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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第9期11卷 673-680页

作者： Bin CHEN Sheng-xiang xiao peng-cheng GU Xiang-jin LIN Department of Orthopaedics the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective：In order to achieve accurate implantation of the acetabular prosthesis in total hip arthroplasty（THA）,we designed individual templates based on a three-dimensional（3D） model generated from computed tomography（CT） ***：Individual templates were designed for 12 patients who underwent THA.A physical template was designed to conform to the contours of the patient＇s acetabulum and to confirm the rotation of the acetabular *** guided the acetabular component ***：The preoperative and postoperative X-ray and CT scans were obtained to assess the location with respect to the accuracy of the acetabular *** all patients,the abduction angle of the acetabular component was 46.7°to 54.3°and the anteversion angle was 11.3°to 18.5°Conclusions：The assessment of postoperative CT scans demonstrated higher accuracy of the acetabular component bore when used with the individual ***,the individual template can be an alternative to the computer-assisted navigation systems,with a good cost-performance ratio.

关键词： Total hip arthroplasty Templates Acetabular prosthesis

Evaluation of infrared camouflage effectiveness via a multi-fractal method

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Defence Technology（防务技术） 2021年第3期17卷 748-754页

作者： xiao-peng cheng Bo-wang Shu Ya-jing Chang Xin Li Da-bin Yu State Key Laboratory of Pulsed Power Laser Technology College of Electronic EngineeringNational University of Defense TechnologyHefei230037PR China

This paper reports an alternative approach to the evaluation of infrared camouflage effectiveness via a multi-fractal method. By calculating multi-fractal spectra of the target region and the background regions in an infrared image, the spectrum shape features and the discrete Frechet distances among these spectra were used to analyze the camouflage effectiveness of the target qualitatively and quantitatively,and the correlation coefficients of the spectra were further used as the index of camouflage *** was found that the camouflaged target had better camouflage effectiveness than the target without camouflage in the same one background, and the same one camouflaged target had different camouflage effectiveness in different backgrounds. On the whole, the target matching well with its background had high camouflage effectiveness value. This approach can expand the application of multi-fractal theory in infrared camouflage technology, which should be useful for the research of infrared camouflage materials, the design of camouflage patterns as well as the deployment of military equipment in battlefield.

关键词： Infrared Camouflage effectiveness Multi-fractal Similarity

A low-complexity multiple signal representation scheme in downlink OFDM-CDMA

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Science in China(Series F) 2009年第12期52卷 2433-2444页

作者： DAN LiLin xiao Yue cheng peng WU Gang LI ShaoQian National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of China Chengdu 610054 China

OFDM-CDMA is an attractive technique for broadband wireless communication. However, the high peakto-average power ratio （PAPR） of the downlink signals, generated from multiple spread codes, remains a serious problem. In this paper, a low-complexity multiple signal representation （MSR） scheme is proposed to control the PAPR problem in downlink OFDM-CDMA systems. The proposed scheme generates multiple candidate signals by a novel user grouping scheme, which is without distortion and can provide more PAPR reduction than the conventional MSR schemes, such as partial transmit sequence （PTS） and selective mapping （SLM）. Furthermore, a low-complexity processing structure is developed using a novel joint spreading and inverse fast Fourier transform （S-IFFT） to simplify the generation of multiple candidate signals. Complexity analysis and numerical results show that the OFDM-CDMA systems employing the proposed scheme have better tradeoff between PAPR reduction and computational complexity, compared with the conventional MSR schemes.

关键词： OFDM-CDMA spread-IFFT (S-IFFT) multiple signal representation (MSR) user grouping

Analysis of destructive effect of Zn on carbon brick and way of Zn into carbon brick

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Journal of Iron and Steel Research International 2024年第6期31卷 1344-1354页

作者： peng-bo Liu Shu-sen cheng Yu-qing Xue xiao-man cheng Zhao Liu University of Science and Technology Beijing Beijing 100083China Ministry of Ironmaking Shangdong Taishan Steel Group Co.Ltd.Taian 271000ShandongChina

The service life of a blast furnace depends largely on the degree of damage to the carbon brick in the *** brick and ramming material in the hearth of a 1780 m3 blast furnace after shutdown were sampled and *** was found that the substances in the cracks of the carbon brick near and above the taphole were ZnO and Zn_(2)SiO_(4),whereas the substances in the cracks of the carbon brick below the taphole were *** reaction of Zn with CO,SiO_(2),and Fes generates ZnO,Zn_(2)SiO_(4),and ZnS,resulting in volume expansion,which is an important reason for the cracking of carbon ***,several obvious Zn vapor flow channels were found in the ramming material,through which Zn vapor could enter the carbon brick,causing damage to the carbon *** the compactness of the ramming material is beneficial to preventing Zn vapor from entering the carbon brick through the voids in the ramming material,reducing the destructive effect of Zn on the carbon brick and further extending the service life of the blast furnace.

