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基于高阶控制器设计的线性自抗扰控制参数调整

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控制理论与应用 2017年第2期34卷 265-272页

作者：傅彩芬谭文华北电力大学控制与计算机工程学院北京102206

将反馈控制器/扩张状态观测器闭环极点配置在同一位置是线性自抗扰控制器(linear active disturbance rejection control,LADRC)最常用的整定方法.该方法只需调整两个参数,在工程应用上极为方便.但是,由于极点配置在同一位置的限制,整定... 详细信息

将反馈控制器/扩张状态观测器闭环极点配置在同一位置是线性自抗扰控制器(linear active disturbance rejection control,LADRC)最常用的整定方法.该方法只需调整两个参数,在工程应用上极为方便.但是,由于极点配置在同一位置的限制,整定的LADRC可能达不到期望的性能.本文提出以现有控制器参数为基础的LADRC调参方法.该方法以现有控制器参数为基础,通过降阶及逼近,保证LADRC控制能接近现有控制系统的性能.仿真设计表明采用高阶控制器设计的LADRC可以取得与原有控制系统相当的控制性能.该方法不受带宽法调参的需使反馈控制器及扩张观测器极点配置在同一位置的限制,因此可以期望获得比带宽法更好的性能.同时,该方法为已经熟悉掌握其他控制器设计方法的工程控制人员提供了一种便捷的调整线性自抗扰控制参数的方案,具有较好的应用价值.

关键词：线性自抗扰控制参数调整带宽降阶近似高阶控制器

模拟“机架空过”对CSP铌微合金钢组织演变的影响

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钢铁 2010年第6期45卷 54-58页

作者：谭文韩斌武汉钢铁(集团)公司研究院湖北武汉430080

为了能给CSP轧制含Nb、V微合金钢时采用的"机架空过"工艺提供理论指导,在采用实测轧制数据验证组织演变模型的基础上,模拟了F2和F3机架空过工艺对组织演变和平均流变应力(MFS)的影响。结果表明:对模拟的钢种,与无空过道次轧制工艺相比,... 详细信息

为了能给CSP轧制含Nb、V微合金钢时采用的"机架空过"工艺提供理论指导,在采用实测轧制数据验证组织演变模型的基础上,模拟了F2和F3机架空过工艺对组织演变和平均流变应力(MFS)的影响。结果表明:对模拟的钢种,与无空过道次轧制工艺相比,在不降低道次温度的情况下,采用F2机架空过时,可避免混晶,且各道次平均流变应力波动较小。而采用F3空过时,易产生混晶,平均流变应力波动较大。

关键词： CSP 机架空过组织演变平均流变应力模拟

入世前后我国棉花国际贸易影响因素的比较分析

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国际贸易问题 2005年第7期 24-29页

作者：谭砚文温思美华南农业大学经济管理学院

本文运用格兰杰因果关系检验法对入世前后影响我国棉花国际贸易行为的诸因素进行了甄别和计量分析,研究表明在入世前我国棉花垄断经营时期,棉花的进出口只关注供给层面而忽视需求层面,并随着生产量和库存量的变化而波动,而入世以后我国... 详细信息

本文运用格兰杰因果关系检验法对入世前后影响我国棉花国际贸易行为的诸因素进行了甄别和计量分析,研究表明在入世前我国棉花垄断经营时期,棉花的进出口只关注供给层面而忽视需求层面,并随着生产量和库存量的变化而波动,而入世以后我国棉花国际贸易波动则主要是受市场价格及需求因素的影响。

关键词：棉花入世比较分析影响因素国际贸易因果关系检验法计量分析贸易行为垄断经营需求因素市场价格贸易波动格兰杰进出口库存量生产量供给

THE STRUCTURE OF INVERTIBLE SUBSTITUTIONS ON A THREE-LETTER ALPHABET

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Analysis in Theory and Applications 2003年第4期19卷 365-382页

作者： tan Bo wen Zhixiong Zhang Yiping (Wuhan University,China) Department of Mathematics Wuhan University Wuhan Hubei P. R. China

We study the structure of invertible substitutions on three-letter alphabet. We show that there exists a finite set S of invertible substitutions such that any invertible substitution can be written as I wσ 1σ 2…σ k,where I w is the inner automorphism associated with w, and σ j∈ S for 1≤j≤k. As a consequence,M is the matrix of an invertible substitution if and only if it is a finite product of non-negative elementary matrices.

