The Distribution of Surnames in Xiantao City through Isonymy

The population migration in Hubei Province was frequent in history,accompanied by the migration of surnames,so it is important to study their population surnames.We take Xiantao City as an example to explore the isonymic structure of small and medium-sized cities in Hubei.The surname distributions of 223327 residents registered in 2013 were analyzed in 5 towns and 105 villages of Xiantao.The number of different surnames found was 422.As for surnames,theα-value reflects the influence of ethnic composition on the abundance of surnames.The correlation between the isonymic distance and the geographic distance between villages was calculated and indicated that Euclidean distance was weakly correlated with the geographic distance(r=0.177±0.012),and the isonymic distance increased with the geographical distance.Furthermore,the dendrogram and PCA built from the matrix of Euclidean distances between villages identified a main surname differentiation between the urban and rural areas.

Definition of spatial positions within foraging Greater White-fronted Geese flocks from an individual's perspective:Cost-benefit dynamics change with the distance to flock edge

The costs and benefits of group living are not evenly distributed among individuals that occupy different spatial positions within a group(central or peripheral).However,the definitions of central and peripheral positions may artificially mask the true dynamics of cost and benefit of individuals.Using wintering foraging Greater Whitefronted Geese(Anser albifrons)flocks as our study system,we measured individual spatial position within a flock as distance to the flock edge.First,we tested the effects of distance to edge on the antipredation cost and foraging benefit of individual goose using generalized linear mixed models(GLMMs).Flock size and number of neighbors and their interactions with distance to edge were included as fixed effects in GLMMs.Then we used piecewise regression to determine the threshold value of distance to edge to classify central and peripheral individuals.Our results indicated distance to edge significantly affected percent of time spent on vigilance(vigilance time),percent of time spent on foraging(foraging time)and intake rate(pecks/min),whereas other factors had no effects.We found that the critical distance that predicted changes in behavior was around 2.5 m.Birds 2.5 m or less from the edge of the group were more vigilant,and had less efficient foraging than more central individuals.Behavioral differences between central and peripheral individuals were more easily detected when the birds were classified by the method introduced in this study than by the traditional minimum convex polygon method.Our research provides researchers a dichotomous classification scheme that places individuals into peripheral and central positions from an individual's perspective.

Characteristics of fault zones and their control on remaining oil distribution at the fault edge: a case study from the northern Xingshugang Anticline in the Daqing Oilfield, China

Most major oil zones in the Daqing Oilfield have reached a later,high water cut stage,but oil recovery is still only approximately 35%,and 50%of reserves remain to be recovered.The remaining oil is primarily distributed at the edge of faults,in poor sand bodies,and in insufficiently injected and produced areas.Therefore,the edge of faults is a major target for remaining oil enrichment and potential tapping.Based on the dynamic change of production from development wells determined by the injection-recovery relationship at the edge of faults,we analyzed the control of structural features of faults on remaining oil enrichment at the edge.Our results show that the macroscopic structural features and their geometric relationship with sand bodies controlled remaining oil enrichment zones like the edges of NNE-striking faults,the footwalls of antithetic faults,the hard linkage segments（two faults had linked together with each other to form a bigger through-going fault）,the tips of faults,and the oblique anticlines of soft linkages.Fault edges formed two types of forward microamplitude structures：（1） the tilted uplift of footwalls controlled by inverse fault sections and（2） the hanging-wall horizontal anticlines controlled by synthetic fault points.The remaining oil distribution was controlled by microamplitude structures.Consequently,such zones as the tilted uplift of the footwall of the NNW-striking antithetic faults with a fault throw larger than 40 m,the hard linkage segments,the tips of faults,and the oblique anticlines of soft linkage were favorable for tapping the remaining oil potential.Multi-target directional drilling was used for remaining oil development at fault edges.Reasonable fault spacing was determined on the basis of fault combinations and width of the shattered zone.Well core and log data revealed that the width of the shattered zone on the side of the fault core was less than 15 m in general;therefore,the distance from a fault to the development target should be larger than 15 m.Vertically segmented growth faults should take the separation of the lateral overlap of faults into account.Therefore,the safe distance of remaining oil well deployment at the fault edge should be larger than the sum of the width of shattered zone in faults and the separation of growth faults by vertical segmentation.

