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Acta Mechanica Sinica 2011年第5期27卷 785-795页

作者： Chun-Chuan liu Feng-Ming li Ting-wei liang Wen-Hu Huang P. O. Box 137 School of AstronauticsHarbin Institute of Technology150001 Harbin China

In this paper,wave and vibratory power transmission in a finite L-shaped Mindlin plate with two simply supported opposite edges are investigated using the wave *** dynamic responses,active and reactive power flow in the finite plate are calculated by the Mindlin plate theory （MPT） and classic plate theory （CPT）.To satisfy the boundary conditions and continuous conditions at the coupled junction of the finite L-shaped plate,the near-field and far-field waves are entirely contained in the wave *** in-plane longitudinal and shear waves are also *** results indicate that the vibratory power flow based on the MPT is different from that based on the CPT not only at high frequencies but also at low and medium *** influence of the plate thickness on the vibrational power flow is *** the results it is seen that the shear and rotary inertia correction of the MPT can influence the active and reactive power at the junction of the L-shaped plate not only at high frequencies but also at low and medium ***,the effects of structural damping on the active and reactive power flow at the junction are also analyzed.

关键词： Finite L-shaped Mindlin plate Active power flow Reactive power flow Wave approach

Modification and refinement effects of Sb and Sr on Mg_(17)Al_(12) and Mg_2Si phases in Mg-12Al-0.7Si alloy

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China Foundry 2016年第5期13卷 310-315页

作者： Zhi-wen Wang Hong-xia Wang Jia-lin Gong Ming li wei-li Cheng wei liang Key Laboratory of lnterface Science and Engineering in Advanced Materials Taiyuan University of Technology Ministry of Education Taiyuan 030024 Shanxi China

The effects of Sb and Sr on the modification and refinement of Mg17Al12 and Mg2Si phases in Mg- 12Al-0.7Si alloy were investigated and compared. The microstructure and mechanical properties of Mg-12Al0.7Si alloy and its modification mechanism by Sb and Sr were investigated using a scanning electron microscope （SEM）, an energy dispersive spectrometer （EDS）, X-ray diffraction （XRD） and differential thermal analysis （DTA）. The results indicate that by adding 0.5wt.% Sb to the Mg-12Al-0.7Si alloy, the Mg17Al12 phase was refined and broken into some discontinuous island structures. However, some network Mg17Al12 phases still can be detected in Mg-12Al-0.7Si-0.09Sr alloy. Therefore, Sb performs better in modification and refinement of Mg17Al12 phase than does Sr. Small amounts of fine polygonal shaped Mg2Si phases were found in Mg-12AI-0.7Si-0.5Sb alloy, while the morphology of Mg2Si phases in Mg-12Al-0.7Si-0.09Sr alloy changed from the coarse Chinese script shapes to fine granule and irregular polygonal shapes, indicating that the effects of modification and refinement on Mg2Si phase are more significant by adding 0.09wt.% Sr than 0.5wt.% Sb. The ultimate tensile strengths of the Sb and Sr modified Mg-12Al-0.7Si alloys were considerably increased both at room temperature and at 200 ℃.

关键词： magnesium alloy Sb Sr Mg17Al12 phase Mg2Si phase

Oxygen and hydrogen isotope exchange of geopressured thermal water in the central Guanzhong basin

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Mining Science and Technology 2009年第1期19卷 115-119页

作者： YU Juan MA Zhi-yuan WANG Zhao-wei li wei-liang SU Yan Environmental Science and Engineering Institute Chang ＇an University Xi＇an Shaanxi 710054 China Xi＇an Institute of Geology and Minerals Resources Xi＇an Shaanxi 710054 China Xi ＇an Institute of Thermal Power Research Xi＇an Shaanxi 710032 China

Geothermal water of Xi＇an and Xianyang in the central Guanzhong basin is typically geopressured thermal water in China. 5180 and 5D data of geopressured thermal water＇in Xi＇an and Xianyang, combined with data from the perimeter of the basin, are analyzed to study features of hydrogen and oxygen shifts. The results show that ^18O exchange of geothermal water at the perimeter of the basin and in the non-geopressured thermal water in the center of the basin is not evident, while in most of the geopressured thermal water in the central basin, in cities such as Xi＇an and Xianyang, significant oxygen exchange had taken place as well as hydrogen exchange, suggesting that isotope exchanges would slowly move the geothermal water system towards equilibrium. Thermal water reservoirs in the central basin have passed through significant water-rock reactions. Moreover, the geothermal reservoir of Xianyang city is relatively much more enclosed than that of Xi＇an city. It has been observed that the more enclosed the geological environment of geothermal water is, the more obvious the oxygen shifts are. With the increasing of the depth, residence time, total amounts of dissolute solids and temperatures of geothermal waters, the oxygen exchange accelerates.

