flair序列MR增强扫描用于肺癌脑转移病灶的检查和诊断,应用效果较好,但3D Bravo与3D Cube Flair序列联合应用能够提高检查的可靠性。

A marching cube algorithm based on edge growth

The marching cube algorithm is currently one of the most popular three-dimensional(3D)reconstruction surface rendering algorithms.It forms cube voxels based on an input image and then uses 15 basic topological configurations to extract isosurfaces from the voxels.The algorithm processes each cube voxel in a traversal-based manner,but it does not consider the relationship between the isosurfaces in adjacent cubes.Owing to ambiguity,the final reconstructed model may have holes.In this paper,we propose a marching cube algorithm based on edge growth.The algorithm first extracts seed triangles,grows these seed triangles,and then reconstructs the entire 3D model.According to the position of the growth edge,we propose 17 topological configurations with isosurfaces.The reconstruction results showed that the algorithm can reconstruct the 3D model well.When only the main contour of the 3D model is required,the algorithm performs well.In addition,when there are multiple scattered parts in the data,the algorithm can extract only the 3D contours of the parts connected to the seed by setting the region selected based on the seed.

Vertebrae CT Images 3D Reconstruction with Improve Marching Cubes Algorithm

Medical images 3D reconstruction is an important part in medical image analysis and processing. Although lots of algorithms have been proposed continuously, speed and accuracy cannot conform to actual needs, which has always been the focus topic. In this paper, we propose an Improved Marching Cubes algorithm ( I-MC) based on the surface rendering theory, which implements 3D reconstruction of the vertebrae. Firstly, we preprocessed the original 2D vertebrae CT images with the bilateral-filter denoising algorithm. Secondly, on the basis of the traditional Marching Cubes algorithm, the seed voxels were extracted and the Region Growing algorithm was used to determine all voxels that contain isosurfaces. Then, the Golden Section instead of the traditional linear interpolation was used to calculate the equivalent point, and this method reduced the calculations of public edges. VTK and OpenGL implemented 3D reconstruction of the vertebrae on GPU quickly and accurately. The experimental results show that when compared with the traditional Marching Cubes algorithm and Mesh Simplification Marching Cubes algorithm, the improved algorithm achieves a significant improvement of reconstruction speed while preserving the accurate results. The efficiency of algorithm is improved dramatically. This method is real-time and achieves the goal of efficient 3D reconstruction of vertebrae CT images.

Transition Dipole, Charge Transfer, and Electron-hole Coherence in Two-photon Absorption： Visualizations with Two Dimensional Site and Three Dimensional Cube Representations

The developed visualization methods of two dimensional （2D） site and three dimensional （3D） cube representations have been performed to show the orientation of transition dipole, charge transfer, and electron-hole coherence in two-photon absorption （TPA）. The 3D cube representations of transition density can reveal visually the orientation and strength of transition dipole moment, and charge different density show the orientation of charge transfer in TPA. The 2D site representation can reveal visually the electron-hole coherence in TPA. The combination of 2D site and 3D cube representations provide clearly inspect into the charge transfer process and the contribution of excited molecular segments for TPA.

未来照进现实 Celluon magic Cube虚拟投影键盘

原本按照MI的想法，这样一款超酷的产品，肯定又是某个配件厂商专为苹果iPad设计的，因为炫酷的iPad键盘配件已经不是第一次出现了。不过在深入了解了Magic Cube后，你就会发现，它从来没有这样想过。

MAGIC CUBE——索尼Cyber-shot T2数码相机

数码相机对于像素的追求似乎永无止境，在消费者强烈需求和厂商技术突破的多重推动下，从几十万像素到千万像素的跨越，并没有花费太多的时间。但在像素接近和到达千万级别的时候，普通民用数码相机（特别是卡片机）对于像素的需求就显得不那么强烈了。毕竟对于大多数用户而言，能够满足5～7英寸照片冲印的500万～800万像素已经绰绰有余。在到达这个数码相机发展的瓶颈时，厂商们也开始在其他方面做文章，以刺激新的市场需求，市场细分也就成为必然结果。在时尚数码相机领域有着极佳口碑的索尼，更是在2007年年末之前推出了全新的T系列产品——以满足年轻一族时尚诉求为目标，以五色绚彩为表现形式的幻彩魔方Cyber—shotT2（以下简称T2）。

