增强语义分割的网络模型PS-UNet

文章提出了一种提升上下文依赖关系的增强语义分割网络模型PS-UNet实现医学图像分割. PS-UNet将残差块、PCA模块和SPP模块融合到U-Net网络模型中，可获取更多的特征信息，从而提升分割效果.该模型既可以对器官轮廓粗分割又可以对视网膜血管和细胞精细分割.在公开的数据集上分别对肺部、视网膜血管和细胞分割进行了测试.实验结果表明，与当前先进网络模型相比，PS-UNet在所有实验中，性能均有所提升，其中肺部分割中准确率和灵敏度相对于U-Net网络模型分别提高了2.03%和2.24%,Dice相似系数达到了97.16%.     

采用超像素标注匹配的交通场景几何分割方法

针对交通场景逐像素标注方法计算复杂、模型训练耗时长的问题,提出了一种基于超像素标注匹配的交通场景几何分割方法。该方法无需进行模型训练,根据全局特征搜索一组待分割交通场景图像的相似图像集。对待分割图像进行超像素分割和超像素块特征提取,并利用朴素贝叶斯原理进行似然比计算,根据似然比在相似图像集中进行超像素块标注匹配以实现初次分割。利用初次分割结果计算出一元势,应用全连接条件随机场模型对初次分割结果进行优化。实验结果表明,与传统的逐像素标注方法相比,本文方法的分割正确率和平均召回率分别提高了4%和3%,能够有效地实现交通场景几何分割。     

基于双重相似度孪生网络的小样本实例分割

针对孪生网络在小样本数据集上的应用和优化问题,提出一种基于双重相似度计算和孪生网络的小样本实例分割模型。首先对传统孪生网络进行改进,将孪生网络与残差网络相结合,构建作为本模型骨干网络的孪生残差网络;然后在相似度计算阶段构建了具有两个子网络的双重相似度计算网络,分别用于计算场景图像与参考图像的空域相似度和频域相似度,并进行相似度特征融合;最后通过实例分割网络获得分割结果。此外,还引入Focal Loss损失函数来解决模型训练过程中正、负样本以及难、易样本的不均衡问题。在COCO数据集上的实验结果表明,本文方法的小样本实例分割性能要优于对比算法。     

基于深度学习的盾构隧道渗漏水病害混合样本集构建与精细分割

渗漏水病害是盾构隧道运营期间最为常见的一种表观病害，对隧道结构安全与周边地层稳定具有不利影响.基于深度学习的图像病害识别方法，构建了包含检测装置与人工巡检两种方式采集图像的混合样本集.以平均准确度为评估指标，训练得到Mask R-CNN深度学习模型的分割准确度达到0.447,优于原样本集(0.386)与扩容样本集(0.403).考虑隧道渗漏水病害形态复杂的特点以及不同病害间较大的特征差异，进一步采用条件卷积动态生成的分割模型参数代替Mask R-CNN模型中静态的模型参数，提高了模型的分割速度与精度.以每秒运算图像数量(Frames Per Second, FPS)为评估指标，模型分割速度由7FPS提升至10FPS,且分割结果与病害真实轮廓更为接近，从而有利于对渗漏水病害的严重程度进行量化分析.     

基于委员会查询和自步多样性学习的医学图像分割

由于拥有像素级标记的医学图像数量非常少,制约了卷积神经网络在医学图像分割任务上的应用,因此,该文提出了一种基于委员会查询的自步多样性学习算法,在训练数据有限的情况下提升医学图像分割模型的性能。该文所提算法结合了基于委员会查询的数据选择方法,实现动态地从易到难选择样本,对模型进行训练。同时,该算法通过应用仿射传播聚类,保证了数据选择的多样性,提升了图像分割模型的性能。为了验证所提算法框架的有效性,分别在3类医学图像分割任务的5个不同数据集任务上进行了实验,实验结果表明,该文所提算法可以显著提升分割性能。在使用相同数据的训练的情况下,相比于全监督学习,使用该文算法可以得到更高的Dice评估指标、表面距离和平均交并比值。     

