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DOA estimation via sparse recovering from the smoothed covariance vector

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Journal of Systems Engineering and Electronics 2016年第3期27卷 555-561页

作者： Jingjing Cai dan bao Peng Li School of Electronics Engineering Xidian University

A direction of arrival（DOA） estimation algorithm is proposed using the concept of sparse representation. In particular, a new sparse signal representation model called the smoothed covariance vector（SCV） is established, which is constructed using the lower left diagonals of the covariance matrix. DOA estimation is then achieved from the SCV by sparse recovering, where two distinguished error limit estimation methods of the constrained optimization are proposed to make the algorithms more robust. The algorithm shows robust performance on DOA estimation in a uniform array, especially for coherent signals. Furthermore, it significantly reduces the computational load compared with those algorithms based on multiple measurement vectors（MMVs）. Simulation results validate the effectiveness and efficiency of the proposed algorithm.

关键词： array signal processing convex optimization direction of arrival（DOA） estimation sparse representation

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链式回转弹仓区间不确定性动力学模型

兵工学报 2024年第6期45卷 1991-2002页

作者：赵伟侯保林闫少军鲍丹林瑜斌南京理工大学机械工程学院江苏南京210094 南京理工大学瞬态物理国家重点实验室江苏南京210094 内蒙古第一机械集团有限公司内蒙古包头014000

针对具有区间不确定性参数的辨识问题,提出一种基于区间可能度转换模型的区间不确定性参数的双层嵌套辨识(Double-layer Nested Identification,DNI)方法。通过将待辨识参数分为两类,利用DNI方法辨识出第1类确定性参数,再通过基于DNI思... 详细信息

针对具有区间不确定性参数的辨识问题,提出一种基于区间可能度转换模型的区间不确定性参数的双层嵌套辨识(Double-layer Nested Identification,DNI)方法。通过将待辨识参数分为两类,利用DNI方法辨识出第1类确定性参数,再通过基于DNI思想的区间优化方法优化第2类区间不确定性参数的区间范围;面向嵌套策略类型方法计算量庞大且效率低的问题,选用贝叶斯优化-粒子群优化(Bayesian Optimization-Particle Swarm Optimization,BO-PSO)方法作为内层算法以提高求解效率。DNI方法的内层利用BO-PSO方法计算区间上下界,外层利用改进型布谷鸟搜索(Improved Cuckoo Search,ICS)方法辨识特定参数。为进一步缩短求解时间,提出一种ICS多核极限学习机(ICS-Multiple Kernel-Extreme Learning Machine,ICS-MK-ELM)代理模型,ICS-MK-ELM代理模型克服了人工调节每个核函数超参数的困难,并且模型预测精度明显高于核ELM(Kernel ELM,KELM)和MK-ELM;将DNI方法应用于链式回转弹仓的参数辨识,解决了链式弹仓具有区间不确定性参数的辨识困难的问题,参数辨识结果表明所提DNI方法以及基于DNI思想的区间优化方法具有更高的精度和稳定性。

关键词：不确定性区间可能度弹仓参数辨识多核极限学习机贝叶斯优化布谷鸟搜索方法

Dynamic Comprehensive Assessment of Power Development Based on Provincial Data

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CSEE Journal of Power and Energy Systems 2020年第3期6卷 672-680页

作者： Wei Hu Qiuting Guo Yifan Zhou Yi Kang Huanshuai Bing dan bao State Key Lab of Power Systems the Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Central Southern China Electric Power Design Institute China Power Engineering Consulting Group CorporationWuhan 430071China Northeast Branch State Grid Corporation of ChinaShenyang 110180China

Dynamic comprehensive assessment of regional power industry development levels is of paramount importance for understanding the development characteristics and potential of the local power industry.A tri-level evaluation index system is established,describing five aspects of the local power industry development level,specifically,the coordination degree between the power industry and economy/energy,power generation,power consumption,power supply and development potential.A combination of information entropy and the analytic hierarchy process(AHP)is used to establish a static evaluation model,and a blend of subjective opinions and objective data information is then realized.By aggregating the static evaluation model for each time period based on a time-ordered weighting vector calculated using time-ordered information entropy,a dynamic comprehensive evaluation model of power industry development level is established.By considering provincial data from China recorded during 2007 to 2016 as the sample set,through synchronic and diachronic comparisons of the evaluation results,the differences,characteristics and potential of local power industry development in China are explored.

