Detecting subtle hydrochemical anomalies with multivariate statistics: an example from ‘homogeneous’ groundwaters in the Great Artesian Basin,Australia     

Bethany O'Shea  Jerzy Jankowski 《水文研究》2006,20(20):4317-4333

The major ion composition of Great Artesian Basin groundwater in the lower Namoi River valley is relatively homogeneous in chemical composition. Traditional graphical techniques have been combined with multivariate statistical methods to determine whether subtle differences in the chemical composition of these waters can be delineated. Hierarchical cluster analysis and principal components analysis were successful in delineating minor variations within the groundwaters of the study area that were not visually identified in the graphical techniques applied. Hydrochemical interpretation allowed geochemical processes to be identified in each statistically defined water type and illustrated how these groundwaters differ from one another. Three main geochemical processes were identified in the groundwaters: ion exchange, precipitation, and mixing between waters from different sources. Both statistical methods delineated an anomalous sample suspected of being influenced by magmatic CO₂ input. The use of statistical methods to complement traditional graphical techniques for waters appearing homogeneous is emphasized for all investigations of this type. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

大历十才子与方外隐逸诗人之隐逸诗比较     

张声怡 《广东海洋大学学报》2005,25(5):82-88

“吏隐”作为大历十才子的生活特征之一,也成为他们创作的题材,这与当时方外隐逸诗人因其不同的人生观照所创作的诗作相映成趣。方外隐逸诗人又可分为隐士诗人和诗僧两个群体,大历十才子和方外隐逸诗人之间体现出了完全不同的生命体验,方外隐逸诗人对真隐精神的写作与十才子的“伪隐”形成了鲜明的对比,就后者来说,现实的功利主义态度和价值上的物质取向使其隐逸诗作之精神内涵大打折扣。  相似文献   

互补的神话--鲁迅与张爱玲文学与人生观之比较     

朱红梅 《广东海洋大学学报》2002,22(5):58-63

鲁迅和张爱玲 ,创造了二十世纪中国文学的两个神话。对照各自的文学创作与人生观 ,两者有着颇含默契的互补意味。不同的文学视角与精神关怀赋予彼此人格我不同的深度与质感 ;乡镇意识与城市情结使得两者的文学创作风格各异却又相得益彰 ;迥异的文化背景与人生阅历造成了彼此截然不同的人生态度  相似文献   

NEW OBSERVATIONS ON THE MEIOTIC PROCESS IN THE MARINE DINOFLAGELLATE NOCTILUCA SCINTILIANS （NOCTILUCALES, DINOPHYCEAE）     

周成旭  严小军 《中国海洋湖沼学报》2002,20(1):67-73

The meiotic process in Noctiluca scintillans were observed under light microscope.Some abnormal cell divisions, incompletely separated “zoospores” and the changes of the zoospores are described in this paper. Together with the fmdings of field samplings and the previous results by other researchers, the process of meiosis in N. scintillans was supposed to be a pathway to reduce the extra high density of NH3-N within the cell in order to ensure normal population growth.  相似文献   

The trouble with nature: Ambivalence in the lives of urban Australian environmentalists   总被引：1，自引：0，他引：1  

Aidan Davison   《Geoforum》2008,39(3):1284-1295

The number and range of contests over the social production of nature is growing. Much environmentalist discourse, however, continues to appeal for unequivocal scientific support on clearly demarcated issues of pure, a-social nature. This paper explores the question of how participants in environmental movements view this demarcation in the context of their own lives. After introducing scholarly critique of dualistic ideas of nature and the ambivalence characteristic of environmentalist conceptions of nature, the paper draws upon a qualitative study with environmentalists in the Australian cities of Melbourne, Perth and Hobart. Inquiring into the interplay of discourse of nature and everyday worlds, interviews revealed a complex interdependence of dualistic and non-dualistic understandings of nature. This ecology of ideas was especially evident in spatial imaginaries of nature. Scientific terminology, social disaffection and pessimism were associated with abstract and mutually exclusive conceptions of society and nature. Reflections on personal experience, however, indicated more flexible and hopeful negotiations in everyday liminal spaces offering ‘the best of both worlds’. It is concluded that environmentalist resistance to dismantling of conceptual boundaries between society and nature may often stem not from failure to appreciate socionatural complexity, but from a strongly felt sense that the self can only truly be found in nature.  相似文献   

国家级自动气象站蓄电池智能控制检测系统设计     

于子敏  常奋华  杜言霞  张华琳  陈淼 《气象科技》2018,46(4):651-658

对国家级自动气象站供电系统深入研究,通过对蓄电池充放电进行细微控制,设计报警电路、寿命检测电路和远程监控上位机软件系统,实时监测蓄电池状态,对蓄电池长期处于浮充状态致使其寿命缩减的设计缺陷进行改进。该系统采用Freescale高性能处理器和以AD8210为核心的高边电流检测电路,实时对分流电阻的微电流进行检测,及时阻止危害蓄电池使用寿命的过充和过放,通过声光报警电路和数据通信电路将交流电断电报警、蓄电池电压、使用寿命和充电间隔等信息传送到Labview编写的上位机软件,提醒观测员及时处理,同时配合RTC时钟模块,每3个月自动对蓄电池进行充放电维护,不仅有效延长了蓄电池的使用寿命,还解决了蓄电池充放电维护问题,减少了国家站备份蓄电池每两年更换造成的资源浪费。  相似文献   

