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Malignant triton tumor in the abdominal wall:A case report
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作者 Ho Jik Yang Donghyun Kim +1 位作者 won suk lee Sang-Ha Oh 《World Journal of Clinical Cases》 SCIE 2024年第8期1467-1473,共7页
BACKGROUND Malignant triton tumors(MTTs)comprise a subgroup of malignant peripheral nerve sheath tumors(MPNSTs)that exhibits rhabdomyosarcomatous differen-tiation and follow an aggressive course.MTTs are primarily loc... BACKGROUND Malignant triton tumors(MTTs)comprise a subgroup of malignant peripheral nerve sheath tumors(MPNSTs)that exhibits rhabdomyosarcomatous differen-tiation and follow an aggressive course.MTTs are primarily located along peripheral nerves.Cases of MTTs in the abdominal wall have not been reported.MTT has a poorer prognosis than classic MPNSTs,and accurate diagnosis necessitates a keen understanding of the clinical history and knowledge of its differential diagnosis intricacies.Treatment for MTTs mirrors that for MPNSTs and is predominantly surgical.CASE SUMMARY A 49-year-old woman presented with a subcutaneous mass in her lower abdo-minal wall and a pre-existing surgical scar that had grown slowly over 3-4 months before the consultation.She had previously undergone radical hysterectomy and concurrent chemo-radiotherapy for cervical cancer approximately 5 years prior to the consultation.Abdominal computed tomography(CT)showed a 1.3 cm midline mass in the lower abdomen with infiltration into the rectus abdominis muscle.There was no sign of metastasis(T1N0M0).An incisional biopsy identified sporadic MTT of the lower abdomen.A comprehensive surgical excision with a 3 cm margin inclusive of the peritoneum was executed.Subse-quently,the general surgeon utilized an approach akin to the open peritoneal onlay mesh technique.The patient underwent additional treatment with an excision shaped as a mini-abdominoplasty for the skin defect.No complications arose,and annual follow-up CTs did not show signs of recurrence or metastasis.CONCLUSION An abdominal MTT was efficaciously treated with extensive excision and abdominal wall reconstruction,eliminating the need for postoperative radiotherapy. 展开更多
关键词 Malignant triton tumor Abdominal wall Surgical excision RECONSTRUCTION Case report
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柑桔黄龙病的可见-近红外光谱特征 被引量:20
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作者 李修华 李民赞 +2 位作者 won suk lee Reza Ehsani Ashish Ratn Mishra 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2014年第6期1553-1559,共7页
柑桔黄龙病是一种以木虱为载体的细菌病原,目前还没有行之有效的治疗方法,对世界柑桔产业构成了严重的威胁。探索快速检测柑桔黄龙病的方法,对该病的诊断、评估及进一步的控制都具有重要意义。该研究采用了快速、无损的光谱方法对该病... 柑桔黄龙病是一种以木虱为载体的细菌病原,目前还没有行之有效的治疗方法,对世界柑桔产业构成了严重的威胁。探索快速检测柑桔黄龙病的方法,对该病的诊断、评估及进一步的控制都具有重要意义。该研究采用了快速、无损的光谱方法对该病害特征进行初步探索。实验针对健康及染病植株的叶片及冠层,分别在实验室条件及田间环境下测量了其可见-近红外光谱反射率,以分析寻找二者的光谱差异。对原始光谱数据进行了平滑、聚类平均等预处理,并求取了一阶微分以确定其红边位置(red edge position,REP)。为了应对一阶微分在REP处的多个波峰现象,采用了线性外插值法及拉格朗日插值法量化REP。研究结果显示,健康及染病样本的反射率在可见光、近红外具有明显的差异。相比于健康样本,染病样本因其呈现的黄化现象,使其反射率在可见光区较高;又因黄龙病菌会明显阻碍叶片对水分的吸收而使其反射率在近红外较低。REP同样显示了潜在的区分能力,其明显随着染病程度的加深逐渐向红波段移动。在染病程度差异较大的数据集中,REP平均值相差达20nm;而在染病程度差异较小的数据集中,阈值分割法的分类精度也高达90%以上,且线性外插值法的分类精度略高于拉格朗日插值法。本研究成果为利用光谱技术快速无损检测柑桔黄龙病提供了可靠的理论依据。 展开更多
关键词 柑桔黄龙病 光谱反射率 一阶微分 红边位置 插值法
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基于Vis-NIR光谱的柑橘叶片黄龙病检测及其光谱特性研究 被引量:13
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作者 马淏 吉海彦 won suk lee 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2014年第10期2713-2718,共6页