关键词： Analytic hierarchy process development level of power electric industry dynamic comprehensive assessment information entropy

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基于混合策略的机坪车辆主动式实时调度方法

交通运输工程学报 2024年第3期24卷 251-265页

作者：包丹文陈卓姚馨宇周佳怡南京航空航天大学民航学院江苏南京211106

为解决不确定性事件造成的机坪车辆调度扰动问题,提出了一种基于混合策略的机坪车辆主动式实时调度方法;设计了一种考虑机坪分区的灵活运行机制,以允许车辆自适应调整停放区域;建立了一个混合整数规划模型,旨在最小化航班保障请求总响... 详细信息

为解决不确定性事件造成的机坪车辆调度扰动问题,提出了一种基于混合策略的机坪车辆主动式实时调度方法;设计了一种考虑机坪分区的灵活运行机制,以允许车辆自适应调整停放区域;建立了一个混合整数规划模型,旨在最小化航班保障请求总响应时间与机坪车辆总行驶距离;从时空双重维度考虑服务代价,引入车辆时空服务半径指标,设计了基于未来请求信息的灵活等待策略与动态搬迁策略;通过主动式调度策略提高航班保障服务质量,降低服务车辆运行成本,并以北京首都国际机场为实例进行了实证研究。研究结果表明:与传统调度模式相比,灵活运行机制可有效提高车辆运行效率,并缩短空闲车辆折返距离,请求总响应时间与车辆总行驶距离分别下降了37.0%和36.8%;灵活等待策略适用于航班起降密集的高峰时段,车辆总行驶距离缩短了11.6%;动态搬迁策略适用于覆盖范围较广的机坪区域,在请求总响应时间降低17.8%的同时会产生较高的搬迁成本,车辆总行驶距离将增加12.5%。由此可见,针对繁忙的大型枢纽机场,采用混合策略能够在航班保障服务质量与服务车辆运行成本间取得有效平衡。

关键词：航空运输动态车辆路径问题主动式实时调度等待策略搬迁策略机坪车辆

川东北飞仙关高含硫地层油基钻井液复合除硫技术

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钻井液与完井液 2024年第3期41卷 350-356页

作者：肖金裕周华安暴丹汪伟杨兰平江显俊川庆钻探钻井液技术服务公司重庆400021 川庆钻探钻井液技术服务公司成都610056 重庆科技学院化学化工学院重庆401331

川东北地区飞仙关组气藏属于高含硫气藏~特高含硫气藏,针对川东北飞仙关高含硫气藏地质特点和钻井液技术难点分析,提出油基钻井液复合除硫技术对策。通过室内实验优选出除硫效果好的除硫剂,并进行了优选除硫剂复合配方优化研究和除硫剂... 详细信息

川东北地区飞仙关组气藏属于高含硫气藏~特高含硫气藏,针对川东北飞仙关高含硫气藏地质特点和钻井液技术难点分析,提出油基钻井液复合除硫技术对策。通过室内实验优选出除硫效果好的除硫剂,并进行了优选除硫剂复合配方优化研究和除硫剂高温老化除硫效果评价实验。研究表明,复合配方3%YT-3+3%CLC-2+3%JD-2的H_(2)S预防率高达99.14%,清除率达到100%,具有优良的除硫能力,复合配方中的锌基类除硫剂与钻井液中的H_(2)S反应生成稳定的难溶硫化物(ZnS),三嗪类除硫剂和醇醚酰胺类除硫剂主要通过物理和化学反应作用除硫,反应比较迅速,且不可逆,能够去除钻井液中的硫化氢,消除硫化氢对钻井液性能的影响和对钻具的腐蚀。该复合除硫技术在坡005-X4井和坡002-H5井飞仙关高含硫地层现场应用非常成功,在钻进过程中以及起下钻循环排后效期间地面均未检测到H_(2)S气体溢出,钻井液中S2−含量始终监测为零,充分说明复合除硫技术除硫效果显著,能够满足高含硫井钻进的要求,为下川东高含硫气藏钻井工程除硫剂的优选提供良好借鉴。