Landscape Planning and Design of Urban Park from the Perspective of City Image

The image of the city put forward by Kevin Lynch was applied in the landscape planning and design of urban park in this study.By analyzing the 5 dominant elements in the image of the city,i.e.paths,edges,districts,nodes and landmarks,the concrete application scale of these elements in urban park planning were discussed.

文化距离、友好城市对中国OFDI的影响——基于“一带一路”沿线国家的实证研究

在共建“一带一路”高质量发展的背景下,友好城市关系与文化因素成为独具影响力的关键一环。依据交易成本理论和“外来者劣势”理论,构建了拓展的引力模型评估文化距离和友好城市影响我国OFDI的作用机理以及两者之间的互动机制。实证结果显示,文化距离对我国OFDI有抑制作用,友好城市数量的增加弱化了文化距离对OFDI的负面影响,具有正向调节作用,通过分样本检验进一步发现在文化距离较大的国家中友好城市的正向调节作用不显著,反而在文化距离较小的国家更加有效。据此,中国应推进友好城市网络建设,加强文化交流,促进中国OFDI高质量发展。

Resistance Distance and Kirchhoff Index in Corona and Edge Corona of Two Graphs

Let G_1 and G_2 be vertex-disjoint graphs with n_1 and n_2 vertices,m_1 and m_2 edges,respectively.The corona G_1° G_2 of G_1and G_2 was defined as the graph obtained by taking one copy of G_1and n_1 copies of G_2,and then joining the ith vertex of G_1 to every vertex in the ith copy of G_2.The edge corona G_1° G_2 of G_1 and G_2was defined as the graph obtained by taking one copy of G_1 and m_1copies of G_2,and then joining two end-vertices of the ith edge of G_1to every vertex in the ith copy of G_2.Kirchhoff index of G_1 ° G_2 was obtained in a much simple proof and the resistance distance of G_1 °G_2 is obtained.Furthermore,the Kirchhoff index and the resistance distance of G_1 ° G_2 were obtained.

Spatial and temporal variations of soil moisture in three types of agroforestry boundaries in the Loess Plateau, China

Agroforestry is a ubiquitous landscape on the slopes in Loess Plateau, where soil moisture is a limiting factor for plant growth and development. The spatial and temporal characteristics of soil moisture were studied in three types of agroforestry boundaries： forest-grassland, forest-cropland and shelterbelt-cropland. The result shows that soil moisture content decreased with soil depth increasing from the surface to 110 cm. Soil moisture content differed significantly among the three boundaries all in the rainy season （July-September）, dry season （May-June） and spring （March-April）. The horizontal distribution of soil moisture in different soil layers in the three types of boundaries showed different patterns with line form, wave form, scoop form or ＂W＂ form. The distance of edge influence （DEI） of soil moisture in different types of landscape boundaries was estimated by variance analysis and multiple comparisons. In dry season the DEI in 0-10 cm soil layer was 0.4 H （H, average height of trees）, which ranged from 0.2 H in grassland or in cropland to 0.2 H in forest field for both forest-grassland and forest-cropland boundaries, and 0.7 H （ranged from 0.2 H in cropland to 0.5 H in forest field） for shelterbelt-cropland boundary. In rainy season the DEI at soil depth of 0-110 cm was 0.7 H for the three boundaries. The results indicated that agroforestry type should be carefully selected to maintain soil moisture in land management, especially in restoring degraded land in Loess Plateau.

