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Predicting 3D Radiotherapy Dose-Volume Based on Deep Learning
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作者 Do Nang Toan Lam Thanh Hien +2 位作者 Ha Manh Toan Nguyen Trong Vinh pham trung hieu 《Intelligent Automation & Soft Computing》 2024年第2期319-335,共17页
Cancer is one of the most dangerous diseaseswith highmortality.One of the principal treatments is radiotherapy by using radiation beams to destroy cancer cells and this workflow requires a lot of experience and skill ... Cancer is one of the most dangerous diseaseswith highmortality.One of the principal treatments is radiotherapy by using radiation beams to destroy cancer cells and this workflow requires a lot of experience and skill from doctors and technicians.In our study,we focused on the 3D dose prediction problem in radiotherapy by applying the deeplearning approach to computed tomography(CT)images of cancer patients.Medical image data has more complex characteristics than normal image data,and this research aims to explore the effectiveness of data preprocessing and augmentation in the context of the 3D dose prediction problem.We proposed four strategies to clarify our hypothesis in different aspects of applying data preprocessing and augmentation.In strategies,we trained our custom convolutional neural network model which has a structure inspired by the U-net,and residual blocks were also applied to the architecture.The output of the network is added with a rectified linear unit(Re-Lu)function for each pixel to ensure there are no negative values,which are absurd with radiation doses.Our experiments were conducted on the dataset of the Open Knowledge-Based Planning Challenge which was collected from head and neck cancer patients treatedwith radiation therapy.The results of four strategies showthat our hypothesis is rational by evaluating metrics in terms of the Dose-score and the Dose-volume histogram score(DVH-score).In the best training cases,the Dose-score is 3.08 and the DVH-score is 1.78.In addition,we also conducted a comparison with the results of another study in the same context of using the loss function. 展开更多
关键词 CT image 3D dose prediction data preprocessing augmentation
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豫西地区秦岭造山带武当群火山岩和沉积岩锆石U-Pb年龄 被引量:29
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作者 祝禧艳 陈福坤 +3 位作者 王伟 pham trung hieu 王芳 张福勤 《地球学报》 EI CAS CSCD 北大核心 2008年第6期817-829,共13页
在南秦岭地体中广泛分布着武当群变质沉积—火山岩组合的基底岩石,是东秦岭造山带重要的岩石单元,但对其形成时代的认识存在分歧。笔者通过对豫西地区武当地体北部武当群上部杨坪组变质沉积岩和下部双台组变质中酸性火山岩锆石U-Pb年龄... 在南秦岭地体中广泛分布着武当群变质沉积—火山岩组合的基底岩石,是东秦岭造山带重要的岩石单元,但对其形成时代的认识存在分歧。笔者通过对豫西地区武当地体北部武当群上部杨坪组变质沉积岩和下部双台组变质中酸性火山岩锆石U-Pb年龄的测定,认为杨坪组变质沉积岩沉积物源主要由晚元古代(860~640Ma)和早元古代(2260~1800Ma)、少量晚太古代和中元古代地壳物质构成,与扬子陆块具有亲缘关系。沉积时代应晚于640Ma。变质中酸性火山岩形成时代为730~780Ma之间,峰值(755±6)Ma,与双台组新元古代变质基性火山岩为同期岩浆作用的产物,成因上推测与Rodinia超大陆裂解作用有关。 展开更多
关键词 武当群 锆石U-PB年龄 秦岭造山带 豫西 新元古代
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越南昆嵩地体三叠纪花岗岩岩石成因及其特提斯构造意义
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作者 李慧玲 钱鑫 +5 位作者 余小清 pham trung hieu 张菲菲 余永琪 徐畅 王岳军 《地球科学》 EI CAS CSCD 北大核心 2023年第4期1441-1460,共20页
昆嵩地体位于印支陆块的核部,记录了大量的印支期岩浆作用和构造热事件,是了解古特提斯洋演化及印支与华南陆块碰撞拼合过程的关键区域,但目前对该期岩浆事件的成因及其与北部长山带的关系未能得到有效厘定.对昆嵩地体绥安(Huyen Tuy An... 昆嵩地体位于印支陆块的核部,记录了大量的印支期岩浆作用和构造热事件,是了解古特提斯洋演化及印支与华南陆块碰撞拼合过程的关键区域,但目前对该期岩浆事件的成因及其与北部长山带的关系未能得到有效厘定.对昆嵩地体绥安(Huyen Tuy An)和胶寮(Chu Loan)地区的Van Canh花岗岩开展了岩相学、锆石U-Pb年代学、锆石原位Hf同位素和全岩地球化学分析,以限定其形成时代、岩石成因及构造环境.锆石U-Pb定年显示花岗岩样品的结晶年龄为244~239 Ma.该套样品包括了二长花岗岩和钾长花岗岩,均属于高钾钙碱性系列.它们的A/CNK值为1.03~1.21,为S型花岗岩.花岗岩均显示明显的Rb、Th和U富集,以及Nb、Sr、Zr和Ti的亏损,并具有强烈的Eu负异常(Eu/Eu*=0.24~0.56).锆石具有富集的原位Hf同位素组成(εH(f t)=−11.2~−0.7)以及古-中元古代的Hf二阶模式年龄(TDM2=1.98~1.31 Ga).研究表明该套中三叠世花岗岩是古元古代-中元古代变沉积岩部分熔融的产物,并伴有少量变火成岩的加入.研究结合区域地质资料表明昆嵩地体中三叠世Van Canh花岗岩的成因与马江古特提斯分支洋闭合之后的印支与华南陆块的碰撞拼合有关,形成于后碰撞阶段,进而证实了长山带向南可以延伸至昆嵩地体内部. 展开更多
关键词 印支陆块 越南昆嵩地体 中三叠世 S型花岗岩 古特提斯洋 后碰撞 地球化学
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