黄龙病作为柑橘类水果最具毁灭性的疾病之一,目前尚无有效的治愈手段,因此疾病预防成为已知的唯一有效方法。基于四种柑橘叶片(健康叶片、黄龙病叶片、铁缺乏叶片及氮缺乏叶片)VIS-NIR的反射光谱详细讨论了黄龙病的辨别方法以及在判别... 黄龙病作为柑橘类水果最具毁灭性的疾病之一,目前尚无有效的治愈手段,因此疾病预防成为已知的唯一有效方法。基于四种柑橘叶片(健康叶片、黄龙病叶片、铁缺乏叶片及氮缺乏叶片)VIS-NIR的反射光谱详细讨论了黄龙病的辨别方法以及在判别模型中光谱特征值的提取方法。在两类判别分析的特征值提取方法中,判别值(discriminability)运算的引入,为特征值提取提供了一个可靠依据,判别值越大表明光谱差异性越大。以被选特征值建立的Fisher线性判别分析模型,黄龙病与健康、铁缺乏、氮缺乏叶片的分类判别预测准确率分别都超过了90%,分类效果符合预期。最后,又讨论了分类树(classificationTree)在多类判别中的应用。通过对柑橘叶片原始反射谱,一阶导数谱及被选特征值分别建立分类模型,四种柑橘叶片平均预测准确度都超过88%,尤其是基于特征值的分类结果更是超过94%,验证了在多类判别中检测柑橘黄龙病的可行性及特征值提取的重要性。结合传统分类方法(k-NN,Bayesian)的结果分析,特征值作为输入变量的分类结果明显要优于原始光谱,证实了特征值选取的正确性,并为将来基于光谱特征值开发多光谱成像技术检测黄龙病打下坚实的基础。 展开更多
关键词 黄龙病 判别值 FISHER线性判别 分类树 近红外光谱
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基于高光谱成像技术应用光谱及纹理特征识别柑橘黄龙病(英文) 被引量:6
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作者 马淏 吉海彦 won suk lee 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2016年第7期2344-2350,共7页
讨论了基于高光谱成像技术光谱及纹理特征在识别早期柑橘黄龙病中的应用。使用一套近地高光谱成像系统采集了176枚柑橘叶片的高光谱图像作为实验样品,其中健康叶片60枚,黄龙病叶片60枚,缺锌叶片56枚。手工选取每幅叶片高光谱图像的病斑... 讨论了基于高光谱成像技术光谱及纹理特征在识别早期柑橘黄龙病中的应用。使用一套近地高光谱成像系统采集了176枚柑橘叶片的高光谱图像作为实验样品,其中健康叶片60枚,黄龙病叶片60枚,缺锌叶片56枚。手工选取每幅叶片高光谱图像的病斑位置作为样品感兴趣区域(regions of interest,ROI),计算其平均光谱反射率,并以此作为样品的反射光谱,光谱范围为396~1 010nm。样品光谱分别经过主成分分析(PXA)及连续投影算法(SPA)进行数据降维,再结合最小二乘支持向量机(LS-SVM)分类器建立分类模型。相比原始光谱,由PCA选取的前四个主成分及SPA选取的一组最佳波长组合(630.4,679.4,749.4和899.9 nm)建立的模型拥有更好的分类识别能力,其对三类柑橘叶片平均预测准确率分别为89.7%和87.4%。同时,从被选四个波长的每幅灰度图像中提取6个灰度直方图的纹理特征以及9个灰度共生矩阵的纹理特征再次构建分类模型。经SPA优选的10个纹理特征值进一步提高了分类效果,对三类柑橘叶片的识别正确率达到了100%,93.3%和92.9%。实验结果表明,同时包含光谱信息及空间纹理信息的高光谱图像在柑橘黄龙病的识别中显示了很大的潜力。 展开更多
关键词 柑橘黄龙病 高光谱成像 分类 纹理特征 连续投影算法
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Detection of Apple Marssonina Blotch with PLSR, PCA, and LDA Using Outdoor Hyperspectral Imaging 被引量:3
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作者 Soo Hyun Park Youngki Hong +2 位作者 Mubarakat Shuaibu Sangcheol Kim won suk lee 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2020年第4期1309-1314,共6页
In this study, hyperspectral images were used to detect a fungal disease in apple leaves called Marssonina blotch(AMB). Estimation models were built to classify healthy, asymptomatic and symptomatic classes using part... In this study, hyperspectral images were used to detect a fungal disease in apple leaves called Marssonina blotch(AMB). Estimation models were built to classify healthy, asymptomatic and symptomatic classes using partial least squares regression(PLSR), principal component analysis(PCA), and linear discriminant analysis(LDA) multivariate methods. In general, the LDA estimation model performed the best among the three models in detecting AMB asymptomatic pixels, while all the models were able to detect the symptomatic class. LDA correctly classified asymptomatic pixels and LDA model predicted them with an accuracy of 88.0%. An accuracy of 91.4% was achieved as the total classification accuracy. The results from this work indicate the potential of using the LDA estimation model to identify asymptomatic pixels on leaves infected by AMB. 展开更多
关键词 APPLE Marssonina blotch HYPERSPECTRAL IMAGING PLSR PCA LDA
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SUBic:A Scalable Unsupervised Framework for Discovering High Quality Biclusters
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作者 Jooil lee Yanhua Jin won suk lee 《Journal of Computer Science & Technology》 SCIE EI CSCD 2013年第4期636-646,共11页
