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Nonlinear Control for Multi-agent Formations with Delays in Noisy Environments

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自动化学报 2014年第12期40卷 2959-2967页

作者： LU xiao-Qing WANG Yao-Nan mao Jian-Xu College of Electrical and Information Engineering Hunan University

In this paper, we investigate the nonlinear control problem for multi-agent formations with communication delays in noisy environments and in directed interconnection topologies. A stable theory of stochastic delay differential equations is established and then some sufficient conditions are obtained based on this theory, which allow the required formations to be gained at exponentially converging speeds with probability one for time-invariant formations, time-varying formations, and time-varying formations for trajectory tracking under a special"multiple leaders" framework. Some numerical simulations are also given to illustrate the effectiveness of the theoretical results.

关键词：非线性控制噪声环境多代理随机延迟微分方程延误地层多Agent 时间变化

Modeling mechanism of a novel fractional grey mode based on matrix analysis

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Journal of Systems Engineering and Electronics 2016年第5期27卷 1040-1053页

作者： shuhua mao min zhu xinping yan mingyun gao xinping xiao college of science wuhan university of technologyWuhan 430070China national engineering research center for water transport safety wuhan university of technologyWuhan 430070China

To fully display the modeling mechanism of the novelfractional order grey model （FGM （q,1））, this paper decomposesthe data matrix of the model into the mean generation matrix, theaccumulative generation matrix and the raw data matrix, whichare consistent with the fractional order accumulative grey model（FAGM （1,1））. Following this, this paper decomposes the accumulativedata difference matrix into the accumulative generationmatrix, the q-order reductive accumulative matrix and the rawdata matrix, and then combines the least square method, findingthat the differential order affects the model parameters only byaffecting the formation of differential sequences. This paper thensummarizes matrix decomposition of some special sequences,such as the sequence generated by the strengthening and weakeningoperators, the jumping sequence, and the non-equidistancesequence. Finally, this paper expresses the influences of the rawdata transformation, the accumulation sequence transformation,and the differential matrix transformation on the model parametersas matrices, and takes the non-equidistance sequence as an exampleto show the modeling mechanism.

关键词： fractional order grey model generalized accumulativegeneration matrix decomposition non-equidistance sequence,modeling mechanism.

Dynamic control approaches of spectrum sensing in multi-band cognitive radio networks

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The Journal of China Universities of Posts and Telecommunications 2010年第5期17卷 20-25页

作者： AN chun-yan JI Hong SI Peng-bo mao Xu College of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China College of Electronics Information and Control Engineering Beijing University of Technology Beijing 100022 China

In this paper,the dynamic control approaches for spectrum sensing are proposed,based on the theory that prediction is synonymous with data compression in computational ***,a spectrum sensing sequence prediction scheme is proposed to reduce the spectrum sensing time and improve the throughput of secondary *** use Ziv-Lempel data compression algorithm to design the prediction scheme,where spectrum band usage history is *** addition,an iterative algorithm to find out the optimal number of spectrum bands allowed to sense is proposed,with the aim of maximizing the expected net reward of each secondary user in each time ***,extensive simulation results are shown to demonstrate the effectiveness of the proposed dynamic control approaches of spectrum sensing.

关键词： spectrum sensing sequence optimal number of spectrum bands cognitive radio networks Ziv-Lempel algorithm

Does delaying ureteral stent placement lead to higher rates of preoperative acute pyelonephritis during pregnancy?

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World Journal of Clinical Cases 2022年第3期10卷 802-810页

作者： mao-mao He xiao-Ting Lin Ming Lei xiao-Lan Xu Zhi-Hui He Department of Obstetrics and Gynecology The First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510120Guangdong ProvinceChina Department of Urology The First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510120Guangdong ProvinceChina

BACKGROUND Pregnancy with renal colic may cause pyelonephritis,decreased renal function,systemic infection and even shock in pregnant women,and cause premature birth and other adverse pregnancy *** surgery is necessary,the relationship between timing of the operation and the outcome of the mother and child are not *** To investigate the association between time to ureteral stent placement and clinical outcomes of patients with renal colic during *** In this retrospective study,pregnant women with renal colic who underwent surgery were *** preoperative acute pyelonephritis(PANP),pregnancy outcome,and length of hospital stay(LOS)were compared between the two *** 100 patients were included in the analysis,median age was 30 *** time to ureteral stent placement was 48 h(interquartile range,25-96 h),and 32 patients(32%)were diagnosed with *** was closely related to hospitalization costs,re-admission to the hospital due to urinary tract infection after surgery and premature *** analysis found that stone location and time from pain to admission were related to *** Both early and delayed surgery are safe and effective for the treatment of renal colic during *** surgery may be superior to a delayed procedure due to shorter *** pregnant patients with renal colic,delayed surgery within 48 h is not related to the clinical outcome of the mother and ***,the time from pain to hospital admission was related to PANP.

