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Automated body composition analysis system based on chest CT for evaluating content of muscle and adipose
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作者 YANG Jie LIU Yanli +2 位作者 CHEN Xiaoyan CHEN Tianle LIU Qi 《中国医学影像技术》 CSCD 北大核心 2024年第8期1242-1248,共7页
Objective To establish a body composition analysis system based on chest CT,and to observe its value for evaluating content of chest muscle and adipose.Methods T7—T8 layer CT images of 108 pneumonia patients were col... Objective To establish a body composition analysis system based on chest CT,and to observe its value for evaluating content of chest muscle and adipose.Methods T7—T8 layer CT images of 108 pneumonia patients were collected(segmented dataset),and chest CT data of 984 patients were screened from the COVID 19-CT dataset(10 cases were randomly selected as whole test dataset,the remaining 974 cases were selected as layer selection dataset).T7—T8 layer was classified based on convolutional neural network(CNN)derived networks,including ResNet,ResNeXt,MobileNet,ShuffleNet,DenseNet,EfficientNet and ConvNeXt,then the accuracy,precision,recall and specificity were used to evaluate the performance of layer selection dataset.The skeletal muscle(SM),subcutaneous adipose tissue(SAT),intermuscular adipose tissue(IMAT)and visceral adipose tissue(VAT)were segmented using classical fully CNN(FCN)derived network,including FCN,SegNet,UNet,Attention UNet,UNET++,nnUNet,UNeXt and CMUNeXt,then Dice similarity coefficient(DSC),intersection over union(IoU)and 95 Hausdorff distance(HD)were used to evaluate the performance of segmented dataset.The automatic body composition analysis system was constructed based on optimal layer selection network and segmentation network,the mean absolute error(MAE),root mean squared error(RMSE)and standard deviation(SD)of MAE were used to evaluate the performance of automatic system for testing the whole test dataset.Results The accuracy,precision,recall and specificity of DenseNet network for automatically classifying T7—T8 layer from chest CT images was 95.06%,84.83%,92.27%and 95.78%,respectively,which were all higher than those of the other layer selection networks.In segmentation of SM,SAT,IMAT and overall,DSC and IoU of UNet++network were all higher,while 95HD of UNet++network were all lower than those of the other segmentation networks.Using DenseNet as the layer selection network and UNet++as the segmentation network,MAE of the automatic body composition analysis system for predicting SM,SAT,IMAT,VAT and MAE was 27.09,6.95,6.65 and 3.35 cm 2,respectively.Conclusion The body composition analysis system based on chest CT could be used to assess content of chest muscle and adipose.Among them,the UNet++network had better segmentation performance in adipose tissue than SM. 展开更多
关键词 body composition THORAX muscle skeletal adipose tissue deep learning tomography X-ray computed
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Under "Integration of Doing, Learning and Teaching", Research on the Project-Based Teaching Innovation of "Landscape Planning and Design"
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作者 Peiming Du Minghua Lu 《Journal of Educational Theory and Management》 2017年第1期60-64,共5页
Based on the research on the project course theory of "integration of theory and practice" in higher vocational education and the analysis of practical teaching in colleges and universities at home and abroa... Based on the research on the project course theory of "integration of theory and practice" in higher vocational education and the analysis of practical teaching in colleges and universities at home and abroad, combined with literature research, case analysis, system theory and other research methods, the project-based teaching goal, model, content and means of "integration of doing, learning and teaching" in higher vocational education is explored, and the project-based teaching model of "Landscape Planning and Design" is discussed combined with the application of information-based teaching methods. So as to provide references for carrying out the project-based teaching in similar courses in higher vocational colleges and really achieve docking the actual post requirements with the course to provide the basis for achieving the purpose of cultivating skilled talents in higher vocational education. 展开更多
关键词 INTEGRATION of doing learning and TEACHING LandSCAPE planning and design PROJECT-BASED RESEARCH on TEACHING innovation
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Effect of different levels of dietary zinc supplementation on body weight and learning ability in rats
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作者 朱虹 李积胜 《武警医学院学报》 CAS 2004年第3期169-173,共5页
