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Key machining characteristics in ultrasonic vibration cutting of single crystal silicon for micro grooves

Advances in Manufacturing 2019年第3期7卷 303-314页

作者： Jun-Yun Chen Tian-Ye jin xi-Chun Luo College of Vehicles and Energy Yanshan UniversityQinhuangdao 066004HebeiPeople's Republic of China Department of Design Manufacture and Engineering ManagementFaculty of EngineeringUniversity of StrathclydeGlasgow G11XJUK Center for Precision Engineering Harbin Institute of TechnologyHarbin 150001People's Republic of China

Structured complex silicon components have been widely used in solar cells,biomedical engineering and other industrial *** silicon is a typical brittle material,ultrasonic vibration cutting(UVC)is a promising method to achieve better cutting performance than conventional ***-frequency ID UVC possesses higher nominal cutting speed and material removal rate than many 2D/3D UVC systems,and thus,it has great development potential in industrial applications of structured silicon ***,few researchers have applied ID UVC to the cutting of structured silicon surfaces,since its main drawback is tool marks imprinted by the vibration on machined *** this study,to uncover the key machining characteristics under the condition of ID UVC,a series of tests involving diamond cutting grooves were first performed on the silicon *** machined surface and chips were subsequently measured and analyzed to evaluate the critical undeformed chip thickness,surface characteristics,and chip *** the main drawback of ID UVC,a novel theoretical model was developed for predicting the length of tool marks and evaluating the impact of tool marks on the surface *** results demonstrated that the critical undeformed chip thickness of silicon reached 1030 nm under a certain vibration amplitude and that an array of micro grooves was generated at the plastic region with a surface roughness(7?a)as low as 1.11 ***,the micro topography of the continuous chips exhibited discontinuous clusters of lines with diameters of dozens of nanometers,only composed of *** novel theoretical model was able to predict the length of tool marks with low ***,the impact of tool marks on the surface finish can be reduced and even eliminated with help of the model.

关键词： Ultrasonic vibration cutting(UVC) Single crystal Silicon Micro groove Chip Tool vibration mark

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Multi-Task Learning for Food Identification and Analysis with Deep Convolutional Neural Networks

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Journal of Computer Science & Technology 2016年第3期31卷 489-500页

作者： xi-jin Zhang Yi-Fan Lu Song-Hai Zhang Department of Computer Science and Technology Tsinghua University Beijing 100084 China

In this paper, we proposed a multi-task system that can identify dish types, food ingredients, and cooking methods from food images with deep convolutional neural networks. We built up a dataset of 360 classes of different foods with at least 500 images for each class. To reduce the noises of the data, which was collected from the Internet, outlier images were detected and eliminated through a one-class SVM trained with deep convolutional features. We simultaneously trained a dish identifier, a cooking method recognizer, and a multi-label ingredient detector. They share a few low-level layers in the deep network architecture. The proposed framework shows higher accuracy than traditional method with handcrafted features, and the cooking method recognizer and ingredient detector can be applied to dishes which are not included in the training dataset to provide reference information for users.

关键词： multi-task learning convolutional neural network food recognition machine learning

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Direct numerical simulation of turbulent boundary layer over an anisotropic compliant wall

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Acta Mechanica Sinica 2019年第2期35卷 384-400页

作者： Qian-jin xia Wei-xi Huang Chun-xiao Xu AML Department of Engineering MechanicsTsinghua University Beijing 100084 China

Direct numerical simulation of a spatially developing turbulent boundary layer over a compliant wall with anisotropic wall material properties is performed. The Reynolds number varies from 300 to approximately 860 along the streamwise direction, based on the external flow velocity and the momentum thickness. Eight typical cases are selected for numerical investigation under the guidance of the monoharmonic analysis. The instantaneous flow fields exhibit the traveling wavy motion of the compliant wall, and the frequency-wavenumber power spectrum of wall pressure fluctuation is computed to quantify the mutual influence of the wall compliance and the turbulent flow at different wave numbers. It is shown that the Reynolds shear stress and the pressure fluctuation are generally enhanced by the wall compliance with the parameters considered in the present study. A dynamical decomposition of the skin-friction coefficient is derived, and a new term (CW) appears due to the wall-induced Reynolds shear stress. The influence of the anisotropic compliant wall motion on the turbulent boundary layer through the wall-induced negative Reynolds shear stress is discussed. To elucidate the underlying mechanism, the budget analysis of the Reynolds stresses transportation is further carried out. The impact of the wall compliance on the turbulent flow is disclosed by examining the variations of the diffusion and velocity-pressure correlation terms. It is shown that increase of the Reynolds stresses inside the flow domain is caused by enhancement of the velocity-pressure correlation term, possibly through the long-range influence of the wall compliance on the pressure field, rather than diffusion of the wall-induced Reynolds shear stress into the fluid flow.

