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E. Cornelissen A. Boven A. Dabi J. Hus K. Ju Yong E. Keppens R. Langohr J. Moeyersons P. Pasteels M. Pieters H. Uytterschaut F. Van Noten H. Workineh 《African Archaeological Review》1990,8(1):23-75
This contribution reports on the results obtained from the 1980–7 research in the Kapthurin Formation (Baringo, Kenya) which aimed at the refinement of the chronology, stratigraphy and environmental evidence in order to establish a framework for the interpretation of the prehistoric sites. In 1966 a Late Acheulean industry with prepared-core technique and blade component, dated betweenca 0.82/0.64 myr and 0.23 myr had been described in the area concerned. All the sites belong to the middle Kapthurin formation which is situated in the Bruhnes normal polarity chron and has a lower limit of 0.58 myr. The upper limit of 0.23 myr could not be confirmed. The fauna is consistent with the available dating evidence. The sites are situated in a flat savanna landscape which was built up by a braided river system under slightly more humid conditions than the present climate. On some of the sites artifacts were found in association with palaeosoils. Although the interpretation of such assemblages must consider the impact of natural turbation processes, the palaeosoils provide exceptional conditions for comparing sites from the same phase of landscape stabilization. The present archaeological evidence suggests a sequence of Late Acheulean and Post-Acheulean (Sangoan?, Middle Stone Age) assemblages rather than the presence of one single industry as described previously. The relation between these assemblages and the two mandibles ofHomo sp. (aff.erectus) BK67 and BK8518 (found in 1966 and 1982) emphasizes the need for more research in the area. 相似文献
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王菊 《文物保护与考古科学》2017,29(3):91-96
甘肃省博物馆藏唐代\"红地团窠对鸟纹锦\",存在残缺、污染、糟朽等严重病害,急需进行保护修复。本工作在采用测色仪、便携式荧光光谱仪、数码相机、掌上便携式显微镜scalar等专业仪器对该纺织品文物进行无损分析检测。依据检测结果和纺织品保存现状制定了科学的保护修复方案,继而采用支撑法,选用风格相近的背衬面料进行缝合加固,并对修复难点等问题进行研究分析。修复后的织锦纹理清晰,丝线稳固,色泽协调,整体牢固度提高,达到了理想的保护修复效果。此成果对今后同类文物的保护修复具有借鉴意义。 相似文献
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谷水与洛阳诸城址的关系初探 总被引：1，自引：0，他引：1
洛阳盆地群山环抱,地势险要。境内河流纵横,大的有伊、洛、、涧(谷水)四条,以它们为主干形成了密如蛛网的水道。洛阳诸水,以洛河最长,但谷水与洛阳的文化及城址变迁的关系也十分密切。目前关于谷水的研究还十分欠缺,一些学者的认识也不系统,多是先揣测地望再进行推论,结论缺乏考古学 相似文献
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文溯阁《四库全书》自送往入藏时即已有撤改之举,直至嘉庆十二年补函工作结束才最终成帙。整个撤改书籍的过程非常繁复,学界研究关注多集中在文溯阁书的两次复校,而对不同时期的撤改着墨较少,特别是复校开始前和嘉庆八年续缮书籍之前对阁书的抽换,这是文溯阁书得以完帙的关键。同时,阁书的撤改直接导致某些书籍的进呈本与阁本内容相异,甚至各阁本之间亦有不同。因此,追溯各阁书籍异同时,切不可一味认定是底本撤换而致。 相似文献
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武威磨嘴子汉墓出土\"印花绢袋\",现藏于甘肃省博物馆。因存在残缺、污染、糟朽等严重病害,急需进行保护修复。本工作在参照修复方案中相关专业仪器检测分析结果的基础上,查阅文献,寻找线索,研究推断出了绢袋形制。采用支撑法,选用风格相近的现代面料作为背衬,表面应用绉丝纱加固技术,对绢袋实施了保护修复,并对关键环节的技术要点作了总结归纳。修复后的绢袋形制明确,纹理清晰,光泽协调,整体牢固度提高,观展效果增强,达到了理想的保护修复效果,对今后同类文物的保护修复具有借鉴意义。 相似文献
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Ju Zhang 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):434-449
