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81.
Guang-Ri Piao & Hyung-Chun Lee 《East Asian journal on applied mathematics.》2024,14(3):507-529
An efficient real-time computational method for a feedback control problemof the Boussinesq equations is studied. We consider a simple and effective feedback control law based on the relationship between the control and adjoint variables in the optimality system. We investigate a closure type modeling in reduced order model (ROM) ofthis problem for real-time computing. In order to improve the existing well-known POD-ROM method, the deep learning technique, which is currently being actively researched,is studied and applied. Computational results presented show that the suggested methods work well. 相似文献
82.
83.
Breast cancer is one of the most common types of cancer in women, and histopathological imaging is considered the gold standard for its diagnosis. However, the great complexity of histopathological images and the considerable workload make this work extremely time-consuming, and the results may be affected by the subjectivity of the pathologist. Therefore, the development of an accurate, automated method for analysis of histopathological images is critical to this field. In this article, we propose a deep learning method guided by the attention mechanism for fast and effective classification of haematoxylin and eosin-stained breast biopsy images. First, this method takes advantage of DenseNet and uses the feature map's information. Second, we introduce dilated convolution to produce a larger receptive field. Finally, spatial attention and channel attention are used to guide the extraction of the most useful visual features. With the use of fivefold cross-validation, the best model obtained an accuracy of 96.47% on the BACH2018 dataset. We also evaluated our method on other datasets, and the experimental results demonstrated that our model has reliable performance. This study indicates that our histopathological image classifier with a soft attention-guided deep learning model for breast cancer shows significantly better results than the latest methods. It has great potential as an effective tool for automatic evaluation of digital histopathological microscopic images for computer-aided diagnosis. 相似文献
84.
针对增量式运动恢复结构算法在多视图几何三维重建算法中运行效率低的问题,提出了一种基于AKAZE算法的多视图几何三维重建方法。首先对利用摄像机获得的目标图像使用AKAZE算法检测特征并匹配,并使用随机抽取一致性算法和三视图约束剔除弱匹配图像。然后根据匹配图间的相对位姿参数,通过最小二乘法解算全局旋转参数,并利用三视图约束关系求解全局位移参数。最后进行一次光束法平差优化。实验结果表明,该算法在改善重建效果的基础上提高了处理效率,能够满足快速处理的需求。 相似文献
85.
Yutsung Tsai Zhaodong Chu Yimo Han Chih‐Piao Chuu Di Wu Alex Johnson Fei Cheng Mei‐Yin Chou David A. Muller Xiaoqin Li Keji Lai Chih‐Kang Shih 《Advanced materials (Deerfield Beach, Fla.)》2017,29(41)
Semiconductor heterostructures have played a critical role as the enabler for new science and technology. The emergence of transition‐metal dichalcogenides (TMDs) as atomically thin semiconductors has opened new frontiers in semiconductor heterostructures either by stacking different TMDs to form vertical heterojunctions or by stitching them laterally to form lateral heterojunctions via direct growth. In conventional semiconductor heterostructures, the design of multijunctions is critical to achieve carrier confinement. Analogously, successful synthesis of a monolayer WS2/WS2(1?x )Se2x /WS2 multijunction lateral heterostructure via direct growth by chemical vapor deposition is reported. The grown structures are characterized by Raman, photoluminescence, and annular dark‐field scanning transmission electron microscopy to determine their lateral compositional profile. More importantly, using microwave impedance microscopy, it is demonstrated that the local photoconductivity in the alloy region can be tailored and enhanced by two orders of magnitude over pure WS2. Finite element analysis confirms that this effect is due to the carrier diffusion and confinement into the alloy region. This work exemplifies the technological potential of atomically thin lateral heterostructures in optoelectronic applications. 相似文献
86.