关键词： Zn Blast furnace Carbon brick Ramming material Crack

Metochalcone induces senescence-associated secretory phenotype via JAK2/STAT3 pathway in breast cancer

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Oncology Research 2024年第5期32卷 943-953页

作者： JIANBO ZHOU FENG WAN BIN xiao XIN LI cheng peng FU peng Department of Pharmacology West China School of PharmacySichuan UniversityChengduChina State Key Laboratory of Southwestern Chinese Medicine Resources Chengdu University of Traditional Chinese MedicineChengduChina Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologySichuan UniversityChengduChina chengdu No.1 Pharmaceutical Co. Ltd.PengzhouChina chengdu Push Bio-Technology Co. Ltd.ChengduChina

Breast and lung cancers are the leading causes of mortality and most frequently diagnosed cancers in women and men,respectively,*** the antitumor activity of chalcones has been extensively studied,the molecular mechanisms of isoliquiritigenin analog 2',4',4-trihydroxychalcone(metochalcone;TEC)against carcinomas remain less well *** this study,we found that TEC inhibited cell proliferation of breast cancer BT549 cells and lung cancer A549 cells in a concentration-dependent *** induced cell cycle arrest in the S-phase,cell migration inhibition in vitro,and reduced tumor growth in ***,transcriptomic analysis revealed that TEC modulated the activity of the JAK2/STAT3 and P53 *** triggered the senescence-associated secretory phenotype(SASP)by repressing the JAK2/STAT3 *** mechanism of metochalcone against breast cancer depended on the induction of SASP via deactivation of the JAK2/STAT3 pathway,highlighting the potential of chalcone in senescence-inducing therapy against carcinomas.

关键词： Metochalcone Breast cancer Lung cancer SASP JAK2/STAT3

Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum Science 2024年第1期21卷 641-653页

作者： Yun-peng He Hai-Bo cheng peng Zeng Chuan-Zhi Zang Qing-Wei Dong Guang-Xi Wan xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of Chinese Academy of Sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well *** learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis ***,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational ***,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different ***,there is heterogeneity in field data,which can dramatically impair the diagnostic *** solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this ***,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC ***,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data ***,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the *** on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational *** the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

A Fluorine-Functionalized 3D Covalent Organic Framework with Entangled 2D Layers

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Chinese Journal of Polymer Science 2024年第8期42卷 1210-1216页

作者： Li-Bang xiao Zi-Han Wu Jun-Jie Xin Yuan-peng cheng Bo Gui Jun-Liang Sun cheng Wang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China College of Chemistry and Molecular Engineering Beijing National Laboratory for Molecular SciencesPeking UniversityBeijing 100871China

Constructing three dimensional(3D)covalent organic frameworks(COFs)through the entanglement of two dimensional(2D)nets is a promising but underdeveloped ***,we report the design and synthesis of a fluorine functionalized 3DCOF(3D-An-COF-F)formed by entangled 2D sql *** structure of 3D-An-COF-F was determined by the combination of continuous rotation electron diffraction technique and modelling based on the chemical information from real ***,compared to the isostructural 3D-An-COF without F atom s,3DAn-COF-F showed an improved CO_(2)sorption ability and higher CO_(2)/N_(2)*** study not only demonstrated the generality of constructing 3D COFs with entangled 2D nets by introducing bulky groups vertically in planar building blocks,but also will expand the diversity of 3D COFs for various applications.

关键词： 3D covalent organic frameworks Fluorine Entangled 2D layers Electron diffraction CO_(2)adsorption

Stability analysis of intermittently jointed rock slopes based on the stepped failure mode

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Journal of Mountain Science 2024年第3期21卷 1019-1035页

作者： LI Dejian FU Junwen LI Hekai cheng xiao ZHAO Lianheng ZHANG Yingbin peng Xinyan School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Institute for Disaster Management and Reconstruction College of Architecture&EnvironmentSichuan UniversityChengdu 610065China School of Civil Engineering Key Laboratory of Heavy-Haul Railway Engineering StructureMinistry of EducationHunan Provincial Key Laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering StructureCentral South UniversityChangsha 410075China

