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切入场景下基于碰撞风险聚类的改进车速预测方法

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重庆理工大学学报（自然科学） 2024年第1期38卷 67-76页

作者：马彬周世亚姜文龙史立峰赵宇北京信息科技大学机电学院北京100192 新能源汽车北京实验室北京100192 北京电动车辆协同创新中心北京100192 中国人民公安大学交通管理学院北京100038 中国公路车辆机械有限公司北京100010 天津中德应用技术大学汽车与轨道交通学院天津300350

切入工况的高精度车速预测是保证自动驾驶切入安全的关键依据。为提高自动驾驶汽车切入工况安全,开展了基于车车耦合风险聚类的切入场景自车速度高精度预测方法的研究。首先,依据实验所得自然驾驶数据进行车辆切入切出片段提取,使用K-me... 详细信息

切入工况的高精度车速预测是保证自动驾驶切入安全的关键依据。为提高自动驾驶汽车切入工况安全,开展了基于车车耦合风险聚类的切入场景自车速度高精度预测方法的研究。首先,依据实验所得自然驾驶数据进行车辆切入切出片段提取,使用K-means方法依据碰撞风险与加速度关联特征进行聚类分析。其次,基于支持向量机(SVM)模型,对切入切出工况车车交互状态进行在线识别,对切入危险工况进行实时预测。最后,提出基于自回归综合移动平均(ARIMA)模型的改进车速预测方法,结合在线识别结果进行车速在线优化。仿真结果表明,所提出的基于碰撞风险聚类的改进ARIMA车速预测方法对提高切入安全效果明显,较传统的预测方法车辆的碰撞风险降低了10%~20%。研究结果表明,ARIMA模型的改进车速预测方法对提高自动驾驶车切入安全具有重要的研究意义。

关键词：车速预测碰撞风险 K-means聚类支持向量机 ARIMA模型

Optimization of Gas-Flooding Fracturing Development in Ultra-Low Permeability Reservoirs

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Fluid Dynamics & Materials Processing 2024年第3期20卷 595-607页

作者： lifeng Liu Menghe shi Jianhui Wang Wendong Wang Yuliang Su Xinyu Zhuang Tight Oil Research Institute PetroChina Research Institute of Petroleum Exploration&DevelopmentBeijing100083China Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Qingdao266580China Oil&Gas Technology Research Institute Changqing Oilfield CompanyXi’an710018China

Ultra-low permeability reservoirs are characterized by small pore throats and poor physical properties, which areat the root of well-known problems related to injection and production. In this study, a gas injection floodingapproach is analyzed in the framework of numerical simulations. In particular, the sequence and timing of fracturechanneling and the related impact on production are considered for horizontal wells with different fracturemorphologies. Useful data and information are provided about the regulation of gas channeling and possible strategiesto delay gas channeling and optimize the gas injection volume and fracture parameters. It is shown that inorder to mitigate gas channeling and ensure high production, fracture length on the sides can be controlled andlonger fractures can be created in the middle by which full gas flooding is obtained at the fracture location in themiddle of the horizontal well. A Differential Evolution (DE) algorithm is provided by which the gas injectionvolume and the fracture parameters of gas injection flooding can be optimized. It is shown that an improvedoil recovery factor as high as 6% can be obtained.

关键词： Ultra-low permeability reservoir gas injection flooding component simulation fracture parameters intelligent optimization differential evolution

Classification of lying states for the humanoid robot SJTU-HR1

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Science China(Technological Sciences) 2009年第5期52卷 1301-1311页

作者： JiaLun Yang Feng Gao ZhenLin Jin lifeng shi State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China Robotic Research Center Yanshan University Qinhuangdao 066004 China

The humanoid robot SJTU-HR1's concept is introduced and its characteristics tree is *** basic states for SJTU-HR1 are proposed,including lying,sitting,standing and handstanding,abstracted from the daily exercises of human *** GF(generalized function) set theory is exploited to achieve the kinematic characteristics of the interested EEs(end-effectors) of SJTU-HR1 for the lying ***,the results show that the large amounts of states can be described using the abbreviations in a systematic *** we have focused on the application of the GF set theory to humanoid robots,particularly the SJTU-HR1,this methodology can also be applied to quadruped robots and hexapedal robots,especially when the desired tasks are complex.

