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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 s.In this study,information on the urban expansion process of Chinese coastal cities from the 1970 s to 2013 was retrieved.Through 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 revealed.Results 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 loose.Policies have a powerful significance in terms of guiding urban expansion and its spatial differences in coastal cities.Urban 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

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

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

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

Urban Expansion in China Based on Remote Sensing Technology：A Review

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Chinese Geographical Science 2018年第5期28卷 727-743页

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

Urban areas and its evolution are important anthropogenic indicators and human ecological footprints, and play decisive roles in environmental change analysis, global geo-conditional monitoring, and sustainable development. China has the highest rate of urban expansion and has emerged as an urban expansion hotspot worldwide. In this paper, the progress of studies on Chinese urban expansion based on remote sensing technology are summarized and analyzed from the aspects of urban area definition, remotely sensed imagery applied in urban expansion, monitoring methods of urban expansion, and urban expansion applications. Existing issues and future directions of Chinese urban expansion are discussed and proposed. Results indicate that: 1) The fusion of multi-source remotely sensed imagery is imperative to meet the needs of urban expansion with various monitoring terms and frequencies on different scales and dimensions. 2) To guarantee the classification accuracy and efficiency and describe urban expansion and its influences on local land use simultaneously, the combination of visual interpretation and automatic classification is the tendency of future monitoring methods of urban areas. 3) Urban expansion data have become the prerequisite for recognizing the urban development process, excavating its driving forces, simulating and predicting the future development directions, and also is conducive to revealing and explaining urban ecological and environmental issues. 4) In the past decades, Chinese scholars have promoted the application of remote sensing technology in the urban expansion field, with data construction, methods and models developing from the quotation stage to improvement and innovation stage; however, an independent and consistent urban expansion data on the national scale with long-term and high-frequency(such as annual monitoring) monitoring is still lacking.

关键词：中国城市遥感技术评论自动分类变化分析持续开发世界范围扩大使用

Urban expansion in China and its effect on cultivated land before and after initiating"Reform and Open Policy"

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中国科学：地球科学英文版 2016年第10期59卷 1930-1945页

作者： ZHANG ZengXiang WEN QingKe LIU Fang ZHAO XiaoLi LIU Bin XU JinYong YI Ling HU ShunGuang WANG Xiao ZUO LiJun LI Na LI MinMin shi lifeng ZENG Tian JU HongRun Institute of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Urbanization in China has expanded at an unprecedented speed since the declaration of "Reform and Open Policy"and presented many challenges. Unbalanced regional development, appearance of super megacities and concomitant problems,and conflicts between urbanization and cultivated land protection are three critical problems that Chinese urbanization has to face. To develop new plans for foreseeable future urbanization in China, it is critical to understand the evolving history of cities across China. This study maps urban expansion of 60 typical Chinese cities based on large amount of remote sensing data and the labor-intensive image interpretation method, in order to understand the history of urban expansion from the 1970 s to 2013.Results showed that area of cities expanded 5.23 times compared to their area in the 1970 s. Urban expansion in China accelerated three times(1988–1996, 1999–2006, and 2009–2011) and decelerated three times(1997–1998, 2007–2008, and 2012–2013) over the 40 years. The urban area of South China expanded most significantly 9.42 times, while the urban area in Northeast China expanded only 2.37 times. The disparity among different administrative ranks of cities was even greater than(3.81 times) the differences among different regions. Super megacities have been continuously expanding at a fast rate(8.60-fold), and have not shown obvious signs of slowing down. The proportion of cultivated land among the land sources for urban expansion decreased to a small extent in the 1990 s, but cultivated land continues to be the major land source for urban expansion. Effective future urbanization needs controlling the expansion scale of large cities and reasonably developing medium and small cities, as well as balancing regional development.

关键词：中国南方地区城市扩张耕地保护改革开放引发区域发展发展历史城市面积

Extraction of Basic Trends of Urban Expansion in China over Past 40 Years from Satellite Images

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Chinese Geographical Science 2016年第2期26卷 129-142页

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

If urban sprawl is to be avoided in China in the next ten years, it is not only crucial to understand the overall history, current status, and future trends of urban expansion there, but also these differences, and this is presently lacking. In this study, remotely sensed images with approximately 30 m spatial resolution were used to quantitatively assess the spatial and temporal patterns of urban expansion of 60 Chinese cities(1973–2013). Urban-expansion-process curves of the cities studied were drawn using annual expansion area as an indicator. Curve similarity analysis generated four basic process modes of urban expansion in China. These included cities that: 1) peaked around 2004 and then decelerated; 2) peaked around 2010 and then decelerated; 3) showed sustained acceleration, and 4) showed continued deceleration. Four basic process modes represented cities under different levels of development stage. Geographic location was found to be the most related characteristic to urban expansion process. Regional development policies at the national level in each region also showed highly temporal consistency with fluctuation characteristics of urban expansion process. Urban characteristic such as population size and administrative level were not found to be significantly related to urban expansion-process modes. Understanding the basic process-mode categories well is extremely important for future regional-balance planning and development of macroeconomic policies.

关键词：卫星遥感图像城市扩展城市扩张空间分辨率提取宏观经济政策时间模式中国城市

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 given.The basic states for SJTU-HR1 are proposed,including lying,sitting,standing and handstanding,abstracted from the daily exercises of human beings.The GF(generalized function) set theory is exploited to achieve the kinematic characteristics of the interested EEs(end-effectors) of SJTU-HR1 for the lying states.Finally,the results show that the large amounts of states can be described using the abbreviations in a systematic manner.Although 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