Industrial arrangement of large-scale, non-grid-connected wind power industrial zones in coastal areas of China

Constructing an industrial system for a large-scale,non-grid-connected wind power industry is a key step towards the diverse utilization of wind power.However,wind power exploitation is not only a technical challenge but an industrial problem as well.The objective of this study is to introduce a concept of large-scale,non-grid-connected wind power(LSNGCWP) industrial zones and establish an evaluation model to assess their industrial arrangement.The data of wind energy,industry,nature resources and socio-economy were collected in this study.Using spatial overlay analysis of geographic information system,this study proposes a spatial arrangement of the LSNGCWP indus-trial zones in the coastal areas of China,which could be summarized as the ’one line and three circles’ structure,which will contribute to the optimization of the industrial structure,advance the wind power technology,coordinate the multi-industrial cooperation,and upgrade the industrial transformation of China’s coastal areas.     

Earthquake interaction forces between two structures of different rigidities

A combined structure is assumed to be composed of a rigid part and a flexible part. Each component structure would have a different period of natural vibration if it were built independently. When they are combined in one structure and subjected to an earthquake, there must be generated some interaction forces so that the component structures will have a common vibration. In this paper is an analytical method described to evaluate such interaction forces The general principle is as follows. For each of the component structures, equations of motion taking account of the unknown interaction forces are derived first. Then by eliminating the interaction forces, equations of motion of the combined structure are obtained. After solving these equations and substituting the solution into the equations of motion of the component structures, the unknown interaction forces are obtained directly In the present paper, two structures corresponding to two-degree elastic systems are considered; numerical examples also are included.     

Exploring the relationship between street centrality and land use in Stockholm

This paper examines the relationship between different street centralities and land-use types in Stockholm. Major centrality measures of closeness, betweenness, and straightness are calculated at both global and local levels in both the primary and dual representations of the urban street network. Adaptive kernel density estimation is adopted to transform all unevenly distributed datasets to one continuous raster framework for further analysis. After computing statistical and spatial distribution of each centrality and land-use density map, we find that the density of each street centrality is highly correlated with one type of land use. Results imply that various centralities representing street properties from different aspects can capture the land development patterns of different land-use types by reflecting human activities, and are consequently important indicators to describe urban structure.     

Exploring job centers by accessibility using fuzzy set approach: the case study of the Columbus MSA

When comparing accessibility, the interpretation of results is complex because of lack of standard or universal norm. This uncertainty issue of the distinction from the lack of standard can be solved using the multi-level approach of fuzzy set: universal, relative, and absolute index. Since a fuzzy set approach deals with the vagueness and indiscernibility of accessibility index, the proposed approach suggests a better solution to classify the index than a crisp set or even a single-level fuzzy set approach. In this study, we evaluate job accessibility of locations in the Columbus MSA in Ohio, USA for 18 worker groups. The uncertain distinction between strong/weak, rich/poor, and higher/lower accessibility is improved by the multi-level approach. Moreover, this study attempts to enhance our understanding of spatial structure of job accessibility disaggregated by occupation type and gender.     

海洋水色遥感产品在青海湖鱼产潜力估算中的应用

鱼产潜力可为渔业资源保护和管理提供科技支撑,传统的鱼产潜力估算方法在大型湖泊中往往成本高、采样率低、时效差.本研究基于2018—2020年非冰封期(5—10月)在青海湖的实测数据,通过提取和校对海洋水色遥感MODIS卫星数据反演产品(1 km分辨率)并结合垂向归纳模型(VGPM)构建了青海湖浮游植物初级生产力及鱼产潜力估算模型,估算的浮游植物初级生产力与实测值对比的平均相对误差小于25%.利用该模型估算2018—2020年非冰封期青海湖基于浮游植物初级生产力的鱼产潜力并分析其时空分布规律,结果显示青海湖鱼产潜力在5—10月呈现先增加后减少的季节波动规律,最大值出现在夏季(7—8月);空间分布上呈现湖心小,岸边及靠近入湖支流河口区域大的分布状态,全湖总鱼产潜力月均变化范围为2.5万~17.6万t.鱼产潜力的时空分布规律主要受气温、外源营养物质、裸鲤摄食等影响.研究表明青海湖非冰封期的鱼类资源承载力年累计值可达45.8万t,明显高于现有裸鲤资源的现存量和历史产量高峰值,表明青海湖仍然具备很大的鱼类资源承载力与增殖空间.本研究为同类型的大型高原湖泊基于卫星遥感的高效长期鱼产潜力监测估算提供了范例,为青海湖“封湖育鱼”政策制定和增殖放流保护决策提供参考.     