Landscape Pattern Optimization of Chengdu Based on Modern Garden City

TOptimization of regional landscape pattern is significant for improving function and value of ecosystem,and restraining the expansion of urban layout.Taking Chengdu City for example,this paper applied RS and GIS techniques,landscape indexes and ecological service function evaluation to further analyze the temporal and spatial characteristics of landscape pattern and spatial differences of regional ecological functions,and on this basis,identified the spatial distribution of ecological source lands.Based on the long-term objective of building Chengdu into a modem garden city,this paper applied the accumulative cost distance model and introduced garden city theory to construct regional ecological corridors and ecological nodes,and explored the approaches of optimizing landscape pattern of modem garden city.The results showed that a great deal of arable land has been transferred to construction land in the urbanization;intensity of regional ecological functions showed obvious spatial differences;ecological source lands were mainly distributed in the Longmen Mountain,the Qionglai Mountain,the Changqiu Mountain and the Longquan Mountain;according to actual conditions of the study area,the road ecological corridors,river corridors and agricultural corridors in the layout of "four rings and six radial corridors" were constructed;ecological nodes dominated by intersection,wetland and forest park were formed.This research method and results are significant references for building Chengdu into a modem garden

Spatial-temporal Characteristics and Factors Influencing Commuting Activities of Middle-class Residents in Guangzhou City, China

The middle class in metropolitan Chinese cities has become an important social group. With the rapid development of urbanization and constant advancement of suburbanization, the middle class has increasingly come to influence city traffic. Research into middle-class commuting activities thus has practical significance for improving traffic congestion and reducing the commuting burden in metropolitan cities. Based on a dataset formed by 816 completed surveys, this paper analyzes the commuting mode, time and distance of middle-class residents in Guangzhou City using the descriptive statistical method. The results indicate that private cars are the main commuting mode, followed by public transport. Meanwhile, middle-class residents mainly undertake medium-short time and medium-short distance commuting. The study subsequently uses multilevel logistic regression and multiple linear regression models to analyze the factors that influence commuting mode choice, time and distance. The gender, age, number of family cars, housing source and jobs-housing balance are the most important factors influencing commuting mode choice; housing, population density, jobs-housing balance and commuting mode significantly affect commuting time; and transport accessibility, jobs-housing balance and commuting mode are the notable factors affecting commuting distance. Finally, this paper analyzes what is affecting the commuting activities of middle-class residents and determines the differences in commuting activity characteristics and influence factors between middle-class and ordinary residents. Policy suggestions to improve urban planning and urban management are also proposed.

Analysis of Intra-annual Heterogeneous Characteristics of Precipitation in Shaoguan City

Based on the daily precipitation data between 1965 and 2009 from 8 rainfall stations in Shaoguan City,the indexes of precipitation concentration degree（ PCD） and precipitation concentration period（ PCP） were calculated. And then inverse distance weighted（ IDW） interpolation method was used to analyze the heterogeneous distribution characteristics of inter-annual precipitation by introducing the spatial distribution of annual mean values,variable coefficients,correlation coefficients with annual precipitation,change trends and composite analysis. The results showed that PCD was mainly decreasing from southeast to northwest in spatial distribution,long-term average annual values of PCP were distributed in the first ten days of June at most region. Annual precipitation increased as PCD increased in southern region,but the change trend was the opposite in northern region. Annual precipitation increased as PCP lagged in most region. PCD and PCP mainly appeared upward trend. Composite analysis of PCD in more-precipitation years was similar to less-precipitation years in spatial distribution,but the PCD in less-precipitation years was higher.Seen from the mean in the whole region,PCP in more-precipitation years lagged about 20 days behind those in less-precipitation years. The research can provide basis for the production of agriculture and industry as well as disaster prevention and reduction.

Deep Learning Implemented Visualizing City Cleanliness Level by Garbage Detection

In an urban city,the daily challenges of managing cleanliness are the primary aspect of routine life,which requires a large number of resources,the manual process of labour,and budget.Street cleaning techniques include street sweepers going away to different metropolitan areas,manually verifying if the street required cleaning taking action.This research presents novel street garbage recognizing robotic navigation techniques by detecting the city’s street-level images and multi-level segmentation.For the large volume of the process,the deep learning-based methods can be better to achieve a high level of classifica-tion,object detection,and accuracy than other learning algorithms.The proposed Histogram of Oriented Gradients(HOG)is used to features extracted while using the deep learning technique to classify the ground-level segmentation process’s images.In this paper,we use mobile edge computing to process street images in advance andfilter out pictures that meet our needs,which significantly affect recognition efficiency.To measure the urban streets’cleanliness,our street clean-liness assessment approach provides a multi-level assessment model across differ-ent layers.Besides,with ground-level segmentation using a deep neural network,a novel navigation strategy is proposed for robotic classification.Single Shot Mul-tiBox Detector(SSD)approaches the output space of bounding boxes into a set of default boxes over different feature ratios and scales per attribute map location from the dataset.The SSD can classify and detect the garbage’s accurately and autonomously by using deep learning for garbage recognition.Experimental results show that accurate street garbage detection and navigation can reach approximately the same cleaning effectiveness as traditional methods.