关键词： SJTU-HR1 GF set motion planning basic states lying states

穿心莲内酯通过抑制Fas/FasL信号轴降低子宫内膜癌Ishikawa/DPP细胞对顺铂的耐药性

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中国肿瘤生物治疗杂志 2024年第2期31卷 154-160页

作者：姚素环史利锋李淑芳董素霞陈萍河南护理职业学院妇产科河南安阳455000 河南护理职业学院附属医院·安阳地区医院妇产科河南安阳455000 安阳市人民医院妇产科河南安阳455000

目的:探讨穿心莲内酯(Andro)调节脂肪酸合成酶(Fas)/脂肪酸合成酶配体(FasL)信号轴对子宫内膜癌Ishikawa细胞顺铂(DDP)耐药性的影响。方法:采用0、5、10、20μg/mL DDP分别处理Ishikawa细胞和顺铂耐药的Ishikawa/DPP细胞,0、5、10、25... 详细信息

目的:探讨穿心莲内酯(Andro)调节脂肪酸合成酶(Fas)/脂肪酸合成酶配体(FasL)信号轴对子宫内膜癌Ishikawa细胞顺铂(DDP)耐药性的影响。方法:采用0、5、10、20μg/mL DDP分别处理Ishikawa细胞和顺铂耐药的Ishikawa/DPP细胞,0、5、10、25、50μmol/L Andro处理Ishikawa/DDP细胞,MTT法检测细胞增殖情况并为后续实验选择合适的给药剂量。将Ishikawa/DDP细胞随机分为对照组、DDP组(DDP干预)、Andro组(DDP、Andro干预)、pcDNA3.1-NC组(转染pcDNA3.1+DDP、Andro干预)、pcDNA3.1-Fas/FasL组(转染pcDNA3.1-Fas/FasL+DDP、Andro干预),24 h后,采用qPCR法检测Fas、FasL mRNA的表达,平板克隆形成实验、Transwell实验和流式细胞术分别检测细胞克隆能力、细胞迁移与侵袭和细胞凋亡,WB法检测增殖细胞核抗原(PCNA)、BAX、Bcl-2、MMP-2、PD-L1、多药耐药蛋白-1(MDR-1)及Fas、FasL蛋白表达。结果:DDP以剂量依赖的方式抑制Ishikawa和Ishikawa/DPP细胞增殖,并且与Ishikawa细胞比较,Ishikawa/DPP细胞对DDP的敏感性更低(均Pshikawa/DPP细胞的增殖(均Pshikawa/DPP细胞中Fas、FasL的表达水平均高于Ishikawa细胞(均Pshikawa/DPP细胞中PD-L1、MDR-1、Fas、FasL mRNA及蛋白表达水平显著升高(P0.05);与DDP组比较,Andro组Ishikawa/DPP细胞中Fas、FasL mRNA表达水平、细胞克隆形成率、迁移与侵袭细胞数、PCNA、Bcl-2、MMP-2、PD-L1、MDR-1、Fas、FasL蛋白表达水平显著降低,BAX蛋白表达水平及凋亡率显著升高(Pshikawa/DPP细胞上述指标变化均被逆转(Pshikawa/DPP细胞增殖、迁移与侵袭,促进凋亡,从而降低细胞对DDP的耐药性。

关键词：穿心莲内酯 Fas/FasL信号轴子宫内膜癌 Ishikawa细胞 Ishikawa/DPP细胞化疗顺铂耐药

A stabilizing model predictive control for networked control system with data packet dropout