关键词： Guanzhong basin geopressured thermal water.^18O shifts

Microwave-assisted Solventless Biginelli Reaction Catalyzed by Montmorillonite Clay-SmCl_3 6H_2O System

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Chinese Chemical Letters 2003年第10期14卷 993-995页

作者： Yu Xia li, wei liang BAO Department of Chemistry, Zhejiang University, Xi Xi Campus, Hangzhou 310028 Department of Chemistry Zhejiang University Xi Xi Campus Hangzhou 310028 China

4-Aryl/alkyl-3,4-dihydro-2(1H)-pyrimidone esters and 5-acetyl-4-aryl/or alkyl-6-methyl- 3, 4-dihydropyrimidin-2(l)-ones were synthesised efficientiy using montmorillonite clay- SmCl3 6H2O system promoted by microwave ... 详细信息

关键词： Microwave samarium trichloride montmorillonite Biginelli reaction pynmidone.

Femtosecond Reflections of Bulk GaAs and GaAs/AlGaAs Multiple Quantum Wells

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Chinese Physics Letters 1996年第3期13卷 237-240页

作者： li wei-liang QIU Zhi-ren PENG Wen-ji HUANG Xu-guang ZHOU Jian-ying YU Zhen-xin State Key Laboratory of Ultrafast Laser Spectroscopy Zhongshan UniversityGuangzhou 510275

We present room temperature femtosecond rejection studies on the photocarrier dynamics of GaAs and GaAs/AlGaAs multiple quantum wells(MQW).A rising wing with a time constant of about.5 ps and an increased amplitude per carrier is observed for the MQW sample at carrier densities lower than 5×10^(11) cm^(-2).This phenomenon is explained as the saturation of the excitonic transitions.

关键词： GaAs/AlGaAs Femto Quantum

Lower Semicontinuity of the Solution Sets to Parametric Generalized Vector Equilibrium Problems

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Journal of Mathematical Research and Exposition 2011年第3期31卷 411-419页

作者： Jing Zhe li Hong wei liang Dan ZHAO College of Mathematics and Statistics Chongqing University Chongqing 401331 P. R. China

In this paper,by a scalarization method,the lower semicontinuity of the solution mappings to two kinds of parametric generalized vector equilibrium problems involving set-valued mappings is established under new assumptions which are weaker than the C-strict *** results extend the corresponding *** examples are given to illustrate our results.

关键词： parametric generalized vector equilibrium problems lower semicontinuity scalarization.

Domain generalization with semi-supervised learning for people-centric activity recognition

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Science China(Information Sciences) 2025年第1期68卷 171-188页

作者： Jing liU wei ZHU Di li Xing HU liang SONG Academy for Engineering & Technology Fudan University Shanghai East-bund Research Institute on Networking Systems of AI School of Optoelectronic Information and Computer Engineering University of Shanghai for Science & Technology

People-centric activity recognition is one of the most critical technologies in a wide range of real-world applications,including intelligent transportation systems, healthcare services, and brain-computer interfaces. Large-scale data collection and annotation make the application of machine learning algorithms prohibitively expensive when adapting to new tasks. One way of circumventing this limitation is to train the model in a semi-supervised learning manner that utilizes a percentage of unlabeled data to reduce the labeling burden in prediction tasks. Despite their appeal, these models often assume that labeled and unlabeled data come from similar distributions, which leads to the domain shift problem caused by the presence of distribution gaps. To address these limitations, we propose herein a novel method for people-centric activity recognition,called domain generalization with semi-supervised learning(DGSSL), that effectively enhances the representation learning and domain alignment capabilities of a model. We first design a new autoregressive discriminator for adversarial training between unlabeled and labeled source domains, extracting domain-specific features to reduce the distribution gaps. Second, we introduce two reconstruction tasks to capture the task-specific features to avoid losing information related to representation learning while maintaining task-specific consistency. Finally, benefiting from the collaborative optimization of these two tasks, the model can accurately predict both the domain and category labels of the source domains for the classification task. We conduct extensive experiments on three real-world sensing datasets. The experimental results show that DGSSL surpasses the three state-of-the-art methods with better performance and generalization.

