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A Method with Parameter for Solving the Spectral Radius of Nonnegative Tensor

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Journal of the Operations Research Society of China 2017年第1期5卷 3-25页

作者： yi-yong li Qing-Zhi Yang Xi He School of Mathematical Sciences and Lab of Pure Mathematics and Combinatic Nankai UniversityTianjin 300071China

In this paper,a method with parameter is proposed for finding the spectral radius of weakly irreducible nonnegative *** is more,we prove this method has an explicit linear convergence rate for indirectly positive ***,the algorithm is exactly the NQZ method(proposed by Ng,Qi and Zhou in Finding the largest eigenvalue of a non-negative tensor SIAM J Matrix Anal Appl 31:1090–1099,2009)by taking a specific ***,we give a modified NQZ method,which has an explicit linear convergence rate for nonnegative tensors and has an error bound for nonnegative tensors with a positive Perron ***,we promote an inexact power-type ***,some numerical results are reported.

关键词： Nonnegative tensor Indirectly positive tensors linear convergence Perturbation Complexity

Novel AC Servo Rotating and linear Composite Driving Device for Plastic Forming Equipment

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 843-853页

作者： Jin-Tao liang Sheng-Dun Zhao yong-yi li Mu-Zhi Zhu School of Mechanical Engineering Xi'an Jiaotong UniversityXi'an 710049China School of Mechano-electronic Engineering Xidian UniversityXi'an 710071China Beijing Institute of Space Launch Technology Beijing 100076China

The existing plastic forming equipment are mostly driven by traditional AC motors with long trans- mission chains, low efficiency, large size, low precision and poor dynamic response are the common disadvantages. In order to realize high performance forming processes, the driving device should be improved, especially for com- plicated processing motions. Based on electric servo direct drive technology, a novel AC servo rotating and linear composite driving device is proposed, which features implementing both spindle rotation and feed motion with- out transmission, so that compact structure and precise control can be achieved. Flux switching topology is employed in the rotating drive component for strong robustness, and fractional slot is employed in the linear direct drive component for large force capability. Then the mechanical structure for compositing rotation and linear motion is designed. A device prototype is manufactured, machining of each component and the whole assembly are presented respectively. Commercial servo amplifiers are utilized to construct the control system of the proposed device. To validate the effectiveness of the proposed composite driving device, experimental study on thedynamic test benches are conducted. The results indicate that the output torque can attain to 420 N-m and the dynamic tracking errors are less than about 0.3 rad in the rotating drive, the dynamic tracking errors are less than about 1.6 mm in the linear feed. The proposed research provides a method to construct high efficiency and accu- racy direct driving device in plastic forming equipment.

关键词： Plastic forming Direct drive - Permanentmagnet motor linear feeding Servo control

Comparative study of different machine learning models in landslide susceptibility assessment: A case study of Conghua District, Guangzhou, China

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China Geology 2024年第1期7卷 104-115页

作者： Ao Zhang Xin-wen Zhao Xing-yuezi Zhao Xiao-zhan Zheng Min Zeng Xuan Huang Pan Wu Tuo Jiang Shi-chang Wang Jun He yi-yong li Wuhan Center China Geological SurveyMinistry of Natural Resources(Geosciences Innovation Center of Central South China)Wuhan 430205China Guangzhou Institute of Geological Survey Guangzhou 510080China Hubei Transportation Planning Design Institute Co. LtdWuhan 430050China

Machine learning is currently one of the research hotspots in the field of landslide *** clarify and evaluate the differences in characteristics and prediction effects of different machine learning models,Conghua District,which is the most prone to landslide disasters in Guangzhou,was selected for landslide susceptibility *** evaluation factors were selected by using correlation analysis and variance expansion factor *** four machine learning methods namely Logistic Regression(LR),Random Forest(RF),Support Vector Machines(SVM),and Extreme Gradient Boosting(XGB),landslide models were *** analysis and evaluation of the model were conducted through statistical indices and receiver operating characteristic(ROC)*** results showed that LR,RF,SVM,and XGB models have good predictive performance for landslide susceptibility,with the area under curve(AUC)values of 0.752,0.965,0.996,and 0.998,*** model had the highest predictive ability,followed by RF model,SVM model,and LR *** frequency ratio(FR)accuracy of LR,RF,SVM,and XGB models was 0.775,0.842,0.759,and 0.822,*** and XGB models were superior to LR and SVM models,indicating that the integrated algorithm has better predictive ability than a single classification algorithm in regional landslide classification problems.