Ordovician graptolite-bearing strata in eastern Yunnan were deposited in nearshore, shallow-water environments. Graptolites are systematically described from three sections through the Hungshihyen Formation in eastern Yunnan Province, China: (1) Hongshiya section near Ercun village, Kunming; (2) Liujiang section, Luquan; and (3) Guihuaqing Reservoir section, Luquan. The graptolite fauna, characterized by the predominance of deflexed forms, includes ten species in two genera: Baltograptus turgidus (Lee), B. varicosus (Wang), B. yunnanensis (Li), B. calidus (Ni), B. enshiensis (Ni), Baltograptus sp. cf. B. deflexus (Elles & Wood), Baltograptus sp. cf. B. bolivianus (Finney & Branisa), Baltograptus sp. A, Baltograptus sp. B and Corymbograptus v-fractus minor (Li). A detailed morphological study of these southern Chinese graptolite faunas suggests that Baltograptus wudingensis (Li) is a junior synonym of B. turgidus (Lee); Baltograptus kunmingensis (Ni) is a junior synonym of B. varicosus (Wang); and Baltograptus triangulatus (Ni) is a junior synonym of B. yunnanensis (Li). The B. varicosus Biozone is newly recognized within the middle part of the Hungshihyen Formation, replacing the former Didymograptus deflexus Biozone. This interval is well correlated to the Baltograptus jacksoni Biozone in Britain, the Tetragraptus akzharensis, ‘Baltograptus cf. deflexus’ and Didymograptus bifidus (lower part) biozones in NW Argentina (eastern Cordillera), and the Acrograptus filiformis and Didymograptellus eobifidus biozones in northern Guizhou, South China. Accordingly, the interval is of mid-Floian age, rather than late Floian as previously proposed. 相似文献
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Vivian Yi‐Ju Chen Wen‐Shuenn Deng Tse‐Chuan Yang Stephen A. Matthews 《Geographical analysis》2012,44(2):134-150
In recent years, techniques have been developed to explore spatial nonstationarity and to model the entire distribution of a regressand. The former is mainly addressed by geographically weighted regression (GWR), and the latter by quantile regression (QR). However, little attention has been paid to combining these analytical techniques. The goal of this article is to fill this gap by introducing geographically weighted quantile regression (GWQR). This study briefly reviews GWR and QR, respectively, and then outlines their synergy and a new approach, GWQR. The estimations of GWQR parameters and their standard errors, the cross‐validation bandwidth selection criterion, and the nonstationarity test are discussed. We apply GWQR to U.S. county data as an example, with mortality as the dependent variable and five social determinants as explanatory covariates. Maps summarize analytic results at the 5, 25, 50, 75, and 95 percentiles. We found that the associations between mortality and determinants vary not only spatially, but also simultaneously across the distribution of mortality. These new findings provide insights into the mortality literature, and are relevant to public policy and health promotion. Our GWQR approach bridges two important statistical