城市职购出行距离的影响因素与优化对策研究——以武汉市为例

职购行为是城市居民重要的消费活动,对其特征及成因的理解有助于完善城市就业中心与商业中心的协调布局,丰富城市生活空间的理论认识。以武汉市为例,运用LBS位置服务数据、抽样调查数据、GIS空间分析与结构方程模型方法,测度职购出行距离,揭示其影响因素。结果表明:武汉城市居民职购活动以中短程出行为主,职购距离的圈层异质性明显,城市边缘及外围地区职购便利性更差。就业地商业可达性、社会经济属性、就业通勤成本、网络购物习惯等是影响职购出行距离的重要因素。应优先对10余处职购不便问题突出的就业集聚区开展优化,既要推动基于多因素协同的综合优化,也要区别不同就业集聚区职购困难的诱致主因,实施分类型、差异化的改进措施。

金属预埋吊件剪切力学性能试验研究

为确定可行的金属预埋吊件(简称预埋吊件)剪切试验方法以及为安全系数提供可靠依据,对100、150mm两种不同边距的预埋吊件混凝土试件进行抗剪试验研究。研究预埋吊件的受剪力学性能,测量楔形体破坏角度,分析荷载-位移曲线,探究混凝土楔形体破坏的抗剪极限承载力与预埋吊件的物理特性之间的关系。结果表明:试验中所有预埋吊件均发生混凝土楔形体破坏,其角度与理想状态下的破坏角度接近;预埋吊件的直径、预埋到混凝土中的深度、预埋吊件轴心到剪力垂直边缘的距离与抗剪极限承载力之间均呈正相关。

上海市郊区地铁站对周边地区的经济效应研究

以上海市外环线外的60个郊区地铁站为研究对象,探讨郊区地铁站对周边地区经济的影响。采用夜间灯光数据,并结合断点回归方法进行分析。结果表明:地铁站的开通对周边地区产生显著的经济效应,这种效应具有显著的距离衰减特性。地铁站半径1200 m以内的区域灯光亮度显著提升,超出此范围则无明显的断点处理效应。此外,这种空间经济效应表现出显著的异质性。对于距离市中心适中的地铁站,地铁开通存在显著的断点处理效应,而对于其他距离分组则不存在。

创新要素集聚与城市间均衡发展:“一城独大”还是“携城发展”

随着区域协调发展战略的深入推进,以创新要素推动城市间均衡发展逐渐成为社会共识。首先从理论层面分析了创新要素集聚对城市间均衡发展的直接影响、作用路径及空间效应,随后基于2011—2021年中国273个城市的面板数据,运用双向固定效应模型、调节路径分析模型等实证评估了创新要素集聚与城市间均衡发展的作用关系。研究发现:(1)创新要素集聚与城市间均衡发展之间存在先“一城独大”后“携城发展”的U型关系;(2)创新创业活跃度能够作为创新要素集聚影响城市间均衡发展的作用桥梁;(3)相较于不与省会、直辖市相邻城市和经济发展落后城市,省会、直辖市或与省会、直辖市相邻城市以及经济发展领先城市的创新要素集聚与城市间均衡发展的U型关系表现得更为明显;(4)创新要素集聚对城市间均衡发展的影响具有显著的空间溢出效应,且该效应存在典型的地理距离衰减特征,600km以内创新要素集聚的溢出效应较强。研究有助于识别创新要素集聚对城市间均衡发展的具体影响,能够为缩小区域发展差距、促进经济高质量发展提供有益借鉴。