关键词： Landslides susceptibility assessment Machine learning Logistic Regression Random Forest Support Vector Machines XGBoost Assessment model Geological disaster investigation and prevention engineering

Gadolinium chloride and salvia miltiorrhiza compound ameliorate reperfusion injury in hepatocellular mitochondria

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World Journal of Gastroenterology 2003年第9期9卷 2040-2044页

作者： Wen-Hai Zhang Jin-Sheng Wang yong Zhou Jian-yi li Department of General Surgery,Second Affiliated Hospital,China Medical University,Shenyang 110022,liaoning Province,China Department of General Surgery Second Affiliated Hospital China Medical University 39 Huaxiang Road Tiexi District Shenyang 110022 Liaoning Province China. surgeonzwh@***

AIM: To investigate the effect of gadolinium chloride (GaCl3)and salvia miltiorrhiza compound (SMCo) on ischemia and reperfusion (I/R) injury in hepatocellular ***: Wistar rats were randomly to divided into control group, GaCl3 group, SMCo group and GaCl3 + SMCo group (n=15 each). GaCl3 (7 rmg@kg-1) was injected into tail vein on d 1 and d 2 in contrast group. SMCo ( 2 ml@kg-1) was injected into muscle on d 1 and d 2 in SMCo group. GaCl3+SMCo group received both GaCl3 (iv) and SMCo (im) injection. Control group received saline injection only. On d 3, all the rats were subjected to 2 h ischemia in the middle and left lobes of the liver, followed by reperfusion for 2 h, 6 h and 18 h respectively. The level of serum alanine aminotransferase (ALT) and malondialdehyde (MDA) in hepatocellular mitochondria was measured. Pathological changes in hepatic tissue and in hepatocellular mitochondria were determined with optical microscope and electronic microscope, ***: Remarkablly pathohistological and biochemical changes were detected after 6 h of I/R. Compared with control, the level of ALT was decreased in GaCl3, SMCo and GaCl3+SMCo treated groups (1 314.0±278.7 vs809.4±196.1,716.6±242.8 and 837.2±190.6 IU@L-1, respectively. P＜0.05).Similarly, the level of MDA was decreased in GaCl3, SMCo and GaCl3+SMCo treated groups (293.1±±51.1 vs 190.8±55.5,214.3±32.9 and 221.0±47.3 nmol@g-1, respectively, P＜0.05).Accordingly, in control group, swelling, degeneration, focal necrosis, infilt-ation of leucocyte were found in reperfused tissue under an optical microscope, and mitochondda swelling, rupture and even breakdown were seen under an electronic *** pathohistological and ultrastructural damages caused by I/R were greatly attenuated in GaCl3, SMCo and GaCl3+SMCo treated groups. However, there was no additive effect observed when GaCl3 and SMCo were used ***: Both GaCl3 and SMCo can alleviate the I/Rinjury in hepatocellular

关键词：氯化钆肝细胞线粒体损伤缺血再灌注损伤鼠尾草

Realization of BP and RBF Neural Networks and their Performance comparison

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Realization of BP and RBF Neural Networks and their Performa...

2006北京地区高校研究生学术交流会

作者： liu yong Zhang li-yi School of Information Engineering Tai Yuan University of Technology, Tai Yuan 030024 China

The paper introduces the basic theory of most popular ANN models---BP and RBF networks, demonstrates the learning procedure of each algorithm from mathematical angle, then it designs specific networks using MATLAB, and adopts them in function approaching. Finally, it elicits their property differences by comparing the simulation results.

关键词： Artificial neural network Back-Propagation Algorithm RBF network Training Approximation.

