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31.
GIScience and GISystems have been successful in tackling many geographical problems over the last 30 years. But technologies and associated theory can become limiting if they end up defining how we see the world and what we believe are worthy and tractable research problems. This paper explores some of the limitations currently impacting GISystems and GIScience from the perspective of technology and community, contrasting GIScience with other informatics communities and their practices. It explores several themes: (i) GIScience and the informatics revolution; (ii) the lack of a community‐owned innovation platform for GIScience research; (iii) the computational limitations imposed by desktop computing and the inability to scale up analysis; (iv) the continued failure to support the temporal dimension, and especially dynamic processes and models with feedbacks; (v) the challenge of embracing a wider and more heterogeneous view of geographical representation and analysis; and (vi) the urgent need to foster an active software development community to redress some of these shortcomings. A brief discussion then summarizes the issues and suggests that GIScience needs to work harder as a community to become more relevant to the broader geographic field and meet a bigger set of representation, analysis, and modelling needs.  相似文献   
32.
为明晰明代石拱桥的结构性能,并提出适宜的加固修缮方法,以典型的明代石拱桥永昌桥为例进行研究。首先对其进行精确测绘,获得其准确可靠的几何信息;然后对其建筑形制、构造工艺及残损状况进行研究,为结构性能分析提供依据;接着利用ANSYS软件建立永昌桥主体结构的有限元模型,进行包括荷载影响分析、重要度分析和裂缝分析的结构性能研究;最后基于现状分析和结构性能研究,通过对比拱背套钢筋混凝土拱加固法和拱背粘贴碳纤维布加固法对石拱桥的结构性能的影响,提出了明代石拱桥永昌桥的加固修缮方法。研究成果可为同类型石拱桥的加固修缮提供参考。  相似文献   
33.
The Morgantina archaeological area, inhabited from the Early Bronze Age, had its widest expansion from the fifth to the first century bc . The volcanic millstones found at Morgantina fall into three different groups on the basis of the milling technique: (i) saddle querns (known from the Middle–Late Bronze Age and Iron Age); (ii) rectangular hopper‐rubbers (Olynthian) millstones, the invention of which dates to the fifth century bc ; and finally (iii) Morgantina‐type rotary millstones (starting to be used from the fourth to the third century bc ). In order to determine the provenance of the raw materials (lavas) used for all these millstone types, we collected 38 very small rock samples for thin‐section modal mineralogy, petrography and major trace element composition. The results have contributed to classifying different lithotypes and distinguishing between provenance from Etna and the Hyblean Mountains, the two volcanic areas respectively north‐east and south‐east of Morgantina. Saddle querns are made of tholeiitic basaltic andesites from the Hyblean Mountains and transitional basalts, mugearites and hawaiites from Etna. The variety of sources of portable saddle querns, mostly used in households, indicate that there was no general preference for specific quarrying sites. By contrast, the rectangular hopper‐rubber and the Morgantina‐type millstones, which document the period of Morgantina's greatest prosperity, are almost completely made of hawaiites from Etna. The use of a specific lithotype (i.e., Etna hawaiite) for the more efficient rectangular hopper‐rubber and rotary millstones could be linked to the fact that these mills may have been operated in business establishments. It is worth noting that the Gornalunga river was, in antiquity, a waterway joining Morgantina to the final stretch of the Simeto river and then the Ionian coast. The best candidate areas for the millstone hawaiite quarrying sites from Etna are the far south‐western sectors of the volcano, along the Simeto Valley (i.e., the ‘Piano Provenzana’ Formation) or the inner suburb of present‐day Catania (i.e., the ‘Pietracannone’ Formation). The very efficient Morgantina‐type rotary millstones spread during the reign of Hieron II of Syracuse (275–215 bc ) in eastern Sicily and met the need for grinding large quantities of cereals during a relatively peaceful time and a period of agricultural development.  相似文献   
34.