To investigate the effect of increasing dietary zinc supplementation on body weight and learning ability in rats.Zinc supplemental diet contained 200, 400, 600, 800 or 1 600 mg/kg zinc,respectively.Y-labyrinth test wa... To investigate the effect of increasing dietary zinc supplementation on body weight and learning ability in rats.Zinc supplemental diet contained 200, 400, 600, 800 or 1 600 mg/kg zinc,respectively.Y-labyrinth test was applied to exam the learning and memory function of rats.Significantly greater weight gain was observed in rats fed with 400 mg/kg zinc diet than in rats fed with 200 mg/kg zinc diet(P<0.05). During the early experiment, lower weight increments were notably observed in rats with 600, 800 or 1 600 mg/kg zinc supplementation than that in control group, respectively. But the influence on weight relief became weaker in pace with time on the whole. Learning and memory function for rats were strikingly improved at level of 200 mg/kg zinc diet compared with the control level(P<0.05), and were damaged in varying degrees at higher(except 1 600 mg/kg) zinc supplementation levels in feeds, among which,800 mg/kg zinc dosage had produced obviously lesion for learning ability in rats compared with normal, 200 or 1 600 mg/kg zinc levels(P<0.05, respectively).[Conclusion]These results suggest that different levels of zinc supplementation have some incompletely parallel effects on the growth, memory and capacity to learn in rats. 展开更多
关键词 剂量 补锌 大鼠 体重 学习记忆
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Comparison and development of advanced machine learning tools to predict nonalcoholic fatty liver disease:An extended study 被引量:3
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作者 Yuan-Xing Liu Xi Liu +9 位作者 Chao Cen Xin Li Ji-Min Liu Zhao-Yan Ming Song-Feng Yu Xiao-Feng Tang Lin Zhou Jun Yu Ke-Jie Huang Shu-Sen Zheng 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2021年第5期409-415,共7页
Background:Nonalcoholic fatty liver disease(NAFLD)is a public health challenge and significant cause of morbidity and mortality worldwide.Early identification is crucial for disease intervention.We recently proposed a... Background:Nonalcoholic fatty liver disease(NAFLD)is a public health challenge and significant cause of morbidity and mortality worldwide.Early identification is crucial for disease intervention.We recently proposed a nomogram-based NAFLD prediction model from a large population cohort.We aimed to explore machine learning tools in predicting NAFLD.Methods:A retrospective cross-sectional study was performed on 15315 Chinese subjects(10373 training and 4942 testing sets).Selected clinical and biochemical factors were evaluated by different types of machine learning algorithms to develop and validate seven predictive models.Nine evaluation indicators including area under the receiver operating characteristic curve(AUROC),area under the precision-recall curve(AUPRC),accuracy,positive predictive value,sensitivity,F1 score,Matthews correlation coefficient(MCC),specificity and negative prognostic value were applied to compare the performance among the models.The selected clinical and biochemical factors were ranked according to the importance in prediction ability.Results:Totally 4018/10373(38.74%)and 1860/4942(37.64%)subjects had ultrasound-proven NAFLD in the training and testing sets,respectively.Seven machine learning based models were developed and demonstrated good performance in predicting NAFLD.Among these models,the XGBoost model revealed the highest AUROC(0.873),AUPRC(0.810),accuracy(0.795),positive predictive value(0.806),F1 score(0.695),MCC(0.557),specificity(0.909),demonstrating the best prediction ability among the built models.Body mass index was the most valuable indicator to predict NAFLD according to the feature ranking scores.Conclusions:The XGBoost model has the best overall prediction ability for diagnosing NAFLD.The novel machine learning tools provide considerable beneficial potential in NAFLD screening. 展开更多
关键词 Nonalcoholic fatty liver disease Machine learning Population screening Prediction model body mass index
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The Experience of Setting up a New Learning Environment Model in Management Education: Challenges and Frustrations
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作者 Jorge A. Santos Simone Martins 《Chinese Business Review》 2012年第8期730-739,共10页
The aim of this paper is to describe and to reflect on the experience of the authors in setting up a new model of learning environment in management education in a University in Brazil, which was initially called Mana... The aim of this paper is to describe and to reflect on the experience of the authors in setting up a new model of learning environment in management education in a University in Brazil, which was initially called Management Practice Laboratory (MPL). The MPL environment was conceived as a physical and conceptual space where students could learn and practice the principles and techniques of working in organizations in its three levels operational, tactical, and strategic. The foundations of the project come from social constructivist perspective on learning, from experiential learning literature and from researches that call for a new epistemological ground in management learning. In this paper, the authors will stress some challenges and frustrations with the project since these could be helpful to those interested in similar initiatives. Due to limited space, only two challenges will be stressed: (1) the construction of legitimacy for the project; and (2) the persistent dissonance between theory and practice. The authors conclude that there is room for innovation in the way management is taught and learned in universities since one shows courage to overcome the challenges and frustrations one will certainly deal with 展开更多
关键词 learning environments management education simulations practice laboratory experiential learning learning by doing
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Learning by Doing Effect in North South Trade under the Global Value Chains: An Empirical Analysis of Various Industries in the U.S.