A scattering-based over-land rainfall retrieval algorithm for South Korea using GCOM-W1/AMSR-2 data

Heavy summer rainfall is a primary natural disaster affecting lives and properties in the Korean Peninsula. This study presents a satellite-based rainfall rate retrieval algorithm for the South Korea combining polarization-corrected temperature (PCT) and scattering index (SI) data from the 36.5 and 89.0 GHz channels of the Advanced microwave Scanning Radiometer 2 (AMSR-2) onboard the Global Change Observation Mission (GCOM)-W1 satellite. The coefficients for the algorithm were obtained from spatial and temporal collocation data from the AMSR-2 and groundbased automatic weather station rain gauges from 1 July - 30 August during the years, 2012-2015. There were time delays of about 25 minutes between the AMSR-2 observations and the ground raingauge measurements. A new linearly-combined rainfall retrieval algorithm focused on heavy rain for the PCT and SI was validated using ground-based rainfall observations for the South Korea from 1 July - 30 August, 2016. The validation presented PCT and SI methods showed slightly improved results for rainfall > 5 mm h^-1 compared to the current ASMR-2 level 2 data. The best bias and root mean square error (RMSE) for the PCT method at AMSR-2 36.5 GHz were 2.09 mm h^-1 and 7.29 mm h^-1, respectively, while the current official AMSR-2 rainfall rates show a larger bias and RMSE (4.80 mm h^-1 and 9.35 mm h^-1, respectively). This study provides a scatteringbased over-land rainfall retrieval algorithm for South Korea affected by stationary front rain and typhoons with the advantages of the previous PCT and SI methods to be applied to a variety of spaceborne passive microwave radiometers.     

形状复杂的建筑物雷击截收面积的模型和计算方法

分析了雷电灾害风险评估中"截收面积"计算公式的单一性和局限性,将目前常见的形状复杂的建筑物划分为三大类(即"有一制高点的矩形建筑物、裙楼建筑物和L形建筑物")并形成模型。依据《建筑物电子信息系统防雷技术规范》GB50343—2012,通过"Auto CAD"画图软件画出相应模型的截收面积图,归纳得到对应模型截收面积的计算公式。经过实例对比,发现较经验法获取的形状复杂建筑物的截收面积更为精确,为雷电灾害风险评估中截收面积的快捷计算提供科学参考。     

洞穴滴水地球化学的空间和时间变化及其控制因素--以北京石花洞为例

通过对北京石花洞滴水地球化学一个水文年的观测,揭示了洞穴滴水水文地球化学季节变化与外界气候变化的关系,3个滴水点的滴率随降雨量的增加都有明显的变化,但不同滴水点滞后时间不同。滴水滴率、Mg²⁺和SO^{2-₄含量的季节变化数据显示,雨季洞穴滴水主要来源于当季降水,但也存在岩层滞留水的混入。滴水中Mg/Ca比值存在明显季节变化,旱季较低而雨季较高,但在雨季初期出现较大的波动。分析洞穴上覆土壤和洞内裂隙土壤数据,认为雨季初期滴水中Mg/Ca比值的波动是由土壤中Mg2+的快速淋溶造成的,上覆土壤结构性质和组分变化均影响滴水地球化学特征。}     

A calculation method for deformation of diaphragm wall of narrow deep foundation pit in soft soil considering spatio-temporal effectEI北大核心

为准确评估软土地区基坑施工安全以及对周围环境的影响,开挖过程中的时间和空间影响因素不可忽视。以长江漫滩软土地区某深基坑开挖工程为依托,首先建立考虑顺逆结合施工过程的有限元模型,将地连墙水平位移的计算值与实测值进行对比,验证有限元计算的可靠性;基于理论分析、数值计算和实测数据,采用坑角效应影响系数和等效水平抗力系数来衡量时空效应对支护变形的影响,提出考虑时空效应的地连墙变形计算方法;通过工程实例验证了在软土地区基坑设计计算中考虑时空效应的必要性以及所提计算方法的合理性。该研究成果可为软土地区深基坑变形计算提供有益借鉴。