关键词：飞仙关高含硫地层除硫剂优选复合除硫技术

Effects of kanglaite capsules combined with transcatheter arterial chemoembolization （TACE） on patients with mid or late-stage primary hepatocellular carcinoma （HCC）

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The Chinese-German Journal of Clinical Oncology 2009年第2期8卷 65-68页

作者： Daojun Li Xinhua Xu dan bao Feng Xue Delan Dai The First College of Clinical Medical Science Three Gorges University Yichang 443003 China Department of Oncology Yichang Central People＇s Hospital Yichang 443003 China Oncology Institute Three Gorges University Yichang 443003 China

观察囊与 transcatheter 相结合的 kanglaite (KLT ) 的临床的效果的目的动脉的 chemoembolization (不作声) 在与中间或迟了阶段的主要肝细胞癌(HCC ) 对待病人。65 个盒子随机被划分成 2 个组，的方法在联合组的 32 个病人接受了 KLT ... 详细信息

观察囊与 transcatheter 相结合的 kanglaite (KLT ) 的临床的效果的目的动脉的 chemoembolization (不作声) 在与中间或迟了阶段的主要肝细胞癌(HCC ) 对待病人。65 个盒子随机被划分成 2 个组，的方法在联合组的 32 个病人接受了 KLT 囊 + 的治疗不作声，在控制组的 33 个病人被对待与独自不作声。客观反应率(RR ) ，浆液高山哈 fetoprotein (法新社) ，外部血 T 淋巴细胞亚群(T-LS ) ，生命(QOL ) 的质量，前进(TTP ) 的时间和不利反应在 2 之间被遵守并且比较组。客观反应评估的结果和浆液高山哈 fetoprotein 层次没有在二个组之间的有效差量(P > 0.05 ) 。联合组是优异的在生命(QOL ) 的质量控制组，前进(TTP ) 的时间，外部血 T 淋巴细胞亚群(CD3+ ， CD4+ ， CD4+∖CD8 比率) 并且肝不利反应，与有效差量(P < 0.05 ) 。结论 KLT 囊与结合了不作声是到对待的一个有效方法失去了外科的治疗的机会的主要肝细胞癌(HCC ) 病人。

关键词：肝癌癌细胞临床研究

An Efficient Verification and Test Scheme for Media Broadcasting Demodulator

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An Efficient Verification and Test Scheme for Media Broadcas...

Isorhamnetin Downregulates MMP2 and MMP9 to Inhibit Development of Rheumatoid Arthritis through SRC/ERK/CREB Pathway

2009 IEEE 8th International Conference on ASIC(ASICON 2009)

作者： Yun Chen﹡ Nan Shao Bo Xiang dan bao An Pan Xiaoyang Zeng﹡ IEEE member

For the complex development process of media broadcasting demodulator chip,it is proposed that a low cost,high reliability verification and test scheme at system level in this paper.This scheme emphasizes the collaboration of algorithm simulation,RTL description,FPGA verification,ASIC realization and any other stages of chip development.All these stages constitute an organic,closely interconnected whole.And for the particularity of communication chip,this scheme can solve function verification and performance test,ensure the accuracy,completeness and reliability of the test and verification.Then both the development time and the cost of the product are significantly reduced.This verification and test scheme has been applied to the demodulation chip of the receiver of Chinese broadcasting standard DTMB system.

关键词： Broadcasting Reliability Verification and Test Scheme Low Cost

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Chinese Journal of Integrative Medicine 2024年第4期30卷 299-310页

作者： LIU Xiao-rong LI Shuo-fu MEI Wen-ya LIU Xiang-dan ZHOU Ri-bao College of Pharmacy Hunan University of Chinese MedicineChangsha(410208)China Department of Orthopaedics The First Hospital of Hunan University of Chinese MedicineChangsha(410007)China