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作者 Lin Kong 《International Journal of Technology Management》 2013年第12期25-28,共4页
This paper studies the division of labor and economic development under global value chains in North South trade by mainly investigating the changes of production hours and cost per unit along with more and more outpu... This paper studies the division of labor and economic development under global value chains in North South trade by mainly investigating the changes of production hours and cost per unit along with more and more output and increasing trade value in several industries in the U.S., because the U. S. is at the leading position in the division of labor by global value chains. The empirical evidence reveals that more international outsourcing, there will be more detailed division of labor, and the industry unit production time and production cost will show more declining trend year by year. This is consistent with that the global value chains and the outsourcing play more and more important roles in the international division of labor and economic growth in both developed and developing countries, and helps explain the integration of workforce across countries in the global value chains. 展开更多
关键词 Global Value Chains North South Trade Division of Labor learning by doing INDUSTRIES
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Learning by doing: Software project management course education
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作者 HUANG Long-jun DAI Li-pin GUO Bin LEI Gang 《通讯和计算机(中英文版)》 2009年第9期35-38,61,共5页
关键词 软件项目管理 课程教育 教学模式 学习 有效管理 软件编程 培养目标 学生
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“Learning by Doing”教学模式的探索 被引量:21
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作者 何宗键 覃文忠 《计算机教育》 2005年第12期26-27,共2页
"Learning by Doing"是由美国卡内基·梅隆大学率先提出的一种旨在强化工程学科的学生全面实践能力和工程素养的教学模式。其目的就是让学生在"做"的过程中,深刻掌握相关的技术和技能,获得远超过课堂教学的教... "Learning by Doing"是由美国卡内基·梅隆大学率先提出的一种旨在强化工程学科的学生全面实践能力和工程素养的教学模式。其目的就是让学生在"做"的过程中,深刻掌握相关的技术和技能,获得远超过课堂教学的教学效果。本文首先介绍了"LearningbyDoing"的概念及作用,然后详细讨论了在"WindowsCE嵌入式系统"课程中实施"LearningbyDoing"的具体做法以及经验得失。 展开更多
关键词 learning by doing 嵌入式系统 教学改革
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Learning-by-doing教学模式在安全系统工程教学中的应用 被引量:10
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作者 樊运晓 《中国安全科学学报》 CAS CSCD 2007年第7期89-92,共4页
安全系统工程课程是安全工程专业的专业基础课,其教学效果的好坏对后续课程的学习以及日后所从事的工作至关重要。因而该课程教学方法的运用选择值得深思。笔者分析了安全工程专业中安全系统工程课程的特点和教学中存在的问题,引用learn... 安全系统工程课程是安全工程专业的专业基础课,其教学效果的好坏对后续课程的学习以及日后所从事的工作至关重要。因而该课程教学方法的运用选择值得深思。笔者分析了安全工程专业中安全系统工程课程的特点和教学中存在的问题,引用learning-by-doing的教学模式并在教学中加以应用,提出"通过授课得到答案——学会一个解,通过案例讨论得到方法——学会一个方法,通过实践模拟学会学习——学会找到个方法,通过总结学会融会贯通"的安全系统工程教学模式,收到了较好的教学效果。 展开更多
关键词 安全工程 专业 安全系统工程 教学模式 learning—by—doing(做中学)
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“Flash动画设计”课程“Learning by doing”教学法探索 被引量:5
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作者 于丽杰 周冠玲 《计算机教育》 2010年第3期85-87,共3页