Kok Hong Tan Fang Sheng Lim Alfred Zhen Yang Toh Xia‐Xi Zheng Chang Fu Dee Burhanuddin Yeop Majlis Siang‐Piao Chai Wei Sea Chang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(20)
Observation of visible light trapping in zinc oxide (ZnO) nanorods (NRs) correlated to the optical and photoelectrochemical properties is reported. In this study, ZnO NR diameter and c‐axis length respond primarily at two different regions, UV and visible light, respectively. ZnO NR diameter exhibits UV absorption where large ZnO NR diameter area increases light absorption ability leading to high efficient electron–hole pair separation. On the other hand, ZnO NR c‐axis length has a dominant effect in visible light resulting from a multiphoton absorption mechanism due to light reflection and trapping behavior in the free space between adjacent ZnO NRs. Furthermore, oxygen vacancies and defects in ZnO NRs are associated with the broad visible emission band of different energy levels also highlighting the possibility of the multiphoton absorption mechanism. It is demonstrated that the minimum average of ZnO NR c‐axis length must satisfy the linear regression model of Z p,min = 6.31d to initiate the multiphoton absorption mechanism under visible light. This work indicates the broadening of absorption spectrum from UV to visible light region by incorporating a controllable diameter and c‐axis length on vertically aligned ZnO NRs, which is important in optimizing the design and functionality of electronic devices based on light absorption mechanism. 相似文献
87.
Peng Luo Weixing Yao Piao Li 《Fatigue & Fracture of Engineering Materials & Structures》2019,42(4):854-870
An approach based on the local stress response is proposed to locate the fatigue critical point for metallic blunt notched specimens under multiaxial fatigue loading. According to the stress analysis, both stress gradient and gradient of loading nonproportionality exist at notch root. The plane in the vicinity of the notch that passes through the fatigue critical point and experiences the maximum shear stress amplitude is defined as the critical plane for notch specimens (CPN). Furthermore, the Susmel's fatigue damage parameter is modified to assess fatigue life of notched components by combining CPN and the theory of critical distance (TCD). The multiaxial fatigue test of the thin‐walled round tube specimens made of Ni‐base alloy GH4169 is carried out to verify the above approaches. In addition, test data of two kinds of materials are collected. The results show that the maximum absolute error of the fatigue critical point is 9.6° and the majority of the predicted life falls within the three‐time scatter band. 相似文献
88.
Xin Yang Haoran Wang Shaozhe Chen Xinglin Piao Dongsheng Zhou Qiang Zhang Baocai Yin Xiaopeng Wei 《Computer Animation and Virtual Worlds》2019,30(3-4)
Scene understanding is essential to robotic navigation and autonomous driving as it provides semantic information to their controlling system. However, it will fail when processing low‐light images/videos captured under adverse weather or at night use state‐of‐the‐art scene understanding methods. A naive way to directly infer semantics from low‐light images is ill posed because the low‐light condition distorts pixel intensities and buries details. In order to address this problem, we propose the Deep Intensity Manipulation Network (DIMNet), which could relight the input images and recover the details, and combine the DIMNet with a scene understanding network to get a cascaded network to learn the semantics from low‐light images. Through learning pixel intensity manipulation, our method can generate images not only visually pleasing but also practical for scene understanding. Qualitative and quantitative experiments demonstrate that the proposed method is effective and robust for both synthetic and real‐world images. 相似文献
89.
Printed electronics is a rapidly expanding research field because of its incomparable economic efficiency. While various types of inks are employed in the printing of electronics, metal–organic decomposition (MOD) ink is an interesting type of ink worth paying attention to. MOD ink consists of metals in their ionic state and the advantages include simple preparation, long shelf life, high jetting stability, and low temperature processing. Additionally, the ease of large‐scale fabrication through industrial scale printing processes makes MOD ink ideal for printed electronics. To improve the conductivity, morphology, and variety of the conductive substance resulting from MOD ink, recent research has focused on the variation of the ink composition, printing techniques, and sintering methods. Here, the conventional methods of preparation and processing of MOD ink are introduced, followed by discussion of various research efforts to date. Furthermore, applications and their examples including but not limited to conventional conductive patterning are presented. 相似文献
90.
2007年7月9～12日,ISO/TC44第28届全体会议及有关分技术委员会（SC3,SC7）会议在法国巴黎召开。笔者以中国代表的身份参加了这些会议,会议的有关情况报告如下。 相似文献