古建油饰彩画的制作技术分析研究   总被引:1,自引:0,他引:1  
为了对中国特有的古建油饰彩画制作技术加深了解,促进古建油饰彩画传统工艺科学化,采用X射线衍射仪、X射线荧光光谱仪、扫描电镜、体视显微镜等仪器对采自蒙古博格达汗宫博物馆、北京颐和园、甘肃嘉峪关、山西太符观等古代建筑的油饰彩画样品的制作技术进行了分析研究。结果表明,测试的样品分别采用了一麻五灰、一布四灰、单披灰等多种工艺制作地仗;麻纤维广泛应用于样品纤维层中,仅样品YHY-22使用了棉布;颐和园和博格达汉宫博物馆的样品以砖灰作为地仗无机填料,嘉峪关样品使用了白土粉,而山西古建样品则可能使用当地的土壤。可以得出结论:几个地区古建油饰彩画的制作材料和技术是有所不同的。  相似文献   
35.
This article considered glazed tiles excavated from the Ming Imperial Palace site in Nanjing as the research object. Glazed tiles were selected and analyzed via vacuum porosimeter, thermal dilation (TD), X-ray diffraction (XRD), and energy dispersive X-ray fluorescence (EDXRF) to determine their physical property, firing temperature, phase composition, and chemical composition, respectively. Results show that the firing temperature of body belongs to the temperature range (of 950–1,100°C), whereas the water absorption and apparent porosity are large. The phase composition of glazed tile bodies is the same (predominantly quartz and mullite). However, some samples contain trace amounts of rutile, hematite, sodalite, and orthoclase. The firing temperature combined with the phase composition indicates that the raw material and firing process of glazed tile body samples have similarities, which embody of the strict and unified management system of the official kiln. The raw materials of glazed tile body in the Ming Imperial Palace site may come from Dangtu glazed kiln, whereas the rest of the samples remains to be explored. This study provides a scientific basis for understanding the evolution of glazed tile-making technology in ancient China, and is important for the protection and repair of glazed buildings in the Ming Dynasty.  相似文献   
36.
中国古典四大民间故事乃民族瑰宝,其故事中的女主人翁全都流露出民主意识的萌芽,自由意识的觉醒和对未来世界的探寻。她们既是中华女性的楷模,也是人类女性的偶像。无论是情节、主题、人物、手法,四大民间故事都烙有鲜明、深刻、独特的民族印记。  相似文献   
37.
作者通过X光照相无损检测分析方法,搞清了西周癧父的现状;以及器物与体连接部位和盖内部的结构形貌,并主要介绍了该器物的铸造技术特征和保护处理方法。  相似文献   
38.
为探讨东周楚式戈斑纹的处理技术,采用金相显微镜、SEM、EDS、EBSD研究了上海博物馆藏的楚式斑纹戈的成分、显微组织和相组成,讨论了其制作工艺.结果表明:东周楚式戈富锡层厚度不均,以十余μm左右的厚度居多,最多处由4种不同物相组成,分别为η相、ε相、σ相及(α+δ)共析相.富锡层与基体之广日j没有明显的分界线.与现有其它富锡工艺研究成果进行比较,认为此件楚式戈与其它地域的富锡技术具有共同的工艺特征,应为热镀锡工艺.但在工艺参数掌控方面应呈现地域上的差异.  相似文献   
39.
宣笔在中国毛笔发展史上具有重要地位,不仅是唐宋时期毛笔的杰出代表,而且对湖笔等毛笔制作技艺的发展产生过重要影响。宣笔兴起的主因是拥有原料优势,持续蓬勃发展的动力是掌握核心技艺和不断推陈出新,最终走向衰落则受到政治、经济、文化等社会因素变迁的影响。  相似文献   
40.
中国先民使用红色颜料的历史悠久,最早可以追溯到新石器时期,它在中国的物质生产和文化发展中发挥了重要的作用。在2006年发掘的大房郢水库汉墓群中发现了两种红色颜料,通过采用X射线衍射、X射线荧光分析和傅立叶变换红外分析等分析方法对其进行了研究,发现它们是赤铁矿(α-Fe2O3)和朱砂(HgS),其用途分别为制造化妆品和红色漆膜。  相似文献   
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