本文针对"Flash动画设计"的课程特点引入"Learningbydoing"教学理念,提出"简单实例掌握基本技能→案例讨论学会分析方法→模拟实践学会找到方法→总结经验融会贯通同时实现创新提高"的教学模式,在教学实... 本文针对"Flash动画设计"的课程特点引入"Learningbydoing"教学理念,提出"简单实例掌握基本技能→案例讨论学会分析方法→模拟实践学会找到方法→总结经验融会贯通同时实现创新提高"的教学模式,在教学实践中取得了良好的效果。 展开更多
关键词 FLASH 做中学 教学法
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基于Learning-by-doing的计算机系统结构课程改革 被引量:2
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作者 黄彩霞 徐惠 《计算机教育》 2011年第18期23-26,共4页
在计算机系统结构的课程教学中,引入由卡内基.梅隆大学提出的"Learning-by-doing"这一适用于工程教学的行之有效的先进教学理念是新教学模式的一种积极探索。文章围绕基于"Learning-by-doing"教学法的计算机系统结... 在计算机系统结构的课程教学中,引入由卡内基.梅隆大学提出的"Learning-by-doing"这一适用于工程教学的行之有效的先进教学理念是新教学模式的一种积极探索。文章围绕基于"Learning-by-doing"教学法的计算机系统结构课程改革实施的前期准备、遇到的问题,具体解决方案等环节进行了讨论和分析。 展开更多
关键词 learning-BY-doing 教学模式 教学实践
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具有不完全技术外部性的随机Learning-by-Doing模型及解法 被引量:1
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作者 王海军 胡适耕 《华中师范大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第3期359-362,共4页
提出适用于随机Learning-by-Doing模型的"附加效用"值函数解法,并用此方法求解具有不完全技术外部性的随机learning-by-doing模型,得到了均衡时的经济增长路径、消费—资本比和值函数,讨论了技术外部性对私人资本回报率、消... 提出适用于随机Learning-by-Doing模型的"附加效用"值函数解法,并用此方法求解具有不完全技术外部性的随机learning-by-doing模型,得到了均衡时的经济增长路径、消费—资本比和值函数,讨论了技术外部性对私人资本回报率、消费倾向、均值经济增长率和个体福利的影响. 展开更多
关键词 1earning—by-doing 内生增长 技术外部性 “附加效用”值函数法
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“嵌入式系统程序设计实习”教学改革——探索“Learning by Doing”教学模式 被引量:2
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作者 石林祥 贺海晖 《福建电脑》 2009年第8期208-208,183,共2页
"Learning by Doing"是一种旨在强化工程学科的学生全面实践能力和工程素养的教学模式。其目的就是让学生在"做"的过程中,深刻掌握相关的技术和技能,获得远超过课堂教学的教学效果。本文阐述了在"嵌入式系统... "Learning by Doing"是一种旨在强化工程学科的学生全面实践能力和工程素养的教学模式。其目的就是让学生在"做"的过程中,深刻掌握相关的技术和技能,获得远超过课堂教学的教学效果。本文阐述了在"嵌入式系统程序设计实习"课程中实施"Learning by Doing"的具体方法以及一些经验得失。 展开更多
关键词 嵌入式系统程序设计实习 教学改革 learning by doing
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基于Learning-by-doing的不确定经济增长与财政政策研究
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作者 王海军 陈勇 《浙江社会科学》 CSSCI 北大核心 2008年第12期2-6,共5页
本文研究基于learning-by-doing的随机增长模型,得到了均衡时的经济增长路径、债券回报率、资产组合份额和消费-资本比,分析财政政策对长期经济增长、资产组合选择、个体消费倾向和个体福利的影响,探讨最优的财政政策。
关键词 随机增长 财政政策 learning—by—doing 财富补贴
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“干中学(Learning by Doing)”——浅议课堂教学方法改革 被引量:9
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作者 徐玲玲 《重庆工学院学报》 2006年第8期150-151,167,共3页
提出了“干中学”的新型课堂教学观.阐释了学生通过“干中学”能主动参与课堂教学,成为教学的真正主体.从传统课堂教学和新型课堂教学的比较,说明新型的师生关系是双向的、交互的,教师作为课堂教学的组织者和协调者,在教学中只能起“主... 提出了“干中学”的新型课堂教学观.阐释了学生通过“干中学”能主动参与课堂教学,成为教学的真正主体.从传统课堂教学和新型课堂教学的比较,说明新型的师生关系是双向的、交互的,教师作为课堂教学的组织者和协调者,在教学中只能起“主导”作用. 展开更多
关键词 干中学 传统课堂教学 新型课堂教学
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一个多资本的Learning-by-doing模型
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作者 雷冬霞 胡适耕 吴付科 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2001年第3期103-106,共4页
考虑一个多资本投入的一般Learning by doing模型 .该模型技术进步的增长率由经济发展过程内生地决定 .当技术对资本为递减规模回报时 ,该经济仅有唯一正的均衡点 .运用单调动力系统理论论证了此模型的稳定性问题 。