关键词： Turbulent boundary layer Anisotropic compliant wall Direct numerical simulation Skin-friction coefficient Reynolds shear stress

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Spatial Pattern of Long-term Residence in the Urban Floating Population of China and its Influencing Factors

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Chinese Geographical Science 2021年第2期31卷 342-358页

作者： CHEN Le xi Meijun jin Wanfu HU Ya School of Tourism&Research Institute of Human Geography Xi’an International Studies UniversityXi’an 710128China School of Economics Xi’an University of Finance and EconomicsXi’an 710100China School of Geography and Tourism Guangdong University of Finance and EconomicsGuangzhou 510320China

Exploring long-term residence among the urban floating population is crucial to understanding urban growth in China,particularly since the 2008 financial *** using China Migrants Dynamic Survey data for 2012–2014,China Labor-force Dynamics Survey data for 2014–2016,and macroscale urban matched data,we analyzed the spatial pattern of long-term residential behavior in China’s urban floating population in 2012–2016 and developed an urban spatial utility equilibrium model containing‘macro’urban factors and‘micro’individual and household factors to explain the *** results first revealed that long-term residence is defined as≥6 yr for the urban floating population in ***,members of this population are more likely to be long-term residents of the megacities in the three urban agglomerations in eastern China as well as of small and medium-sized cities in western and northeastern China,whereas short-term residence is more likely in cities in central China and near the three urban ***,urban population density and housing prices,both have a significant U-shaped effect,are main factors affecting the spatial pattern of long-term residence.

关键词： long-term residence urban floating population spatial pattern spatial utility equilibrium model China

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Evaluation of the performance of surface treatments on concrete durability

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第5期11卷 349-355页

作者： Yu-xi ZHAO Pan-feng DU Wei-liang jin Institute of Structural Engineering Zhejiang University Hangzhou 310027 China

This paper reports on a laboratory-based study carried out to evaluate the effectiveness of surface treatments on the durability of concrete and suggests a number of different evaluation methodologies for assessing the performance of various surface treatments. Durability of untreated and treated concrete specimens was evaluated by measuring chloride diffusion,charge passing capacity,air permeability and water absorption. A total of six concrete surface treatments were selected to represent different generic types,including coating,penetrant and mixed-use treatments. Results show that the concrete specimens with a coating procedure have a better long-term performance and effectiveness than the specimens with the penetrant treatments. This work also indicates that the wetting and drying cycles test can be used to assess the weatherability of the surface treatments. The ASTM C 1202 and the Autoclam air permeability test can be used to evaluate the effectiveness of surface treatments quantitatively. Further work is needed,however,to assess the longevity of the various surface treatments.

关键词： Surface treatment Concrete Durability Evaluation

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Small cell lung cancer with peripheral neuropathy as the first symptom:Two case reports

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World Journal of Clinical Cases 2025年第9期13卷 30-40页

作者： Man Luo xiao-xi Lu Dan-Yang Meng jin Hu Department of Neurology Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina Department of Information Technology Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina

BACKGROUND Small cell lung cancer(SCLC)is the most malignant type of lung *** in the latent period and early stage of the tumor,SCLC is prone to produce distant metastases with complex and diverse clinical *** is most closely related to paraneoplastic syndrome,and some cases present as paraneoplastic peripheral neuropathy(PPN).PPN in SCLC appears early,lacks specificity,and often occurs before diagnosis of the primary *** is easy to be misdiagnosed as a primary disease of the nervous system,leading to missed diagnosis and delayed diagnosis and *** SUMMARY This paper reports two cases of SCLC with limb weakness as the first *** first symptoms of one patient were rash,limb weakness,and abnormal *** patient was repeatedly referred to the hospital for limb weakness and rash for>1 year,during which time,treatment with hormones and immunosuppressants did not lead to significant improvement,and the condition gradually *** patient was later diagnosed with SCLC,and the dyskinesia did not worsen as the dermatomyositis improved after antineoplastic and hormone *** second case presented with limb numbness and weakness as the first symptom,but the patient did not pay attention to ***,the patient was diagnosed with SCLC after facial edema caused by tumor thrombus invading the ***,he was diagnosed with extensive SCLC and died 1 year after *** The two cases had PPN and abnormal electromyography,highlighting its correlation with early clinical indicators of SCLC.