A biclustering algorithm extends conventional clustering techniques to extract all of the meaningful subgroups of genes and conditions in the expression matrix of a microarray dataset. However, such algorithms are ver... A biclustering algorithm extends conventional clustering techniques to extract all of the meaningful subgroups of genes and conditions in the expression matrix of a microarray dataset. However, such algorithms are very sensitive to input parameters and show poor scalability. This paper proposes a scalable unsupervised biclustering framework, SUBic, to find high quality constant-row biclusters in an expression matrix effectively. A one-dimensional clustering algorithm is proposed to partition the attributes, that is, columns of an expression matrix into disjoint groups based on the similarity of expression values. These groups form a set of short transactions and are used to discover a set of frequent itemsets each of which corresponds to a bicluster. However, a bicluster may include any attribute whose expression value is not similar enough to others, so a bicluster refinement is used to enhance the quality of a bicluster by removing those attributes based on its distribution of expression values. The performance of the proposed method is comparatively analyzed through a series of experiments on synthetic and real datasets. 展开更多
关键词 BICLUSTERING CLUSTERING expression matrix frequent itemset sub-matrix
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Feature extraction of hyperspectral images for detecting immature green citrus fruit
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作者 Yongjun DING won suk lee Minzan LI 《Frontiers of Agricultural Science and Engineering》 2018年第4期475-484,共10页
At an early immature growth stage of citrus, a hyperspectral camera of 369–1042 nm was employed to acquire 30 hyperspectral images in order to detect immature green fruit within citrus trees under natural illuminatio... At an early immature growth stage of citrus, a hyperspectral camera of 369–1042 nm was employed to acquire 30 hyperspectral images in order to detect immature green fruit within citrus trees under natural illumination conditions. First, successive projections algorithm(SPA) were implemented to select 677, 804,563, 962, and 405 nm wavebands and to construct multispectral images from the original hyperspectral images for further processing. Then, histogram threshold segmentation using NDVI of 804 and 677 nm was implemented to remove image backgrounds. Three slope parameters, calculated from the pairs 405 and 563 nm, 563 and 677 nm, and 804 and 962 nm were used to construct a classifier to identify the potential citrus fruit. Then, a marker-controlled watershed segmentation based on wavelet transform was applied to obtain potential fruit areas.Finally, a green fruit detection model was constructed according to Grey Level Co-occurrence Matrix(GLCM)texture features of the independent areas. Three supervised classifiers, logistic regression, random forest and support vector machine(SVM) were developed using texture features. The detection accuracies were 79%, 75%, and 86% for the logistic regression, random forest, and SVM models, respectively. The developed algorithm showed a great potential for identifying immature green citrus for an early yield estimation. 展开更多
关键词 HYPERSPECTRAL green CITRUS image processing FRUIT detection precision AGRICULTURE YIELD mapping
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