关键词： invertible substitution indecomposable substitution combinatorics of words

Magnetic resonance imaging-based deep learning model to predict multiple firings in double-stapled colorectal anastomosis

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World Journal of Gastroenterology 2023年第3期29卷 536-548页

作者： Zheng-Hao Cai Qun Zhang Zhan-Wei Fu Abraham Fingerhut Jing-wen tan Lu Zang Feng Dong Shu-Chun Li Shi-Lin Wang Jun-Jun Ma Department of General Surgery Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Shanghai Minimally Invasive Surgery Center Shanghai 200025China School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 201100China Department of Radiology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China

BACKGROUND Multiple linear stapler firings during double stapling technique(DST)after laparoscopic low anterior resection(LAR)are associated with an increased risk of anastomotic leakage(AL).However,it is difficult to predict preoperatively the need for multiple linear stapler cartridges during DST *** To develop a deep learning model to predict multiple firings during DST anastomosis based on pelvic magnetic resonance imaging(MRI).METHODS We collected 9476 MR images from 328 mid-low rectal cancer patients undergoing LAR with DST anastomosis,which were randomly divided into a training set(n=260)and testing set(n=68).Binary logistic regression was adopted to create a clinical model using six *** sequence of fast spin-echo T2-weighted MRI of the entire pelvis was segmented and ***-image and clinical-image integrated deep learning models were constructed using the mask region-based convolutional neural network segmentation tool and three-dimensional convolutional ***,specificity,accuracy,positive predictive value(PPV),and area under the receiver operating characteristic curve(AUC)was calculated for each *** The prevalence of≥3 linear stapler cartridges was 17.7%(58/328).The prevalence of AL was statistically significantly higher in patients with≥3 cartridges compared to those with≤2 cartridges(25.0%vs 11.8%,P=0.018).Preoperative carcinoembryonic antigen level>5 ng/mL(OR=2.11,95%CI 1.08-4.12,P=0.028)and tumor size≥5 cm(OR=3.57,95%CI 1.61-7.89,P=0.002)were recognized as independent risk factors for use of≥3 linear stapler *** performance was better with the integrated model(accuracy=94.1%,PPV=87.5%,and AUC=0.88)compared with the clinical model(accuracy=86.7%,PPV=38.9%,and AUC=0.72)and the image model(accuracy=91.2%,PPV=83.3%,and AUC=0.81).CONCLUSION MRI-based deep learning model can predict the use of≥3 linear stapler cartridges during DST anastomosis in laparoscopic LAR *** model might h

关键词： Deep learning Image-reading artificial intelligence Magnetic resonance imaging Predictive model Double stapling technique Linear stapler Rectal cancer Laparoscopic surgery Low anterior resection Anastomotic leakage

Native proteomic analysis for cellular proteins by nondenaturing 2DE and wholegel MS mapping

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Native proteomic analysis for cellular proteins by nondenatu...

光催化剂Sm_2FeSbO_7的制备及光物理和光催化性能表征（英文）

2018年中国质谱学术大会（CMSC2018）

作者： Ya Jin Jun Zhang Takashi Manabe wen tan Institute of Biomedical and Pharmaceutical Sciences Guangdong University of Technology Dermatology Hospital Southern Medical University Faculty of Science Ehime University

Nondenaturing 2 DE is a technique of almost the highest resolution for separating proteomic samples under native conditions. The retained structures and interactions of proteins in the gel, if could be unveiled, would greatly facilitate understanding on composition and functions of the proteomes. However, the present detection methods for the 2 DE-separated proteins could not have satisfying performance for this purpose. For example, the methods of dye staining followed by spot picking and MS identification is often limited in sensitivity and ability to differentiate overlapped proteins, while Western blotting relies on availability of antibodies and has very low throughput. Here we report on our method development for MS mapping of nondenaturing 2 DE-separated cellular proteins and the therefore enabled large-scale interaction analysis. Soluble proteins of human bronchial smooth muscle cells(HBSMC) were separated by nondenaturing micro 2 DE and a 30 mm × 40 mm area was cut into 1.1 mm × 1.1 mm squares, then the 972 square gel pieces were analyzed with standardized procedures of in-gel digestion and quantitative LC-MS/MS. Totally 4323 proteins were identified and the quantity distribution of each was reconstructed as a color density pattern(a native protein map). As expected, many proteins showed distributions not restricted in a single focused area, suggesting protein interactions were widely present in the cellular protein system. Since the proteins comprising a protein complex are expected to migrate together under the nondenaturing separation and result in similar maps, we developed an algorithm and corresponding computer programs to calculate an "overlap factor" of each protein map against each of the other protein maps. Maps of 2328 proteins that were detected in 3 or more squares were subjected to this evaluation, resulting in a 2328 × 2328 matrix of overlap factors. From the matrix, 431 protein pairs showed overlap factors over 0.65 from both protein sides,

关键词： native cellular proteomics MS mapping protein interactions nondenaturing 2DE LC-MS/MS

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无机化学学报 2018年第11期34卷 1950-1965页

作者：栾景飞谭文成南京大学环境学院污染控制与资源化研究国家重点实验室南京210023

首次采用固相反应法制备了新型光催化剂Sm_2FeSbO_7,有效地降解了水中有机污染物。利用X射线衍射、扫描电镜、X射线光电子能谱、傅里叶变换红外光谱、透射电子显微镜和紫外-可见光谱仪对Sm_2FeSbO_7的结构和光催化性能进行了表征。Sm_2F... 详细信息

