Modelling spatial heterogeneity and anisotropy: child anaemia,sanitation and basic infrastructure in sub-Saharan Africa

Public interventions in support of public health and housing in developing countries could benefit from better understanding of spatial heterogeneity and anisotropy. Estimation of directional variation within geographically weighted regression (GWR) faces problems of local parameter instability, border effects and, if extended to non- spatial attributes, potential endogeneity. This study formulates a GWR model where anisotropy is filtered out based on information from directional variograms. Along with classical regressions, the approach is applied to investigate child anaemia and its associations with household characteristics, sanitation and basic infrastructure in 173 regions of sub-Saharan Africa. Based on ordinary least squares (OLS) results, anaemia prevalence rates are up to three times more responsive to child morbidity (related to malaria and other diseases) than to other covariates. GWR estimates provide similar indications, but also point to poor sanitation facilities as a cofactor of severe anaemia particularly in east and southern Africa. The anisotropy-adjusted GWR is spatially stationary in residuals, and its estimated local parameters are less collinear than GWR with no adjustment. However, similar explanatory power and lack of significant bias in parameters estimated by the latter suggest that directional variation is largely captured by modelled co-movements among the variables.     

对《长螺旋钻孔泵压混凝土桩复合地基技术规程》有关问题的讨论

河北省《长螺旋钻孔泵压混凝土复合地基技术规程》(2011版)实施一年以来,一些技术人员对于规范中如素混凝土桩布桩原则、褥垫层厚度的取值、单桩承载力特征值的取值、土层压缩模量取值等提出不同的见解和疑问,据此,根据规程一些条款和相关技术资料,提出看法和见解,以期在实际工作中更更具有可操作性和更合理的应用。     

Uncertainties in the preparation of Ra Mn fiber standards

Delayed coincidence counters (RaDeCC), used for measuring ²²³Ra and ²²⁴Ra preconcentrated from water onto MnO₂-impregnated acrylic fiber (“Mn-fiber”), require a standard Mn-fiber column that has a precisely known activity of ²²⁴Ra for calibration. This may be done by adding an aged ²²⁸Th standard solution to adsorb both ²²⁸Th and its daughter ²²⁴Ra quantitatively onto a Mn fiber. We used both seawater and deionized water (DIW) for testing the adsorption efficiency of Th and Ra onto Mn fibers. Our experimental results show that more than 50% of thorium (²³²Th and ²²⁸Th) breaks through the Mn-fiber column when DIW is used as a medium. However, near quantitative recoveries are obtained if filtered (0.45 μm) seawater is used to prepare the standard. In the case of pure DIW, the pH (initial pH  5.3) rises to > 10 after passing through the column while seawater (initial pH  7.8) changes to  7.2. Thus, the lack of thorium adsorption in DIW may be attributed to this huge increase of pH and the consequent formation of Th(OH)₄ and polyhydroxyl colloids. Based on these observations, we recommend that one should use either artificial seawater or natural seawater (which has negligible ²²⁴Ra and ²²⁸Th) as a loading solution after 0.45 μm filtration. In addition, the thorium adsorption efficiency should be confirmed either by thorium analysis of the effluent solution or long-term monitoring of the supported ²²⁴Ra on the Mn fiber using the RaDeCC. Similar cautions are likely necessary for making ²²³Ra standards by adsorption of ²²⁷Ac onto Mn fibers.     

碳酸盐碳氧同位素标准物质性状对分析和保存的影响

碳酸盐物质碳氧同位素广泛应用于地质和气候环境研究,而标准物质是其分析的基准物质和数据比较的重要依据.不同标准物质性状存在差异,对于性状特点的了解,有助于标准的选择和使用、不均匀性的改善以及最佳实验条件的建立.本文采用X射线衍射(XRD)、光学显微镜及能谱扫描-电子显微镜(EDX-SEM)技术,从不同尺度对物源、粒径、颗...     

“数字东营”地理信息共享标准体系的建立与研究

"数字东营"是由中国信息产业部、科技部和建设部三部委联合打造的山东省东营市数字化城市建设项目。经过五六年的建设,目前信息化水平走在全国数字城市建设的前列。为了进一步推动数字东营建设步伐,实现数据共享,参照国内外关于地理信息共享标准与规范,着重参考了"数字山东"标准规范,同时结合东营的实际制定出一套具有东营市特点"数字东营"地理信息共享标准体系。该体系主要从空间基础框架、数据存储、技术指标、数据分类、数据组织结构进行标准化和规范化,具有很好推广与借鉴价值。     

A protocol standard for heterogeneous telescope networks

The scientific need for a standard protocol permitting the exchange of generic observing services is rapidly escalating as more observatories adopt service observing as a standard operating mode and as more remote or robotic telescopes are brought on‐line. To respond to this need, we present the results of the first interoperability workshop for Heterogeneous Telescope Networks (HTN) held in Exeter. We present a draft protocol, designed to be independent of the specific instrumentation and software that controls the remote and/or robotic telescopes, allowing these telescopes to appear to the user with a unified interface despite any underlying architectural differences. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Astronomical network event and observation notification

Networks are becoming a key element in most current and all future, telescope and observatory projects. The ability to easily and efficiently pass observation data, alert data and instrumentation requests between distributed systems could enable science as never before. However, any effective large scale or meta‐network of astronomical resources will require a common communication format or development resources will have to be continuously dedicated to creating interpreters. The necessary elements of any astronomy communication can be easily identified, efficiently described and rigidly formatted so that both robotic and human operations can use the same data. In this paper we will explore the current state of notification, what notification requirements are essential to create a successful standard and present a standard now under development by the International Virtual Observatory Alliance (IVOA), called the VOEvent. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

An RTML transport implementation on the Liverpool Telescope

The Liverpool Telescope is a 2.0m fully robotic telescope based on the Canary island of LaPalma. In this paper I describe the Java(TM) implementation of a method to transport RTML (Remote Telescope Markup Language) between a Node Agent (Web Services endpoint) embedded at the telescope and a remote Agent. The advantages and disadvantages of the method are discussed, along with the suitability of the protocol for HTN standardisation. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Robonet‐1.0

Robonet‐1.0 is a prototype network of 2m robotic telescopes spread out around the world, consisting of three 2 metre telescopes. In this paper we present some of the science done with the network and how we use eSTAR and HTN technologies to perform observing programmes in an efficient manner. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

大天区望远镜中sCMOS相机的测光精度分析

与传统CCD (Charge Coupled Device)相机相比, s COMS (scientific Complementary Metal Oxide Semiconductor)相机被广泛装备于超大天区巡天设备,与传统CCD相机不同的是sCMOS相机采用卷帘式快门,因此对其进行测光精度的分析工作是很有意义的.首先,将s CMOS相机拍摄的图像与UCAC2 (The Second U.S. Naval Observatory CCD Astrograph Catalog)星表进行匹对,识别图像中的UCAC2标准星.接着对图中的标准星进行测光并提取测光数据进行最小二乘直线拟合,获得了相应的系统转换系数并得到仪器星等至标准星等的转换公式.然后,将转化后的仪器星等和标准星等做差并计算相应的均方根误差.最后,利用计算得到的均方根误差评估sCMOS相机的测光精度,并将标准星按星等划分后,分析了相应的测光误差.计算结果表明在标准测光夜测量亮度亮于14等的星时,测光精度优于0.15 mag.通过实测精度分析可知卷帘快门sCOMS相机具有较高的测光精度,基本满足空间碎片巡天观测的要求.