卷土重来——D Cube出新品D5

复出的韩国品牌D Cube继首发之作D4后,又推出了第二款产品D5。D5仍是一款具备视频播放功能的MP3播放器产品,它的主要特点是加载了WiseAudio技术。WiseAudio是韩国Klisten公司推出一项软件技术,用于为听音者量身定做合适的听音环境。

基于生态位适宜度的耕地“三位一体”空间保护分区研究——以江西省兴国县为例

以兴国县村域为单元,从耕地数量、质量和生态三个维度构建指标体系,运用生态位适宜度模型、改进CRITIC法和综合指数法开展耕地“三位一体”综合评价,并分析其空间分异特征。同时,运用三维魔方法划分耕地保护分区,并提出不同的保护利用措施,以期为耕地保护动态监管政策制定和国土空间规划的编制提供技术支撑。

磁共振Bravo序列与Cube Flair序列对肺癌脑转移患者的应用比较

目的比较分析3D Bravo及3D Cube Flair两种MR增强扫描序列对肺癌脑转移检出能力的优劣,优化肺癌脑转移病例的MR检查方案。方法回顾分析25例临床确诊的肺癌患者的MR检查结果,患者MR检查时同时行3D Bravo及3D Cube Flair两种MR增强扫描序列,比较两者的病灶显示能力并作统计分析。结果 3D Cube flair共检出135个病灶,其中脑膜转移灶78个、脑内转移灶57个;3D Bravo共检出91个病灶,其中脑膜转移灶36、脑内转移灶55个。脑膜转移者两种扫描序列相比P<0.01,有明显差异;脑内转移者两种扫描序列相比P>0.05,无差异。结论 3D Cube Flair增强扫描序列在早期判断肺癌脑转移尤其是早期脑膜转移具有较高应用价值,与3D Bravo扫描序列联合应用对诊断价值更高。

风电场地形绕流的CFD结果确认研究

掌握复杂地形区域的风能分布对风电场微观选址至关重要。为把CFD技术应用于风场中实际地形的风流动模拟,本文选择三种具有实验数据的典型地形进行数值计算,并对数值结果进行确认研究。文中简述了不同网格和不同湍流模型对旋涡位置和速度分布的影响,并探讨了为增加风能利用率,如何确定风力机的最佳安装位置。

Geomagic软件在内燃机进气道开发中的应用

基于逆向工程的再设计是现代设计的一种有效而快速的方法,利用ATOS光学扫描设备对某型号内燃机的进气道砂芯进行扫描,使用Geomagic软件和UG软件处理点云数据,并建立进气道的3D模型。一方面,对3D模型进行计算机辅助工程分析(CAE)得到仿真分析的结果;另一方面,通过CAM加工得到了吹风盒模具。通过逆向工程建立的3D模型能够较好地模拟真实部件,对缩短内燃机的研发周期,降低产品成本具有重大意义。

“幻方”与互文——成都天府中心国际社区当代艺术中心创作实践

互文本是古汉语修辞手法,其优点是既能够结构性、整体化地把握主旨,又能将其呈现为画面感强、感染力足的文本。互文思维可总结为“大处考虑,小处对应”,它是设计创作中“趁手”的好方法。在成都天府中心国际社区当代艺术中心“幻方”两个阶段的创作中,建筑师秉持互文思维,在公园城市的宏观背景下,找到了设施融入在地环境且不失自身存在感的得体位置;在元宇宙虚拟的时空场景中,探索了借助人机交互、交叉迭代的方法来运用和拓展互文设计思维的可能性。