首次采用固相反应法制备了新型光催化剂Sm_2FeSbO_7,有效地降解了水中有机污染物。利用X射线衍射、扫描电镜、X射线光电子能谱、傅里叶变换红外光谱、透射电子显微镜和紫外-可见光谱仪对Sm_2FeSbO_7的结构和光催化性能进行了表征。Sm_2FeSbO_7为烧绿石型结构,立方晶系和空间群Fd3m结晶。Sm_2FeSbO_7的晶格参数a为1.035 434 nm。Sm_2FeSbO_7的带隙经估算为2.46 eV。用Sm_2FeSbO_7作为光催化剂在可见光照射下降解靛蓝胭脂红,并与氮掺杂Ti O_2对比。结果表明,与掺氮TiO_2相比,Sm_2FeSbO_7在可见光照射下光催化降解靛蓝胭脂红显示出较高的光催化活性。总有机碳的减少,无机产物的逐渐形成,SO_4^(2-)和NO_3^-以及CO_2的演变揭示了在光催化过程中靛蓝胭脂红的连续矿化。检测了一些来自光催化降解靛蓝胭脂红的中间体,如邻硝基苯甲酸和邻硝基苯甲醛,并获得了可能的靛蓝胭脂红光催化降解路径。

关键词：催化作用 Sm2FeSbO7 光催化降解可见光照射光降解路径靛蓝胭脂红

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一种用于机组组合问题的改进双重粒子群算法

中国电机工程学报 2012年第25期32卷 189-195,26页

作者：李整谭文秦金磊华北电力大学河北省保定市071003

为了更经济快速地解决机组组合问题,提出一种改进双重粒子群优化(particle swarm optimization,PSO)算法,包含离散部分和连续部分。离散PSO分时段优化机组的启停状态,在种群更新时加入了临界算子,改进了可行解的判别条件,各机组出力最... 详细信息

为了更经济快速地解决机组组合问题,提出一种改进双重粒子群优化(particle swarm optimization,PSO)算法,包含离散部分和连续部分。离散PSO分时段优化机组的启停状态,在种群更新时加入了临界算子,改进了可行解的判别条件,各机组出力最低值的和要在一定程度上低于负荷需求值,并考虑机组启停时间的向前继承和向后约束。连续PSO用于启停状态确定过程中和确定后的负荷分配,考虑功率平衡约束、热备用约束和机组的出力上下限约束。求解经济负荷分配时,利用罚函数的方法满足机组的爬坡速率约束,最后得到煤耗最小值。采用2个24时段的算例进行仿真,实验结果表明新算法减少了搜索量,提高了收敛速度,并为机组组合问题提出了新思路。

关键词：机组组合双重粒子群优化分时段临界算子罚函数

Value of a virtual hepatic segment model in assisting in the ultrasonic localization of intrahepatic lesions

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Chinese Medical Journal 2013年第23期126卷 4417-4422页

作者： CHENG Guo GUO Yan-li ZHONG Chun-yan tan Li-wen ZHANG Shao-xiang Department of Ultrasound Southwest Hospital Third Military Medical University Chongqing 400038 China Third Military Medical University Chongqing 400038 China

Background During scanning of the right hypochondrium and right intercostal regions with an ultrasonic transducer,several ultrasonic images of oblique sections are *** is still a challenge for ultrasonography to divide these nonconventional sections into an accurate hepatic segmentation *** aim of this research was to investigate the value of the virtual hepatic segment model （VHSM） in assisting the ultrasonic localization of space-occupying hepatic *** VHSM was constructed via 3D reconstruction according to the first Chinese visible human *** ultrasonography,contrast-enhanced CT scan and VHSM techniques were performed in 100 patients with spaceoccupying focal lesions in the liver parenchyma for segmental *** results of these three techniques were compared with the operative *** VHSM was successfully detected on 2D sectional images by 3D reconstruction through surface rendering and volume *** model could simulate ultrasonic directions to conduct a virtual dissection on any section plane,and fine liver segmentation could be displayed in any virtual *** 100 patients,there were 112 liver space-occupying focal lesions distributed in 148 liver *** the positioning accuracies for lesions of different sizes and the lesion segmental distribution accuracies estimated using the three methods mentioned above,ultrasonography exhibited a significantly lower accuracy than VHSM for the segmental localization of lesions （P ＜0.05）,and contrast-enhanced CT was not significantly different from ultrasonography plus VHSM （P ＞0.05）.Conclusion VHSM increased the accuracy of ultrasonic localization of space-occupying hepatic lesions,particularly in hepatic hypovascular regions.

关键词： ultrasonography hepatic lesions hepatic segments 3D reconstruction Chinese visible human