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控制理论与应用（英文版） 2009年第3期7卷 281-284页

作者： Zhijun LI Dehui SUN Yuntao shi lifeng WANG Department of Automation North China University of Technology Beijing 100044 China

A constrained model predictive control （MPC） algorithm for networked control system with data packet dropout is proposed in this paper. A buffer is designed to store the predicted control sequence between controller and actuator. It is shown that if the control horizon of MPC is not less than the number of data packets lost continuously, feasibility of MPC at initial time implies asymptotical stability of the closed-loop system. A simulation example illustrates the effectiveness of the proposed approach.

关键词： Networked control system Model predictive control Stability

Genome-wide association study of seedling nitrogen-use efficiency-associated traits in common wheat(Triticum aestivum L.)

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The Crop Journal 2024年第1期12卷 222-231页

作者： Huawei shi Weichong Wang lifeng Gao Jirong Wu Chengmei Hu Huishu Yan Yugang shi Ning Li Youzhi Ma Yongbin Zhou Zhaoshi Xu Jun Chen Wensi Tang Kai Chen Daizhen Sun Yuxiang Wu Ming Chen College of Agriculture Shanxi Agricultural UniversityJinzhong 030801ShanxiChina National Key Facility for Crop Gene Resources and Genetic Improvement Key Laboratory of Biology and Genetic Improvement of Triticeae CropsMinistry of AgricultureInstitute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China

Nitrogen(N)fertilizer application is essential for crop-plant growth and *** genetic loci associated with N-use efficiency(NUE)could increase wheat yields and reduce environmental pollution caused by *** subjected a panel of 389 wheat accessions to N and chlorate(a nitrate analog)treatments to identify quantitative trait loci(QTL)controlling NUE-associated traits at the wheat seedling *** the panel with a 660K single-nucleotide polymorphism(SNP)array,we identified 397 SNPs associated with N-sensitivity index and chlorate inhibition *** SNPs were merged into 49 QTL,of which eight were multi-environment stable QTL and 27 were located near previously reported QTL.A set of 135 candidate genes near the 49 QTL included TaBOX(F-box family protein)and TaERF(ethylene-responsive transcription factor).A Tabox mutant was more sensitive to low-N stress than the wild-type *** developed two functional markers for Hap 1,the favorable allele of TaBOX.

关键词： Wheat NUE Genome-wide association study Nitrogen sensitive index Chlorate inhibition rate

Spatial Differences of Coastal Urban Expansion in China from 1970s to 2013

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Chinese Geographical Science 2015年第4期25卷 389-403页

作者： shi lifeng LIU Fang ZHANG Zengxiang ZHAO Xiaoli LIU Bin XU Jinyong WEN Qingke YI Ling HU Shunguang Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences University of Chinese Academy of Sciences

As the ′economic engines′ of China,coastal cities have developed and expanded considerably since the 1970 *** this study,information on the urban expansion process of Chinese coastal cities from the 1970 s to 2013 was *** the analysis of stage characteristics,spatial expansion modes,influences on land use,centroid shifts,and spatial morphological evolutions,the spatial differences of coastal urban expansion were *** indicate that 1) the expansion stages of southern coastal cities are more complex than those of northern coastal cities,and the expansion ranges and speeds of the former are far higher than those of the latter;2) the spatial expansion of southern coastal cities mostly adopt a single mode,whereas northern coastal cities mostly adopt a mixed mode;3) significant spatial differences in the occupations of different land sources exist between the south and the north along the coastline;4) the centroid of coastal cities tends to migrate toward the coastline,and the centroid shift distances of southern coastal cities are clearly higher than those of northern coastal cities;and 5) the spatial morphology of southern coastal cities tends to be compact,whereas that of northern coastal cities tends to be *** have a powerful significance in terms of guiding urban expansion and its spatial differences in coastal *** expansion in coastal cities will encounter new opportunities and challenges under the guidance of new types of urbanization strategies.