关键词： Renal colic Ureteral stent placement Acute pyelonephritis Pregnancy

Determination of minimum flood flow for regeneration of floodplain forest from inundated forest width-stage curve

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Water Science and Engineering 2010年第3期3卷 257-268页

作者： Song-hao SHANG xiao-min mao State Key Laboratory of Hydroscience and Engineering Department of Hydraulic Engineering Tsinghua University Beijing 100084 P. R. China College of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 P. R. China

Floods are essential for the regeneration and growth of floodplain forests in arid and semiarid regions. However, river flows, and especially flood flows, have decreased greatly with the increase of water diversion from rivers and/or reservoir regulation, resulting in severe deterioration of floodplain ecosystems. Estimation of the flood stage that will inundate the floodplain forest is necessary for the forest＇s restoration or protection. To balance water use for economic purposes and floodplain forest protection, the inundated forest width method is proposed for estimating the minimum flood stage for floodplain forests from the inundated forest width-stage curve. The minimum flood stage is defined as the breakpoint of the inundated forest width-stage curve, and is determined directly or analytically from the curve. For the analytical approach, the problem under consideration is described by a multi-objective optimization model, which can be solved by the ideal point method. Then, the flood flow at the minimum flood stage （minimum flood flow）, which is useful for flow regulation, can be calculated from the stage-discharge curve. In order to protect the forest in a river floodplain in a semiarid area in Xinjiang subject to reservoir regulation upstream, the proposed method was used to determine the minimum flood stage and flow for the forest. Field survey of hydrology, topography, and forest distribution was carried out at typical cross sections in the floodplain. Based on the survey results, minimum flood flows for six typical cross sections were estimated to be between 306 m3/s and 393 m3/s. Their maximum, 393 m3/s, was considered the minimum flood flow for the study river reach. This provides an appropriate flood flow for the protection of floodplain forest and can be used in the regulation of the upstream reservoir.

关键词： floodplain forest regeneration flow minimum flood stage inundated forest width method ideal point method

Effects of shot peening and laser remelting on oxygen-permeation treatment of titanium alloy

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中国有色金属学会会刊：英文版 2004年第z1期14卷 268-273页

作者： MA Hong-yan WANG mao-cai WEI Zheng XIN Gong-chun State Key Laboratory for Corrosion and Protection Institute of Metal Research Graduate School of Chinese Academy of Sciences Beijing 100030 China State Key Laboratory for Corrosion and Protection Institute of Metal Research Graduate School of Chinese Academy of Sciences Beijing 100030 China Shenyang Liming Aero-engine Group Corporation Shenyang 110043 China Shenyang Liming Aero-engine Group Corporation Shenyang 110043 China

The influence of surface pre-treatments, shot-peening (SP) and laser remelting (LR), on oxygen permeation behaviors of titanium alloy TC11 was investigated. Optical microscope, SEM with EDAX, XRD, and microhardness tester were employed to characterize the microstructure, composition and hardness of this alloy. The results show that the surface roughness is increased by shot-peening, and the microstructure with fine-grain can be obtained by LR pre-treatment. The pre-treated samples were oxygen-permeated at (810± 10) ℃ for 10 h in atmospheric air. The outer layer consists essentially of TiO2, trace Ti2 N, Ti3Al and Ti3AlN for the SP pre-treatment and thin oxygen solution layer is found in the subsurface layer. As for LR pre-treatment, the outer layer consists mainly of TiO2 and small amounts of TiO, and the inner layer consists of alpha crystals, rich in interstitial atoms. Samples by LR pre-treatment has thicker hardened layer with higher hardness values in comparison with SP pre-treated *** boost diffusion of oxygen and hardening mechanisms were discussed based on the experimental results.

