Time series data correction for the Chang'E-1 gamma-ray spectrometer

The main goal of the gamma-ray spectrometer(GRS) onboard Chang'E1(CE-1) is to acquire global maps of elemental abundances and their distributions on the moon,since such maps will significantly improve our understanding of lunar formation and evolution.To derive the elemental maps and enable research on lunar formation and evolution,raw data that are received directly from the spacecraft must be converted into time series corrected gamma-ray spectra.The data correction procedures for the CE-1 GRS time series...     

空间科学虚拟观测台体系结构研究

科学观测数据的海量增长,使得旨在实现资源互操作的虚拟观测台(VO)应运而生,并迅速受到相关学科的支持和重视。国际虚拟天文台联盟(IVOA)、行星科学数据系统(PDS)和空间物理归档检索抽取标准(SPASE)等数据组织,正加快制定数据管理模型,推动VO的发展和跨学科应用。结合空间科学应用研究的特点,在借鉴国内外天文和空间科学VO研究成果的基础上,提出了一种针对空间科学数据的Hybrid型VO体系结构,并基于此体系结构发展了一个支持同步收割、格式化管道和事件关联发现的空间科学VO原型。实践和应用结果表明,基于这种体系结构建立的VO在解决全局资源的实时同步、异构应用的高度集成和面向科学问题的数据发现等问题上,有一定的普适性。     

江苏盐城原生盐沼湿地大型底栖动物重金属含量及生物质量评价

以江苏盐城国家级自然保护区核心区为研究区域,分别于盐蒿滩、互花米草滩、光滩采集大型底栖动物沙蚕、泥螺和四角蛤蜊样品,测定其体内重金属Hg,As,Cd,Cr,Cu,Pb,Zn和Ni含量,并运用统计分析、金属污染指数(MPI)、单因子污染指数(Pi)、生物-沉积物累积因子(BSAF)进行分析.结果表明,重金属元素在各类底栖动物体内的含量分布不同,Cd在光滩四角蛤蜊中富集最多,Zn在互花米草滩沙蚕中富集最多,Hg,As,Cr,Cu,Pb和Ni均在光滩泥螺体内富集最多.盐蒿沙蚕、米草沙蚕、光滩泥螺和光滩蛤蜊MPI值分别为1.984,2.085,4.320和1.618.泥螺受污染程度最重,超出沙蚕和四角蛤蜊的2倍.沙蚕、四角蛤蜊体内Zn的积累量、泥螺体内As和Cu的积累量均高于沉积物.按照海洋贝类生物质量标准中的第一类指标对样品进行生物质量评价,发现研究区泥螺体内Cr,Cu和Pb含量均超过此标准,尤以Pb超标最为严重,污染指数Pi值达7.628.四角蛤蜊生物质量总体良好,除Cd和Cr超标,分别为海洋贝类质量标准的1.812倍和1.408倍外,其余元素均未超过标准.方差分析显示不同大型底栖动物种类对重金属的富集能力差别较大.生物类型比环境背景对重金属在生物体内的富集影响更大.研究区泥螺和四角蛤蜊体内的多数重金属元素含量低于国内其他区域的同种底栖动物.     

河海交互作用与黄东海域古扬子大三角洲体系研究

河海交互作用与堆积型大陆架发育,是中国海浅海地貌的主要特色.发源于世界屋脊的大河中有5条汇入中国海,源远流长,携运了巨量泥沙被阻积于岛弧背侧的边缘海中.经过漫长的新生代地质时期,尤其是在中、晚更新世堆积为陆架,并经历着全新世海侵过程中的浪流改造.作者通过近30年对区域海岸海洋研究的成果积累,逐渐认识到:在南黄海-东海海域,分布着一个巨型的三角洲体系:基底的大三角洲是中、晚更新世由古长江、古黄河两条世界级大河输水供沙,受季风波浪和潮流作用形成的,其发育时代应在长江贯通下游汇入黄、东海以后;其上叠置发育了规模逐次减小的古江河三角洲、南黄海辐射沙脊群、全新世—现代长江三角洲和历史时期的废黄河三角洲,组成巨型的复合三角洲体系,表层经全新世以来海侵改造发育了波浪与潮流共同作用的沙脊地貌.大三角洲体系覆盖着东海及南黄海海底,形成大陆架表层沉积地貌.这一巨型的河-海交互作用大陆架、三角洲体系,独具特色,具有重大的研究价值.建议:首先需进行一体化全方位的多项调查,包括遥感影像判识,水深与地震剖面探测,海底底质与钻孔取样,以及现代水文泥沙测量等,阐明其分布与环境特征;再进一步开展多学科交叉研究——地质地理、地貌、沉积、海洋动力、海平面变化与河流变迁、海洋地理信息系统等,期以阐明古扬子大三角洲体系各组成部分分布的范围、沉积组成和地貌特点,以及相互叠置关系.最终期以揭示中、晚更新世以来河-海交互作用过程与动力机制、海岸变迁与陆架堆积发育等基础科学问题,为亚太边缘海与大河相互作用的堆积型陆架发育提供实证,丰富海洋地质学理论.同时,可阐明现代海岸滩涂的蚀、淤动态,为新生土地资源规划利用,物源及陆架海疆权益维护提供重要的科学依据.     