Objective To investigate the effect of isorhamnetin on the pathology of rheumatoid arthritis(RA).Methods Tumor necrosis factor(TNF)-α-induced fibroblast-like synoviocytes(FLS)was exposed to additional isorhamnetin(10,20 and 40µmol/L).Overexpression vectors for matrix metalloproteinase-2(MMP2)or MMP9 or SRC were transfected to explore their roles in isorhamnetin-mediated RA-FLS function.RA-FLS viability,migration,and invasion were evaluated.Moreover,a collagen-induced arthritis(CIA)rat model was established.Rats were randomly divided to sham,CIA,low-,medium-,and high-dosage groups using a random number table(n=5 in each group)and administed with normal saline or additional isorhamnetin[2,10,and 20 mg/(kg·day)]for 4 weeks,respectively.Arthritis index was calculated and synovial tissue inflammation was determined in CIA rats.The levels of MMP2,MMP9,TNF-α,interleukin-6(IL-6),and IL-1β,as well as the phosphorylation levels of SRC,extracellular regulated kinase(ERK),and cyclic adenosine monophosphate response element-binding(CREB),were detected in RA-FLS and synovial tissue.Molecular docking was also used to analyze the binding of isorhamnetin to SRC.Results In in vitro studies,isorhamnetin inhibited RA-FLS viability,migration and invasion(P<0.05).Isorhamnetin downregulated the levels of MMP2,MMP9,TNF-α,IL-6,and IL-1βin RA-FLS(P<0.05).The overexpression of either MMP2 or MMP9 reversed isorhamnetin-inhibited RA-FLS migration and invasion,as well as the levels of TNF-α,IL-6,and IL-1β(P<0.05).Furthermore,isorhamnetin bound to SRC and reduced the phosphorylation of SRC,ERK,and CREB(P<0.05).SRC overexpression reversed the inhibitory effect of isorhamnetin on RA-FLS viability,migration and invasion,as well as the negative regulation of MMP2 and MMP9(P<0.05).In in vivo studies,isorhamnetin decreased arthritis index scores(P<0.05)and alleviated synovial inflammation.Isorhamnetin reduced the levels of MMP2,MMP9,TNF-α,IL-6,and IL-1β,as well as the phosphorylation of SRC,ERK,and CREB in synovial tissue(P<0.05).Notably,the inhibit

关键词： rheumatoid arthritis isorhamnetin SRC/ERK/CREB matrix metalloproteinase

How incubation temperature affects hatchling performance in reptiles: an integrative insight based on plasticity in metabolic enzyme

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Current Zoology 2024年第2期70卷 195-203页

作者： dan-Yang Wu Xing-Zhi Han Teng Li bao-Jun Sun Xiao-Yan Qin College of Life and Environment Sciences Minzu University of ChinaBeijing 100081China Key Laboratory of Animal Ecology and Conservational Biology Institute of ZoologyChinese Academy of SciencesBeijing 10011China College of Wildlife and Protected Area Northeast Forestry UniversityHarbin 150040China College of Resources and Environmental Sciences Nanjing Agricultural UniversityNanjing 210095China

Evaluating the effects of temperature variations on animals plays an important role in understanding the threat of climate warming.The effects of developmental temperature on offspring performance are critical in evaluating the effects of warming temperatures on the fitness of ovipa-rous species,but the physiological and biochemical basis of this developmental plasticity is largely unknown.In this study,we incubated eggs of the turtle Pelodiscus sinensis at low(24℃),medium(28℃),and high(32℃)temperatures,and evaluated the effects of developmental temperature on offspring fitness,and metabolic enzymes in the neck and limb muscles of hatchlings.The hatchlings from eggs incubated at the medium temperature showed better fitness-related performance(righting response and swimming capacity)and higher activities of metabolic enzymes(hexokinase,HK;lactate dehydrogenase,LDH)than hatchlings from the eggs incubated at high or low temperatures.In addition,the swimming speed and righting response were significantly correlated with the HK activities in limb(swimming speed)and neck(righting response)muscles,suggesting that the developmental plasticity of energy metabolic pathway might play a role in determining the way incubation temperature affects offspring phenotypes.Integrating the fitness-related performance and the activities of metabolic enzymes,we predict that the P sinensis from high latitude would not face the detrimental effects of climate warming until the average nest temperatures reach 32℃.

关键词： developmental plasticity energetic metabolism enzyme activity hatchling turtle.