关键词 Learnging-by-doing模型 单调动力系统 均衡状态 收敛速度 多资本投入 资本积累
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Learning by doing方法在移动平台应用开发课中的应用
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作者 李涵 《实验室科学》 2018年第6期111-113,共3页
"嵌入式移动平台应用开发"课程是电子信息科学与技术专业的专业课,以培养学生的嵌入式软件开发能力为目的。将Learning by doing教学模式应用到嵌入式移动平台应用开发课程中,通过改革授课方式、教学内容组织以及考核方式,使... "嵌入式移动平台应用开发"课程是电子信息科学与技术专业的专业课,以培养学生的嵌入式软件开发能力为目的。将Learning by doing教学模式应用到嵌入式移动平台应用开发课程中,通过改革授课方式、教学内容组织以及考核方式,使学生在做中理解所学的知识,融会贯通,实操能力和编程动手能力得到提高。通过实践,取得了良好的教学效果,培养了学生的创新精神和解决实际问题的能力。 展开更多
关键词 learning by doing 项目驱动 教学改革 嵌入式移动平台应用开发
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Machine Learning Approaches to Detect DoS and Their Effect on WSNs Lifetime
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作者 Raniyah Wazirali Rami Ahmad 《Computers, Materials & Continua》 SCIE EI 2022年第3期4921-4946,共26页
Energy and security remain the main two challenges in Wireless Sensor Networks(WSNs).Therefore,protecting these WSN networks from Denial of Service(DoS)and Distributed DoS(DDoS)is one of the WSN networks security task... Energy and security remain the main two challenges in Wireless Sensor Networks(WSNs).Therefore,protecting these WSN networks from Denial of Service(DoS)and Distributed DoS(DDoS)is one of the WSN networks security tasks.Traditional packet deep scan systems that rely on open field inspection in transport layer security packets and the open field encryption trend are making machine learning-based systems the only viable choice for these types of attacks.This paper contributes to the evaluation of the use machine learning algorithms in WSN nodes traffic and their effect on WSN network life time.We examined the performance metrics of different machine learning classification categories such asK-Nearest Neighbour(KNN),Logistic Regression(LR),Support Vector Machine(SVM),Gboost,Decision Tree(DT),Na飗e Bayes,Long Short Term Memory(LSTM),and Multi-Layer Perceptron(MLP)on aWSN-dataset in different sizes.The test results proved that the statistical and logical classification categories performed the best on numeric statistical datasets,and the Gboost algorithm showed the best performance compared to different algorithms on average of all performance metrics.The performance metrics used in these validations were accuracy,F1-score,False Positive Ratio(FPR),False Negative Ratio(FNR),and the training execution time.Moreover,the test results showed the Gboost algorithm got 99.6%,98.8%,0.4%0.13%in accuracy,F1-score,FPR,and FNR,respectively.At training execution time,it obtained 1.41 s for the average of all training time execution datasets.In addition,this paper demonstrated that for the numeric statistical data type,the best results are in the size of the dataset ranging from3000 to 6000 records and the percentage between categories is not less than 50%for each category with the other categories.Furthermore,this paper investigated the effect of Gboost on the WSN lifetime,which resulted in a 32%reduction compared to other Gboost-free scenarios. 展开更多