Rural Social Networks along Amazonian Rivers: Seeds,Labor and Soccer among Communities on the Napo River,Peru          下载免费PDF全文

Christian Abizaid  Oliver T. Coomes  Yoshito Takasaki  J. Pablo Arroyo‐Mora 《Geographical review》2018,108(1):92-119

Research on Amazonian communities has focussed more often on rural‐urban linkages than on links among rural communities. This is unsurprising, given the low density of population, limited intercommunity commerce, and importance of direct city‐market relations. Social relations among rural communities are also important in shaping rural livelihoods and lifeways. We report on the findings of a large‐scale census of communities in the Napo River basin in northeastern Peru (n=174). Data were gathered on intervillage crop seed acquisition and cooperative labor sharing as two key inputs in agriculture, and on intervillage soccer matches, which are integral to rural social life. We analyze the socio‐spatial networks of each practice, paying attention to settlement patterns, community ethnicity, and differential access to the uplands. We find that seeds and labor flow along soccer network lines. Rural social networks appear to be structured strongly by ethnicity (homophily) and reflect important complementarities between upland and lowland communities (weak ties).  相似文献   

Applying VGI to collaborative research in the humanities: the case of ARTL@S     

Catherine Dossin  Nicole Ningning Kong 《制图学和地理信息科学》2017,44(6):521-538

ABSTRACT

Using Artl@s as an example of a project that relies on volunteered geographic information (VGI), this article examines the specific challenges that exist, beyond those frequently discussed in general VGI systems (e.g., participants’ motivation and data quality control) in regard to sharing research data in humanities: (1) most data from the humanities is qualitative and collected from multiple data sources which are often inconsistent and unmappable; (2) data is usually interconnected with multiple relationships among different tables which creates challenges for both mapping and query functionality; (3) data is both geographical and historical. Consequently addresses that no longer exist have to be geolocated and visualized on historical basemaps and spaces must be represented diachronically; (4) the design of web map application needs to balance both sophisticated research requirements and a user-friendly interface; (5) finally contributors expect their data to be cited or acknowledged when used in other studies and users need metadata and citation information in order to reuse and repurpose datasets.

In this article, we discuss how Artl@s, a project which developed a georeferenced historical database of exhibition catalogues, addresses these challenges. Artl@s provides a case study for VGI adoption by digital humanities scholars for research data sharing, as it offers features, such as flexible batch data contribution, interrelated spatial query, automatic geolocalization of historical addresses, and data citation mechanisms.  相似文献   

通勤时间、社区活动对社区社会资本的影响：基于北京26个社区的调查研究   总被引：1，自引：0，他引：1  

李春江  张艳  刘志林  柴彦威 《地理科学》2021,41(9):1606-1614

城市扩张和郊区化显著增加居民的通勤时间,减少居民在社区内及周边开展的日常活动,进而可能对居民的社区社会资本产生消极影响。基于2017年北京市26个社区居民的社区融合与活动日志问卷调查数据,通过构建结构方程模型,探讨通勤时间、社区活动对社区社会资本的影响机制。结果发现,控制居民社会经济属性和社区区位后,长时间通勤会减少居民在社区及周边1 000 m范围内开展的活动,并进一步对社区社交网络结构、社会信任和共同价值等社区社会资本的不同维度产生负面影响。此外,社区活动中社交娱乐活动的中介效应显著,而个人和家庭事务活动中介效应不显著。最后,证实了促进职住平衡、减少职住分离的规划政策对于增加居民社区活动及培育社区社会资本的重要意义。  相似文献   

高质量发展目标下黄河流域城市居民生活质量的时空格局及障碍因子   总被引：2，自引：1，他引：1  

赵宏波  岳丽  刘雅馨  董冠鹏  苗长虹 《地理科学》2021,41(8):1303-1313

提高居民生活质量是实现黄河流域高质量发展的重要目标和具体体现。从居民生活、基础设施、公共服务、生态环境4个方面构建城市居民生活质量评价指标体系,测度2004―2018年黄河流域城市居民生活质量水平,利用核密度估计、ESDA、Dagum基尼系数等方法进行居民生活质量时空格局分析及空间差异测度,并运用障碍因子诊断模型分析影响居民生活质量水平的障碍因子,得出如下结论：① 2004―2018年黄河流域城市居民生活质量高水平区域从下游城市逐渐转移到中上游城市;② 黄河流域城市居民生活质量高?高集聚区主要是内蒙古自治区及相邻区域的城市,低?低集聚区主要是河南省、山东省以及山西省的部分城市;③ 黄河流域城市居民生活质量水平的空间差异从上中下游尺度看主要是区域间净值差异贡献,从左右岸尺度看主要是区域内部差异贡献;④ 黄河流域城市居民生活质量水平的障碍因子主要是人均水资源量、移动电话年末用户数、每万人公园绿地面积、教育支出占财政支出比重、每万人拥有的道路面积与人均可支配收入等,因此在未来的高质量发展中要注重生态环境保护,特别是合理利用水资源,完善城市基础设施与提升公共服务水平。  相似文献