In practical engineering,due to the noncontinuity characteristics of joints in rock slopes,in addition to plane failure,stepped sliding failure may occur for intermittently jointed rock *** for intermittently bedding jointed rock slopes,the correlation and difference in strength parameters between joints and rock bridges,along with the various failure modes and intermittency of rock bridges,contribute to the complexity of stepped failure modes and the unpredictability of failure *** on the upper-bound limit analysis method and multi-sliders step-path failure mode,considering the shear and tensile failure of rock bridges and the weakened relationship between the strength parameters of rock bridges and jointed surfaces,by introducing the modified M-C failure criterion and the formula for calculating the energy consumption of tensile failure of rock bridges,two failure mechanisms are constructed to obtain the safety factor(F_(s))of intermittently jointed rock *** sequential quadratic programming method is used to obtain the optimal upper-bound solution for F_(s).The influence of multiple key parameters(slope height H,horizontal distance L,Slope angleβ,shear strength parameters of the rock bridgeφr and cr,Dimensionless parameter u,weakening coefficients of the internal friction angle and cohesion between the rock bridges and joint surfaces Kφand Kc)on the stability analysis of intermittently jointed rock slopes under the shear failure mode of rock bridges as well as under the tensile failure mode is also *** reliability of the failure mechanisms is verified by comparative analysis with theoretical results,numerical results,and landslide cases,and the variation rules of F_(s)with each key parameter are *** results show that F_(s) varies linearly withφr and cr of the rock bridge and with K_(φ)and K_(c),whereas F_(s)changes nonlinearly with H and *** particular,with the increase in Kφand Kc,Fs increases by approximately 52.

关键词： Jointed rock slopes Stepped sliding failure Weakening characteristics Modified M‒C failure criterion

Unsupervised construction of health indicator for rotating machinery via multi-criterion feature selection and attentive variational autoencoder

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Science China(Technological Sciences) 2024年第5期67卷 1524-1537页

作者： LI XinYu cheng ChangMing peng ZhiKe State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai200240China School of Mechanical Engineering Ningxia UniversityYinchuan750021China

Health indicator(HI)construction is a crucial task in degradation evaluation and facilitates the prognostic and health management(PHM)of rotating *** interference from artificial labeling,the HI construction approaches in an unsupervised manner have attracted substantial ***,current unsupervised methods generally struggle with two problems:(1)ignorance of both redundancy between features and global variability of features during the feature selection process;(2)inadequate utilization of information from different sampling *** tackle these problems,this work develops a novel unsupervised approach for HI construction that integrates multi-criterion feature selection and the Attentive Variational Autoencoder(Attentive VAE).Explicitly,a multi-criterion feature selection(Mc FS)algorithm together with an elaborately designed metric is proposed to determine a superior feature subset,considering the relevance,the redundancy,and the global variability of features ***,for the adequate utilization of the information from distinct sampling moments,a deep learning model named Attentive VAE is *** Attentive VAE is solely fed with the selected features in the health state for model training and the HI is derived through the reconstruction error to reveal the degradation degree of *** case studies based on genuine experimental datasets are involved to quantitatively evaluate the superiority of the developed approach,demonstrating its superiority over other unsupervised methods for characterizing degradation *** effectiveness of both the Mc FS algorithm and the Attentive VAE is verified by ablation experiments,respectively.

关键词： health indicator(HI) unsupervised learning multi-criterion feature selection global variability attention mechanism

Matrix metalloproteinase 2 degrades collagen I to regulate ovarian development by association with an insulin-like peptide

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Insect Science 2024年第4期31卷 1090-1106页

作者： Yi Wei xiao-Lin Zhou peng Chen Tai-Hang Liu cheng Lu Min-Hui Pan State Key Laboratory of Silkworm Genome Biology Southwest UniversityChongqingChina Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry Southwest UniversityChongqingChina Wenzhou Institute University of Chinese Academy of SciencesWenzhouZhejiang ProvinceChina

The ovary generally undergoes tissue remodeling during larval to pupal transition,which includes membrane degeneration and ovariole *** the same time,the hormones produced by insects significantly change during ***,the regulatory mechanism for ovarian development and hormones is not fully understood in ***,we found that matrix metalloproteinase 2(MMP2)was highly expressed in the ovarian capsules and ovarioles,and the development was abnormal after knocking out MMP2 in Bombyx *** process of abnormal degradation of collagen I due to MMP2 deletion,which resulted in abnormal development of ovarioles and eggs,was analyzed in *** proteomics of ovaries in the MMP2-knock out and wild type strains showed a critically significant difference in the expression of a protein,insulin-like peptide(ILP).Additional analysis revealed significant alteration of ILP during ovarian development,and abnormal expression of ILP significantly affected ovarian development in vivo and MMP2 expression in vitro and in *** results showed that MMP2 regulation of ovarian tissue remodeling is closely related to ILP *** study provides new insights into the regulatory mechanism of MMP2 and ovarian development in ***.

关键词： Bombyx mori collagen I insulin-like peptide matrix metalloproteinase ovarian development