approaches, and facilitates spatial quantile‐based statistical analyses. En los últimos años se han desarrollado diversas técnicas para explorar tanto la heterocedasticidad (o no estacionariedad) espacial, así como para modelar toda la distribución de una variable dependiente. El primer tema ha sido abordado principalmente por la regresión ponderada geográficamente (Geographically Weighted Regression ‐GWR), y el segundo por la regresión por cuantiles (Quantile Regression‐QR). La combinación de ambas técnicas analíticas, sin embargo, ha recibido mucho menos atención. El objetivo de este artículo es llenar dicho vacío mediante la propuesta de una regresión geográficamente ponderada por cuantiles (Geographically Weighted Quantile Regression‐ GWQR). Los autores resumen brevemente las técnicas GWR y QR respectivamente, y luego esbozan sus propiedades sinérgicas. Luego presentan la nueva técnica propuesta: GWQR. Los autores abordan los temas de las estimaciones de los parámetros GWQR y sus errores estándar, el criterio de selección del ancho de banda de la validación cruzada (cross‐validation bandwidth), y la prueba heterocedasticidad espacial. Como ejemplo se aplica GWQR a datos de la tasa de mortalidad como variable dependiente y cinco determinantes sociales como variables independientes para los condados de los Estados Unidos. Los patrones espaciales se presentan en mapas con los resultados del análisis para los percentiles 5, 25, 50, 75, y 95. Los resultados muestran que las asociaciones entre la mortalidad y sus factores determinantes no sólo varían espacialmente, sino también de forma simultánea a través de la distribución de la tasa de mortalidad. Estos nuevos hallazgos coinciden con la literatura de los estudios de mortalidad, y son relevantes para aplicaciones de política pública y promoción de la salud. El enfoque GWQR representa un puente conceptual y metodológico entre dos enfoques estadísticos importantes a la vez que hace más factible el análisis estadístico espacial por cuantiles. 近年来,可用于探讨空间非平稳性和模拟回归变数分布的技术得到发展。前者主要用地理加权回归方法（GWR）处理,后者采用分位数回归（QR）处理。然而对这些分析技术的结合使用却很少关注。本文试图通过提出地理加权分位数回归（GWQR）来填补这一空白。在分别简要回顾了GWR和QR方法的基础上,基于两个方法的协同应用提出了GWQR新方法,进而讨论了GWQR的参数估计、标准误差、带宽选择标准的交叉验证和非平稳性检验。本文将死亡率作为因变量及五个社会因子作为解释变量,进行了美国县域单元的案例研究,绘制了0.05、0.25、0.5、0.75和0.95不同百分位点的分析结果图。研究发现,死亡人数不仅与解释变量的空间分布相关,同时也与其地理分布相关。这些新发现不仅可促进对死亡率相关成果的深入分析,同时也与公共政策和健康促进有关。GWQR方法架构了QR和GWR两种重要统计方法之间的纽带,也促进了基于分位数的空间统计分析方法的发展。 相似文献
28.
防水材料在木材保护中的尝试 总被引：2，自引：1，他引：1
防水材料是在室外岩土文物保护中广泛使用的一种材料.为了解常用防水材料应用于木材上的效果,使用全自动测色色差仪、接触角测定仪等对防水材料处理前后木材各项性能的变化进行了测定分析,包括颜色变化、接触角变化、毛细吸水、全浸吸水、霉菌实验、防水剂分布和对后续保护的影响.实验表明,各种防水材料处理后的木材都有一定的防水效果.其中,高浓度WD-10在各方面表现优良.在长期的潮湿环境下,木材仍然滋生霉菌,因此需要同时考虑使用防霉防腐剂和其他保护材料.防水材料的使用不会影响到后续保护工作. 相似文献
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关于日本在华北的劳务统制若干问题研究 总被引：1，自引：0，他引：1
华北当年曾是日本掠夺中国强制劳工的主要来源地,因此研究与揭露日本在华北的劳务掠夺统制内幕是彻底调查日本使用中国强制劳工暴行的重要环节。现据天津市档案馆和中国第二历史档案馆有关档案文献,以及当年日本在华北经济调查机关出版的有关调查报告等史料,对日本在华北劳务统制掠夺中的若干问题研究披露如下,供国内外学者深入研究参考。一、华北是日本掠夺中国强制劳工的主要源地这个问题,本人在《日本强掳华北劳工人数考》（载《抗日战争研究》１９９５年４期）和《日本在华北经济统制掠夺史》（天津古籍出版社１９９７年６月版）中… 相似文献