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91.
The cause of the sinking of Henry VIII's Vice Flagship, the Mary Rose, as she sailed out to meet the French fleet on 19th July AD 1545, has remained an enduring mystery and contested encounter between the English and French Navies. The French claim was that the ship was holed by French cannon fire, whilst the English maintained that she sank due to a poorly executed navigational manoeuvre during the engagement. On the day of the sinking there was a total listed crew complement of 415 men onboard. Minimum number analysis of the commingled human assemblage identified only 179, from which we sampled 18 individuals from differing decks within the ship. We measured δ13C and δ15N in bone collagen, and δ18O and δ13C in enamel apatite of these individuals in order to obtain information about their diets and origins. While the collagen δ13C and δ15N data are similar to other medieval populations, the δ18O data indicate that a significant proportion of the crew did not originate in Britain, but rather they emanated from warmer, more southerly, regions. These data suggest the presence of 33–60% of non-natives, possibly mercenaries and/or ‘prest’ men, amongst the crew. Together with the contemporary remark shouted from the Mary Rose to a passing ship, that the Captain had the “type of knaves of whom, he could not rule”, our results lend weight to the suggestion that poor communication may well have contributed the observed fatal navigational manoeuvre which led to her sinking. 相似文献
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高校图书馆重点学科数据库建构 总被引:1,自引:0,他引:1
重点学科数据库建构对高校发展起着重要作用。文章论述了高校图书馆建设重点学科数据库的必要性,并对重点学科数据库的建设进行了初步探索。 相似文献
94.
以街道办事处为研究单元(以下简称街道),选取西安市主城区53个街道作为研究区域,利用Erdas imagine空间分类和建模方法、Arcgis区域分析方法、SPSS因子分析和聚类分析法等对2013年西安市主城区客观生活质量进行评价,并探究其空间格局。结果表明:①在生态环境因素主导下,外围客观生活质量高于接近内城的区域,南北区域高于东西区域,并在总体布局中出现"飞地";②在社会经济因素主导下,客观生活质量以内城为中心向四周辐射,形成放射状格局,同时在曲江等街道出现"异值区";③总体客观生活质量以内城及其南部区域较高,高值区呈现集中连片分布,低值区呈现"马鞍形"分布格局。 相似文献
95.
Sand injectites and related features that are interpreted to have formed by large‐scale, often sudden, fluid escape in the shallow (typically <500 m) crust are readily imaged on modern seismic data. Many of the features have geometrical similarity to igneous dykes and sills and cross‐cut the depositional stratigraphy. Sand injectites may be multiphase and form connected, high‐permeability networks that transect kilometre‐scale intervals of otherwise fine‐grained, low‐permeability strata. North Sea examples often form significant hydrocarbon reservoirs and typically contain degraded, low‐gravity crude oil. Fluid inclusion and stable isotope data from cements in sand injectites record a mixing of aqueous fluids of deep and shallow origin. 相似文献
96.
It is now common practice, by users of geographic information, to link data held at the postcode level to that obtained from the national census. This paper examines the relationship between Australia Post (AP) postcodes and Australian Bureau of Statistics (ABS) derived postal areas — which are an approximation of the former based on aggregated census collection districts (CDs). A group of adjacent ABS postal areas in northwest Melbourne was compared with the true AP postcode areas they purported to represent and the discrepancies were investigated. Firstly, shape mismatches were studied and their potential impacts upon resource allocation decisions were assessed. Next, comparisons of areas were undertaken. It was found that, in established inner city urban areas, the two sets of boundaries were highly correlated. However, outer suburban neighborhoods were identified as being particularly prone to major areal discrepancies. The implications of mismatches between these two key boundary data sources may be severe, given that management decisions and the allocation of public and private resources are often based on spatial statistical analyses which use these data sets. The authors acknowledge ABS efforts in providing information at the levels of aggregation that society demands. The introduction of ABS postal areas data has undoubtedly facilitated the use of demographic data in many sectors; it has, however, also caused some problems, for instance, when users assume that ABS postal areas are identical to AP postcodes. These issues could easily be avoided with the inclusion of more comprehensive metadata documentation accompanying ABS data. Research is continuing to develop a method by which agencies may derive common boundaries for their administrative units, yet still meet their own individual data and sampling requirements. 相似文献
97.
Many institutions and agencies are currently faced with the issue of geographic information systems‐enabling legacy databases. The problems can be acute for data sets that have been compiled through many years, using different standards and levels of recording. To explore these issues further, we report on a data quality assessment undertaken in 2002 for a subset of the archaeological site database of the province of Alberta, Canada. Our work shows that positional ambiguities in the data set can be highlighted and corrected by relatively straightforward procedures. This case study also provides an indication of the amount of work effort that will be involved in validating or ‘cleaning up’ data sets so model results and analyses undertaken with them are more reliable. 相似文献
98.
Scales of regional income disparities in the USA, 1955 2003 总被引:3,自引:0,他引:3
This article examines multiple dimensions of regional per capitaincome disparities in the USA between 1955 and 2003 with a particularfocus on scalar effects. It combines various exploratory analyticaltools of spatial disparities, including inequality indices,mobility indices, kernel density estimation, spatial autocorrelationstatistics and scale variances, to analyse regional averageper capita income distributions at multiple spatial scales,ranging from counties to multi-state regions. The analysis revealspreviously unrecognised systematic patterns of cross-scalardynamics, whereby spatial income disparities are increasinglymore pronounced at smaller scales in the last few decades. 相似文献
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为了解阿尔寨石窟壁画的制作工艺和颜料成分,采用偏光显微镜分析、剖面分析,并结合X射线衍射分析对6个洞窟的23个样品进行了分析。为了进一步研究阿尔寨石窟壁画颜料,还通过偏光显微法对其他地区和年代的壁画颜料进行了对比研究。结果表明,其绘制方法是先用加有麦秸的粘土将洞窟壁面抹平,然后用石灰涂白。再施以彩绘。所使用的颜料为矿物质颜料,多为绿、白、红、蓝色等。其绿色颜料为氯铜矿,白色颜料为碳酸钙,红色颜料为朱砂和铅丹,蓝色颜料为石青。 相似文献