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从电子数据取证到电子数据侦查

计算机科学 2016年第B12期43卷 119-126页

作者：黄勇李毅郭恒汤伟盘石软件(上海)有限公司上海200333

从1999年美国出现第一款商用计算机取证工具并随后引入中国、2013年《刑事诉讼法》首次确立“电子数据”作为证据的法律地位至今，电子数据取证技术和产品已经在司法机关得到广泛应用。然而，电子数据取证以技术为先的理念极大地限制了... 详细信息

从1999年美国出现第一款商用计算机取证工具并随后引入中国、2013年《刑事诉讼法》首次确立“电子数据”作为证据的法律地位至今，电子数据取证技术和产品已经在司法机关得到广泛应用。然而，电子数据取证以技术为先的理念极大地限制了其自身发展的空间。电子数据侦查是跨越电子数据取证局限性的一种全新理念：在刑事案件侦查全过程中，以发现和收集案件相关证据、查明犯罪事实、确定和查获犯罪嫌疑人为目标，围绕以案件要素构成的研判模型，从海量电子数据中挖掘线索和证据，直至案件侦破终结的一系列案件研判活动。依此理念提出满足公安机关和检察机关侦查业务需求的解决方案，将为电子数据在刑事案件侦查领域的应用开辟更广阔的空间。

关键词：电子数据侦查案件构成要素案件研判模型智能研判

茶树油/海藻酸钠涂膜抑制鲜切苹果褐变的研究

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中国食品添加剂 2016年第12期27卷 164-168页

作者：刘永郑丽怡韦寿莲肇庆学院化学化工学院肇庆526061

以吸光度为优化指标和抑制鲜切苹果褐变为目标,在单因素的基础上采用响应面法进行优化抑制鲜切苹果褐变的茶树油/海藻酸钠涂膜最佳制备工艺条件,建立了海藻酸钠含量、甘油含量和茶树油含量对制备茶树油/海藻酸钠涂膜的数学模型。结果表... 详细信息

以吸光度为优化指标和抑制鲜切苹果褐变为目标,在单因素的基础上采用响应面法进行优化抑制鲜切苹果褐变的茶树油/海藻酸钠涂膜最佳制备工艺条件,建立了海藻酸钠含量、甘油含量和茶树油含量对制备茶树油/海藻酸钠涂膜的数学模型。结果表明:海藻酸钠含量和茶树油含量对吸光度的影响显著,甘油含量对吸光度的影响不显著,影响的大小顺序为茶树油含量>海藻酸钠含量>甘油含量;海藻酸钠含量与茶树油含量的交互作用对吸光度影响显著,海藻酸钠含量与甘油含量、甘油含量与茶树油含量的交互作用对吸光度的影响不显著;抑制鲜切苹果褐变的茶树油/海藻酸钠涂膜的最佳制备工艺为海藻酸钠含量1.30%、甘油含量1.99%和茶树油含量0.26%,此条件下吸光度的试验值为0.015。

关键词：茶树油海藻酸钠鲜切苹果

Magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility

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Nano-Micro Letters 2025年第2期17卷 401-416页

作者： Chen li Leilei liang Baoshan Zhang yi Yang Guangbin Ji School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration ***,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption *** top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass ***,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric *** theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ***,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of ***,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

关键词： Microwave absorption Radar-infrared compatible stealth Wrinkled MXene Magneto-dielectric synergy Multifunction

Rheological Phase Synthesis and Characterization of Copper Monosalicylate

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Wuhan University Journal of Natural Sciences 2003年第02A期8卷 425-427页

作者： Yang yi-yong, li liang-chao, Yuan liang-jie, Sun Ju-tang, Zhang Ke-liCollege of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, China Wuhan University College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

A new structural copper (II) monosalicylate, Cu(OC6H4C02)·H20, was synthesized by the rheological phase reaction method from salicylic acid and copper oxide in 1∶1 mole ratio. The structure was characterized by powder X-ray diffraction, IR and thermogravimetry. The Cu(OC6 H4 CC2)·H20 belongs to monoclinic system, with cell dimension:a=2.136 28(67),b=0. 657 84(22),c=l. 594 09(50) nm, β=108.434(25) ,V=2.125 28(83) nm3,Z=12, Dcalc=2.041 kg·L?1,D obs=2.003 kg·L?1. The crystal water was lost at 96–250°C. The determined magnetic moment and magnetic susceptibility were 1. 947 B. M. and 6. 546×10?6 (287. 20 K), respectively.

关键词： copper monosalicylate rheological phase reaction crystal structure thermal decomposition infrared spectrum