面向智慧城市的边缘联邦学习与低开销贡献评估策略

为改善智慧城市中隐私泄露及算力不足的问题,提出了一种融合边缘计算的联邦学习框架,将复杂的计算任务卸载至拥有更强计算和通信能力的边缘服务器上,提高了模型训练的效率,同时也确保了数据隐私的安全。在联邦学习过程中,提出了一种节能且高效的贡献估计算法,旨在激励参与者的持续参与。与现有的贡献估计方法相比,该算法能够有效减少计算和通信开销,并准确地估计各参与者的贡献。

架空导线压接对边距的图像测量方法

压接导线主要应用于架空线路建设,其对边距对线路安全运行及服役期限起到重要作用。针对传统人工测量存在的可靠性差、效率低的缺点,提出了一种基于图像处理的压接对边距测量方法。首先根据图像的累计灰度突变点自动裁剪被测区域并进行中值滤波,然后基于改进Otsu阈值法获得边缘连续的二值图像;再分别使用形态学处理和高斯曲线拟合法对边缘进行二次定位,得到亚像素级边缘点;最后采用基于随机抽样一致性(random sample consensus, RANSAC)的最小二乘拟合方法完成上下边缘点的曲线拟合,实现压接对边距的测量。通过模拟试验表明了RANSAC拟合经过10次迭代后测量算法的效果较好,测量误差小于0.1 pixels;而实际导线测量试验结果表明,改进Otsu算法对光照强度具有适应性,同时与人工测量相比,图像测量方法的最大相对偏差为1.82%,重复标准差提高60%,平均耗时仅为人工测量的1/10,能够实现压接对边距高效可靠的测量。

采用椭圆算法和Canny算子的超声TOF估计方法

椭圆算法被用于测量超声回波信号的渡越时间(TOF),以便估计目标的距离。然而,椭圆算法是将估计出的椭圆长轴位置对应的时间点作为TOF值,估计的目标距离值与实际距离值仍有一定误差。为了进一步提高椭圆算法的TOF估计精确度,将Canny边缘检测引入到椭圆算法中,结合回波脉冲包络的特征形成一种新的超声TOF估计方法。首先利用边缘检测算子提取出近似椭圆形的回波脉冲包络的边界,然后根据边界上点对应的信号幅度用差分方法搜索除起始点以外的梯度最大值位置对应的时间确定为TOF值。实验结果表明:改进后的椭圆算法测量绝对误差可以控制在1.5 mm以内,较传统方法相比至少提高0.5 mm。而相对误差达到0.2%,较传统方法提高了30%。改进后的椭圆算法的应用使得测量的准确性和可靠性均得到了明显提升。

基于多源城市数据的空气质量预测模型

针对目前空气质量预测研究方法只考虑单一站点时序特性的缺陷问题,提出一种基于多源城市数据的STRGNN模型。将相邻站点之间的空间相关性表示为距离图和相似图,根据领域类别对特征分组;将分组特征与构建的距离图和相似图成对组合输入至模型。通过收集邻近信息捕获空气质量的空间相关性,利用叠加多层的卷积捕获空气质量的时间相关性。仿真结果表明,该模型与GRU、Seq2Seq等4个基准模型相比,在1 h-6 h预测的MAE和RMSE分别降低了3%和1%,预测效果有所提升,验证所提方法与现有方法相比具有优越性。

基于SolidEdge模拟瓦楞纸板三维成形的折弯问题研究

目的基于SolidEdge模拟瓦楞纸箱的三维成形效果,通过偏置折弯线,使基于钣金环境的折弯命令按照瓦楞纸箱的需求从开槽中线处折叠。方法提出折弯过程中存在的问题,针对一块简化的瓦楞纸板(尺寸为150 mm×80 mm),从折弯方式、板厚和板的幅面规格等3方面,分析折弯命令对其成形过程的影响,并对折弯线向固定端的偏置距离进行优化。结果折弯方式为"材料外侧"对折弯命令的影响最小,随着板厚的增加对折弯命令的影响加大,且初始偏置距离为0.25t(t为板厚),板的幅面规格对折弯命令无影响。结论将折弯线向固定端偏置0.26t-0.05,可以解决二维向三维成形的折弯问题。