关键词： shot peening laser remelting oxygen-permeation titanium solution

Suspected cerebrovascular air embolism during endoscopic esophageal varices ligation under sedation with fatal outcome: A case report

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World Journal of Clinical Cases 2022年第1期10卷 371-380页

作者： Cuo-mao-Ji Zhang xiao Wang Department of Anesthesiology West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Air embolism is a very rare,yet serious and potentially fatal complication of digestive endoscopic *** embolism is the result of air directly entering the arteries or ***,to recognize neurological dysfunction under sedation can be ***,it is extremely important to identify high-risk groups and take preventive *** SUMMARY Herein,we report a 74-year-old female patient with esophageal varices who suffered from consciousness disturbance after the third endoscopic ligation of esophageal varices under *** with the patient’s imaging examination results and medical history,we highly suspected that the patient had developed paradoxical cerebral air embolism during endoscopic *** learned that the patient died at a later *** order to be able to identify and prevent the occurrence of air embolism early,we summarize and analyze the risk factors,pathogenesis,clinical manifestations,prevention and treatment options of gastrointestinal endoscopy complicated by cerebral air *** Electroencephalographic monitoring helps to recognize the occurrence of air embolism in time and increase the patient's chance of survival.

关键词： Cerebral infarction Paradoxical air embolism Endoscopic ligation Esophageal variceal Sedation Case report

A new bisbenzylisoquinoline alkaloid from Plumulanelumbinis

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Chinese Chemical Letters 2016年第12期27卷 1755-1758页

作者： xiao-xiao Zhang Shuang-ChengMa Peng mao Ya-Dan Wang Beijing University of Chinese Medicine Beijing 100029 China National Institutes for Food and Drug Control Beijing 100050 China Shaanxi Momentum Pharmaceutical Co. LTD Xi'an 710075 China

One new bisbenzylisoquinoline alkaloid, neferine N-oxide （1）, along with three known compounds, neferine （2）, liensinine （3）, and isoliensinine （4）, were isolated from Plumulanelumbinis - the embryo of the seed of Nelumbonucifera. Their structures were elucidated by extensive spectroscopic analysis （MS, UV, IR, NMR）, and the absolute configurations were determined by experimental circulardichroism （CD） spectra. Compound 1 is a new naturally occurring bisbenzylisoquinoline alkaloid with an N-oxide functionality, and the CD spectrum of （1R, 1＇R） neferine is first reported. The antioxidant activities of compounds 1-4 were evaluated using the ORAC assay, which illustrated that all these compounds showed the different levels of oxygen radical absorbance capacity.

关键词： Plumulanelumbinis Bisbenzylisoquinoline alkaloid Neferine N-oxide ORAC assay Antioxidative activity

Interleukin-17A facilitates tumor progression via upregulating programmed death ligand-1 expression in hepatocellular carcinoma

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 176-198页

作者： Zhong-Xia Yang Li-Ting Zhang xiao-Jun Liu Xue-Bin Peng xiao-Rong mao The First School of Clinical Medicine Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Department of Infectious Diseases The First Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Department of Radiotherapy Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina

BACKGROUND Hepatocellular carcinoma(HCC)is an inflammation-associated tumor with a dismal *** has become an important treatment strategy for HCC,as immunity is closely related to inflammation in the tumor *** regulates the expression of programmed death ligand-1(PD-L1)in the immunosuppressive tumor microenvironment and affects im-munotherapy ***-17A(IL-17A)is involved in the remodeling of the tumor microenvironment and plays a protumor or antitumor role in different *** hypothesized that IL-17A participates in tumor progression by affe-cting the level of immune checkpoint molecules in *** upregulation of PD-L1 expression in HCC cells by IL-17A was assessed by reverse transcription PCR,western blotting,and flow *** studies were conducted with gene knockout models and pathway *** function of IL-17A in immune evasion was explored through coculture of T cells and HCC *** effects of IL-17A on the malignant biological behaviors of HCC cells were evaluated in vitro,and the antitumor effects of an IL-17A inhibitor and its synergistic effects with a PD-L1 inhibitor were studied in *** IL-17A upregulated PD-L1 expression in HCC cells in a dose-dependent manner,whereas IL-17A receptor knockout or treatment with a small mothers against decapentaplegic 2 inhibitor diminished the PD-L1 expression induced by ***-17A enhanced the survival of HCC cells in the coculture ***-17A increased the viability,G2/M ratio,and migration of HCC cells and decreased the apoptotic *** D1,VEGF,MMP9,and Bcl-1 expression increased after IL-17A treatment,whereas BAX expression *** combination of IL-17A and PD-L1 inhibitors showed synergistic antitumor efficacy and increased cluster of differentiation 8+T lymphocyte infiltration in an HCC mouse *** IL-17A upregulates PD-L1 expression via the IL-17A receptor/phosphorylation-small mothers against

关键词： Interleukin-17A Programmed death ligand-1 Interleukin-17A receptor Small mothers against decapentaplegic 2 Hepatocellular carcinoma Immunotherapy