关键词：空间差异中国沿海城市扩展年代城市空间形态沿海城市城市扩张土地利用

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基于槽位相关信息提取的对话状态追踪模型

计算机应用 2023年第5期43卷 1430-1437页

作者：石利锋倪郑威浙江工商大学信息与电子工程学院杭州310018

对话状态追踪(DST)是任务型对话系统中一个重要的模块,但现有的基于开放词表的DST模型没有充分利用槽位的相关信息以及数据集本身的结构信息。针对上述问题,提出基于槽位相关信息提取的DST模型SCELDST(SCE and LOW for Dialogue State T... 详细信息

对话状态追踪(DST)是任务型对话系统中一个重要的模块,但现有的基于开放词表的DST模型没有充分利用槽位的相关信息以及数据集本身的结构信息。针对上述问题,提出基于槽位相关信息提取的DST模型SCELDST(SCE and LOW for Dialogue State Tracking)。首先,构建槽位相关信息提取器(SCE),利用注意力机制学习槽位之间的相关信息;然后,在训练过程中应用学习最优样本权重(LOW)策略,在未大幅增加训练时间的前提下,加强模型对数据集信息的利用;最后,优化模型细节,搭建完整的SCEL-DST模型。实验结果表明,SCE和LOW对SCEL-DST模型性能的提升至关重要,该模型在两个实验数据集上均取得了更高的联合目标准确率,其中在MultiWOZ 2.3(Wizard-of-OZ 2.3)数据集上与相同条件下的TripPy(Triple coPy)相比提升了1.6个百分点,在WOZ 2.0(Wizard-of-OZ 2.0)数据集上与AG-DST(Amendable Generation for Dialogue State Tracking)相比提升了2.0个百分点。

关键词：对话状态追踪注意力机制任务型对话课程学习预训练模型

City Size Distribution and Its Spatiotemporal Evolution in China

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Chinese Geographical Science 2016年第6期26卷 703-714页

作者： shi lifeng ZHANG Zengxiang LIU Fang ZHAO Xiaoli WANG Xiao LIU Bin HU Shunguang WEN Qingke ZUO Lijun YI Ling XU Jinyong Institute of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Based on the National Land Use/Cover Database of China(NLUD-C) in the end of the 1980s(the 1980s,hereafter), 1995, 2000, 2005, and 2010, 665 cities were selected to study the size distribution and its changes of urban lands in China. In this study, the spatiotemporal evolutions of urban land size distribution as well as the influence of administrative-level on these cities were explored by combining urban spatial positions and administrative-levels. Results indicate that: 1) City size distribution using urban lands was more practical and reasonable than using non-agricultural population. 2) In the 1980s, cities with ascending urban land rank were centralized in Eastern China, specially the Changjiang(Yangtze) River Delta, the Zhujiang(Pearl) River Delta, and Beijing-Tianjin-Hebei region. Cities in Central, Western, and Northeast China mainly indicated descending urban land rank. 3) The transfer of national development focus resulted in cities with ascending urban land rank becoming evenly distributed nationwide; however, this trend was slightly centralized around Chengdu, Chongqing, and Wuhan in different periods. 4) During the 1980s to 2010, the proportion of cities with ascending urban land rank in provincial capitals, municipalities, and special administrative regions(high-level cities, hereafter) was consistently higher than those in prefecture- and county-level cities except for 2005–2010. The ranks of the majority of the prefecture- and county-level cities were mainly descending, supported by ascending; the proportion of cities with unchanged rank is small. This study breaks through the bottleneck of traditional research in the area of city size distribution by examining urban land replacing the non-agricultural population. The current study also provides scientific explanation for the healthy and reasonable development of urban land as well as the coordinated development of population urbanization and land urbanization.

关键词：中国城市城市的土地缩放分发空间与时间的进化遥感