关键词 WSN intrusion detection machine learning DoS attack WSN security WSN lifetime
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基于3D Body软件的混合模式在放射肿瘤学教学中的应用
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作者 马岚 王亚利 +5 位作者 杨彭涛 李丹 张扬 包兴 李毅 潘纪元 《医学教育研究与实践》 2024年第6期792-797,804,共7页
目的分析基于3D Body软件的线上线下混合式模式应用于放射肿瘤学教学中的效果。方法选取两个阶段参与放射肿瘤学教学的实习生,其中2022年1月—12月的32名实习生(对照组)采用传统带教模式;2023年1月—12月的32名实习生(观察组)采用基于3D... 目的分析基于3D Body软件的线上线下混合式模式应用于放射肿瘤学教学中的效果。方法选取两个阶段参与放射肿瘤学教学的实习生,其中2022年1月—12月的32名实习生(对照组)采用传统带教模式;2023年1月—12月的32名实习生(观察组)采用基于3D Body软件的线上线下混合式教学模式,评估两组放射肿瘤学教学效果。结果观察组理论考核、实践操作考核、平时成绩均高于对照组,差异有统计学意义(P<0.05);观察组专业技术(包括靶区勾画、制定计划、计划评估,计划验证)能力评分均高于对照组,差异有统计学意义(P<0.05);观察组评判性思维能力高于对照组,差异有统计学意义(P<0.05);观察组实习生的自我能力评价分值高于对照组,差异有统计学意义(P<0.05);观察组实习生对教学模式满意度评价分值高于对照组,差异有统计学意义(P<0.05)。结论放射肿瘤学教学实践中,相比传统带教模式,基于3D Body软件的线上线下混合式教学模式具有明显改善教学效果、提高实习生专业技术能力与评价满意度的作用。 展开更多
关键词 3D body软件 线上线下混合式教学模式 放射肿瘤学 临床教学
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Uninvolved liver dose prediction in stereotactic body radiation therapy for liver cancer based on the neural network method
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作者 Huai-Wen Zhang You-Hua Wang +1 位作者 Bo Hu Hao-Wen Pang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第10期4146-4156,共11页
BACKGROUND The quality of a radiotherapy plan often depends on the knowledge and expertise of the plan designers.AIM To predict the uninvolved liver dose in stereotactic body radiotherapy(SBRT)for liver cancer using a... BACKGROUND The quality of a radiotherapy plan often depends on the knowledge and expertise of the plan designers.AIM To predict the uninvolved liver dose in stereotactic body radiotherapy(SBRT)for liver cancer using a neural network-based method.METHODS A total of 114 SBRT plans for liver cancer were used to test the neural network method.Sub-organs of the uninvolved liver were automatically generated.Correlations between the volume of each sub-organ,uninvolved liver dose,and neural network prediction model were established using MATLAB.Of the cases,70%were selected as the training set,15%as the validation set,and 15%as the test set.The regression R-value and mean square error(MSE)were used to evaluate the model.RESULTS The volume of the uninvolved liver was related to the volume of the corresponding sub-organs.For all sets of Rvalues of the prediction model,except for D_(n0)which was 0.7513,all R-values of D_(n10)-D_(n100)and D_(nmean)were>0.8.The MSE of the prediction model was also low.CONCLUSION We developed a neural network-based method to predict the uninvolved liver dose in SBRT for liver cancer.It is simple and easy to use and warrants further promotion and application. 展开更多
关键词 Dose prediction Sub-organ Machine learning Stereotactic body radiotherapy Liver cancer
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