关键词： activity recognition deep learning domain generalization semi-supervised learning adversarial training

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Combination of acoustic radiation force impulse imaging, serological indexes and contrast-enhanced ultrasound for diagnosis of liver lesions

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World Journal of Gastroenterology 2017年第30期23卷 5602-5609页

作者： Xiao-Lan Sun Hui Yao Qiong Men Ke-Zhu Hou Zhen Chen Chang-Qing Xu li-wei liang Department of Ultrasound Shanghai Yangpu District East Hospital Department of Radiotherapy Shanghai Yangpu District East Hospital Department of Oncology Shanghai Yangpu District East Hospital Department of Surgery Shanghai Yangpu District East Hospital Department of Pathology Shanghai Yangpu District East Hospital Department of Radiography Shanghai Yangpu District East Hospital Department of Gastroenterology Shanghai Yangpu District East Hospital

AIM To assess the value of combined acoustic radiation force impulse(ARFI) imaging, serological indexes and contrast-enhanced ultrasound(CEUS) in distinguishing between benign and malignant liver lesions. METHODS Patients with liver lesions treated at our hospital were included in this study. The lesions were divided into either a malignant tumor group or a benign tumor group according to pathological or radiological findings. ARFI quantitative detection, serological testing and CEUS quantitative detection were performed and compared. A comparative analysis of the measured indexes was performed between these groups. Receiver operating characteristic(ROC) curves were constructed to compare the diagnostic accuracy of ARFI imaging, serological indexes and CEUS, alone or in different combinations, in identifying benign and malignant liver lesions. RESULTS A total of 112 liver lesions in 43 patients were included, of which 78 were malignant and 34 were benign. Shear wave velocity(SWV) value, serum alpha-fetoprotein(AFP) content and enhancement rate were significantly higher in the malignant tumor group than in the benign tumor group(2.39 ± 1.20 m/s vs 1.50 ± 0.49 m/s, 18.02 ± 5.01 ng/m L vs 15.96 ± 4.33 ng/m L, 2.14 ± 0.21 d B/s vs 2.01 ± 0.31 d B/s; P lignant live

关键词： Combined diagnosis liver lesions Benign Malignant Differentiation

liver reserve function assessment by acoustic radiation force impulse imaging

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World Journal of Gastroenterology 2015年第32期21卷 9648-9655页

作者： Xiao-Lan Sun li-wei liang Hui Cao Qiong Men Ke-Zhu Hou Zhen Chen Ya-E Zhao Department of Ultrasound in Medicine Shanghai Shidong Hospital Department of Gastroenterology Shanghai Shidong Hospital Department of Ultrasound in Medicine Shanghai Second Military Medical University Affiliated Changhai Hospital Department of Oncology Shanghai Shidong Hospital Department of Surgery Shanghai Shidong Hospital Department of Pathology Shanghai Shidong Hospital Department of Radiology Shanghai Shidong Hospital

AIM: To evaluate the utility of liver reserve function by acoustic radiation force impulse(ARFI) imaging in patients with liver tumors. METHODS: Seventy-six patients with liver tumors were enrolled in this study. Serum biochemical indexes, such as aminotransferase(ALT), aspartate aminotransferase(AST), serum albumin(ALB), total bilirubin(T-Bil), and other indicators were observed. liver stiffness(LS) was measured by ARFI imaging, measurements were repeated 10 times, and the average value of the results was taken as the final LS value. Indocyanine green(ICG) retention was performed, and ICG-K and ICG-R15 were recorded. Child-Pugh(CP) scores were carried out based on patient's preoperative biochemical tests and physical condition. Correlations among CP scores,ICG-R15, ICG-K and LS values were observed and analyzed using either the Pearson correlation coefficient or the Spearman rank correlation coefficient. KruskalWallis test was used to compare LS values of CP scores, and the receiver-operator characteristic(ROC) curve was used to analyze liver reserve function assessment accuracy. RESULTS: LS in the ICG-R15 10%-20% group was significantly higher than in the ICG-R15 20% group was significantly higher than in the ICG-R15 < 10% group; and the difference was statistically significant(2.92 ± 0.29 vs 1.59 ± 0.32, P < 0.01). The LS value in patients with CP class A was lower than in patients with CP class B(1.57 ± 0.34 vs 1.86 ± 0.27, P < 0.05), while the LS value in patients with CP class B was lower than in patients with CP class C(1.86 ± 0.27 vs 2.47 ± 0.33, P < 0.01). LS was positively correlated with ICG-R15(r = 0.617, P < 0.01) and CP score(r = 0.772, P < 0.01). Meanwhile, LS was negatively correlated with ICG-K(r =-0.673, P < 0.01). AST, ALT and T-Bil were positively correlated with LS, while ALB was negatively correlated with LS(P < 0.05). The RO

关键词： Acoustic radiation force impulse liver reserve fun

Going To School With Mother On My Back

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Women of China 2000年第5期 24-25页

作者： li QIANG wei liang

Whether a family is happy or not depends much on the way one looks at life. What kind of family is in this article, happy or unhappy? You are sure to get your answer after reading the story of li Qiang, a first year s... 详细信息

关键词： School Going To School With Mother On My Back