A macroscopic model for predicting the relative hydraulic permeability of unsaturated soils

A macroscopic model for predicting the relative hydraulic permeability of unsaturated soils is proposed. In this model, pores in unsaturated soils are considered to be parallel flow tubes. The water flow in the pores is assumed to take place in the water film on the inside wall of the flow tubes. The viscosity of pore water is considered to be different from the viscosity of pure water and variable with the variation of degree of saturation. The values of tortuosity factor and pore shape factor of unsaturated soils are estimated theoretically. The theoretical model is verified using experimental data for 32 different soils. For application in engineering practice, the value of viscosity of pore water in different soils is proposed.     

Hydrochemical and hydrological processes in the different landscape zones of alpine cold region in China

Investigation of water sources and flow pathways is crucial to understand and evaluate the characteristics of surface water and groundwater systems. This article aims to identify the hydrochemical and hydrological processes in different landscape zones based on hydrochemical analyses of various samples, including samples from glacier, snow, frozen soil meltwater, surface water, groundwater, and precipitation, in the alpine cold region of China. Hydrochemical tracers indicated that chemical compositions are characterized by the Ca-HCO₃ type in the glacier-snow zone; the Mg-Ca-SO₄ type in the alpine cold desert zone; the Ca-HCO₃-SO₄ type in the marsh meadow zone; the Ca-Mg-HCO₃ type in the alpine shrub zone; and the Ca-Na-SO₄ type in the mountain grassland zone. An end-member mixing model was used for hydrograph separation. The results showed that the Mafengou River in the wet season was recharged by groundwater in the alpine cold desert and alpine shrub zones (67%), surface runoff in the glacier-snow zone (11%), surface runoff in the alpine cold desert zone (8%), thawed water from frozen soil in the marsh meadow and mountain grassland zones (9%), and direct precipitation on the river channel (5%). This study suggests that precipitation from the whole catchment yielded little direct surface runoff; precipitation was mostly transformed into groundwater or interflow and was then concentrated into the river channel. This study provides a scientific basis for evaluation and management of water resources in the basin.     

甘孜－理塘板块缝合带研究的新进展

本文首次将甘孜－理塘板块缝合带划分为韧性剪切带及断层构造系统、古生代构造推覆体、蛇绿岩构造组合体。被动陆缘复理石建造、活动陆缘弧前沉积建造、与板块俯冲碰撞有关的花岗岩体、断陷沉积盆地和第三纪推覆构造带等边界地质体。它们形成演化与甘孜－理塘洋壳的俯冲、弧－陆碰撞、陆内会聚、断陷和平移走滑等构造活动密切相关。     

Weighted fuzzy kernel-clustering algorithm with adaptive differential evolution and its application on flood classification

Flood classification is the fundamental problem of flood risk analysis and plays an important role in flood disaster risk management. Considering the fact that flood classification is a problem of multi-attribute and multi-stage fuzzy synthetically evaluation, this paper mainly proposed the weighted fuzzy kernel-clustering algorithm (WFKCA) with adaptive differential evolution algorithm (ADE) to solve this problem. Firstly, WFKCA is detailed introduced, and then the differential evolution algorithm (DE) is applied for the fuzzy clustering, thus to obtain the better results. Taking into consideration the disadvantage of DE, ADE is present after the introduction of DE. Finally, the combination of WFKCA and ADE is applied for flood classification, and the results demonstrated the methodology is reasonable and reliable, thus provide a new effective approach for flood classification.     

2013年4月20日四川芦山MW6.7 (MS7.0)地震参数的测定

2013年4月20日四川芦山M_W6.7(M_S7.0)地震发生后, 中国地震台网中心(CENC)发布了地震速报参数. 该文利用中国国家地震台网97个台站的资料对地震速报参数进行了修订, 得出: 四川芦山M_W6.7地震的发震时刻为北京时间8时2分47.5秒(世界时间0时2分47.5秒), 震中位置为30.30°N、 102.99°E, 震源深度17 km. 该地震的面波震级为M_S7.0, 短周期体波震级为m_b6.0, 中长周期体波震级为m_B7.0; 利用波形反演的方法计算了震源机制解, 得到的最佳双力偶解的参数分别为节面Ⅰ: 走向17°/倾角48°/滑动角80°; 节面Ⅱ: 走向212°/倾角43°/滑动角101°, 矩震级为M_W6.7. 中国地震台网中心发布本次地震为面波震级M_S7.0, 而美国地质调查局(USGS)国家地震信息中心(NEIC)发布为矩震级M_W6.6. 为了消除这种差别, 建议我国也应将矩震级作为对外发布的首选震级, 使震级的发布与国际接轨.      

Design of conceptual model in digital map database

The components of map information are analyzed theoretically in this paper, and the map information includes mainly the spatial information, at tributive information and temporal characteristics information. Then the digital map entity is defined according to construction characteristics of the map information. Finally, on the basis of the analyses of the construction characteristics of digital map entity and present conceptual model of digital map database, an abstracted conceptual model of digital map database is presented. And the Normal Form theory of relational database is discussed particularly.