基于帧间相关性的乳腺MRI三维分割

针对乳腺磁共振图像序列的肿瘤分割问题,提出一种基于超像素和改进C-V模型的三维全自动分割方法.该方法利用磁共振图像序列的帧间相关性,约束相邻帧图像的分割轮廓.采用超像素算法提取肿瘤的大致轮廓,再用改进的C-V水平集算法对可疑区域边缘进行优化,使其更接近肿瘤的实际边缘.将该方法及3种对比方法应用于89例乳腺MRI序列图像.以手动分割的轮廓为基准,该方法得到的平均重叠率为87.84%,,相比于C-V模型的58.90%,、超像素和水平集结合的76.36%,、K均值+C-V的83.62%,,有明显提升.实验结果表明,该方法的全自动分割结果对于肿瘤起始和终止帧图像具有较高的分割精度.     

基于VGG-F动态学习模型的苹果病虫害识别

为了提高自然环境下苹果病虫害的识别准确率和识别效率,提出了具有动态学习特征的VGG-F苹果病虫害识别模型。首先,依据常见的苹果病害和虫害类型构建图像数据集,同时采用Retinex算法对数据集中的含雾图像进行增强处理;然后选择网络层数较少的VGG-F网络模型作为迁移学习对象,并依据数据样本特性对重训练过程进行学习率动态调整,以及基于试验对比选取最佳动量值;最后,利用数据集对三种不同模型进行重训练和识别效果对比测试。数值测试结果表明,相比于原始VGG-F模型和深层模型VGG-19,文中模型将苹果病虫害识别准确率分别提升了5%和0.63%,且该模型的重训练时间最短,从而验证了文中苹果病虫害识别模型的有效性。     

一种不同色域空间下的无监督图像分割技术

针对图像分割有监督学习模型训练时间长、需要大量训练样本才能确保模型精度要求且样本标记费时费力的问题,提出了在不同色域空间下基于神经网络的无监督图像分割方法。首先将图像进行不同颜色空间模型转化,得到不同色域空间下图像的颜色表示;其次利用felz和quickshift方法,对转换后的图像进行粗粒度聚类,形成超像素结果,并对每个像素打上相应的标签;最后利用神经网络细粒度的图像特征分辨能力进行微调,得到最终的图像分割结果。该方法在公开的COD10K等数据集上选取了数据集进行验证,实验表明,文中方法能够对图像进行合理分割,且与有监督长时间训练过程相比,无监督的推理耗时大大缩短,速度显著提高。     

一种基于偏压场的水平集图像快速分割算法

提出了一种基于偏压场的水平集图像快速分割算法.运用偏压场估计图像局部统计信息,结合图像的全局信息和图像边缘信息建立新的能量函数,然后将此能量函数嵌入到水平集框架中,得到最终改进的分割模型.最后对合成图像和真实图像进行分割,并与其他4种模型对比,实验结果表明,提出的模型分割精度提高了20%以上,而且分割速度提高了2~5倍.     

基于双任务一致性的半监督深度学习医学图像分割方法

【目的】医学图像分割是医学图像分析中的一个重要内容。现有的大部分图像分割算法都是基于监督学习,而实际应用中医学图像标签难以获取,大量标注需依赖领域专家,费时费力。因此,提出一种双任务一致性的半监督医学图像分割模型。【方法】该模型采用一个编码器,两个解码器的网络结构,其中编码器和一个解码器实现图像分割,与另一个解码器实现图像重建。无标签数据通过一致性分割与重建任务得到的两个不同图像背景计算损失并优化网络参数。同时在网络的编码器部分加入注意力模块以更好地获取分割区域的空间位置信息,并使用锐化操作增加无标签数据重建输出的置信度。【结果】在肝脏和细胞数据集上IOU分别为0.953 6和0.821 0,相较于U Net提高了1.5%和4.82%;在眼底血管数据集上,SP值为0.983 0,与第二名相比提升了0.18%。【结论】本文模型与有监督方法和半监督方法相比,在医学图像分割的有效性和泛化性上有一定的性能提升,能有效解决数据集数量少、小病灶分割难度大的问题。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.