关键词： Paraneoplastic peripheral neuropathy Small cell lung cancer Peripheral neuropathy Electromyography Dermatomyositis Case report

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Semi-Implantable Bioelectronics

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Nano-Micro Letters 2022年第7期14卷 354-408页

作者： Jiaru Fang Shuang Huang Fanmao Liu gen He xiangling Li xinshuo Huang Hui-jiuan Chen xi xie State Key Laboratory of Optoelectronic Materials and Technologies Guangdong Province Key Laboratory of Display Material and TechnologySchool of Electronics and Information TechnologySun Yat-Sen UniversityGuangzhou 510006People’s Republic of China

Developing techniques to effectively and real-time monitor and regulate the interior environment of biological objects is significantly important for many biomedical engineering and scientific applications, including drug delivery, electrophysiological recording and regulation of intracellular activities. Semi-implantable bioelectronics is currently a hot spot in biomedical engineering research area, because it not only meets the increasing technical demands for precise detection or regulation of biological activities, but also provides a desirable platform for externally incorporating complex functionalities and electronic integration. Although there is less definition and summary to distinguish it from the well-reviewed non-invasive bioelectronics and fully implantable bioelectronics, semi-implantable bioelectronics have emerged as highly unique technology to boost the development of biochips and smart wearable device. Here, we reviewed the recent progress in this field and raised the concept of “Semi-implantable bioelectronics”, summarizing the principle and strategies of semi-implantable device for cell applications and in vivo applications, discussing the typical methodologies to access to intracellular environment or in vivo environment, biosafety aspects and typical applications. This review is meaningful for understanding in-depth the design principles, materials fabrication techniques, device integration processes, cell/tissue penetration methodologies, biosafety aspects, and applications strategies that are essential to the development of future minimally invasive bioelectronics.

关键词： Semi-implantable bioelectronics Cell applications In vivo applications

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Stock Efficiency Evaluation Based on Multiple Risk Measures:A DEA-Like Envelopment Approach

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Journal of Systems Science & Complexity 2022年第4期35卷 1480-1499页

作者： LI Jun GAO Hengxuan LI Yongjun jin xi LIANG Liang School of Management University of Science and Technology of ChinaHefei230026China School of Management Hefei University of TechnologyHefei230009China

This paper proposes a new approach for stock efficiency evaluation based on multiple risk measures. A derived programming model with quadratic constraints is developed based on the envelopment form of data envelopment analysis(DEA). The derived model serves as an input-oriented DEA model by minimizing inputs such as multiple risk measures. In addition, the Russell input measure is introduced and the corresponding efficiency results are evaluated. The findings show that stock efficiency evaluation under the new framework is also effective. The efficiency values indicate that the portfolio frontier under the new framework is more externally enveloped than the DEA efficient surface under the standard DEA framework.

关键词： Data envelopment analysis(DEA) multiple risk measures portfolio selection stock efficiency evaluation

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Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

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Optoelectronics Letters 2008年第4期4卷 302-306页

作者： BAO jin LIANG xi-xia Departement of Physics Inner Mongolia University Hohhot 010021 China

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, Gaxin1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.

关键词：三元混合晶体声子极化声子成分研究

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Analysis of level structure and monopole effects in Ca isotopes

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Nuclear Science and Techniques 2024年第10期35卷 161-167页

作者： jin Li Ai-xi Chen Amir Jalili Han-Kui Wang School of Science Zhejiang Sci-Tech UniversityHangzhou 310018China

Understanding the properties of nuclei near the double magic nucleus^(40)Ca is crucial for both nuclear theory and *** this study,Ca isotopes were investigated using an extended pairing-plus-quadrupole model with monopole *** negative-parity states of^(44)Ca were coupled with the intruder orbital g_(9/2)at 4 *** values of E_(4+)/E_(2+)agree well with experimental trend from^(42)Ca to^(50)Ca,considering monopole effects between νf_(7/2)and νp_(3/2)(νf_(5/2)).This monopole effect,determined from data of^(48)Ca and^(50)Ca,supports the proposed new nuclear magic number N=34 by predicting a high-energy 2^(+)state in^(54)Ca.

关键词： Shell model Doubly magic Isotopes Monopole effects Level structure

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