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1.
在乡村振兴背景下,旅游生计成为乡村可持续发展的重要议题,但与之相关的研究较为匮乏。文章以栾川县重渡村为案例地,通过对亲代和子代进行半结构化访谈,探讨旅游生计代际传承的过程及其主要影响因素。研究发现:(1)旅游生计的代际传承经历了亲代生计开拓、子代培养和发展、共同经营、生计传承四个阶段,并与重渡村这一乡村旅游目的地起步、培育、快速发展、规范管理的生命周期相适应。(2)文化因素、主体因素和规制压力是影响生计传承的主要原因。(3)旅游生计的代际传承关乎乡村旅游的可持续发展和乡村振兴战略的有效实施,相关问题值得进一步探索和研究。 相似文献
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Zhaohui Pan Min Zhu You’An Zhu Liantao Jia 《Alcheringa: An Australasian Journal of Paleontology》2018,42(1):10-21
Pan, Z., Zhu, M., Zhu, Y. &; Jia, L., August 2017. A new antiarch placoderm from the Emsian (Early Devonian) of Wuding, Yunnan, China. Alcheringa 42, 10–21. ISSN 0311-5518.Wufengshania magniforaminis, a new genus and species of the Euantiarcha (Placodermi: Antiarcha), is described from the late Emsian (Early Devonian) of Wuding, Yunnan, southwestern China. The referred specimens were three-dimensionally preserved in black shales, allowing a high-resolution computed tomography reconstruction of anatomical details. The new euantiarch is characterized by a large orbital fenestra, an arched exoskeletal band around the orbital fenestra and a developed obtected nuchal area of the skull roof. Maximum parsimony analysis, using a revised data-set of antiarchs with 44 taxa and 66 characters, resolves Wufengshania gen. nov. as a member of the Bothriolepididae, which is characterized by the presence of the infraorbital sensory canal diverging on the lateral plate, and the nuchal plate with orbital facets. New analysis supports a sister group relationship between Dianolepis and the Bothriolepididae. Luquanolepis, a coeval euantiarch from the neighboring site of the new form, is referred to the Asterolepidoidei and represents the basalmost and earliest member of the Asterolepidoidei.Zhaohui Pan* [panzhaohui@ivpp. ac. cn], Min Zhu* [zhumin@ivpp. ac. cn], You’an Zhu? [zhuyouan@ivpp. ac. cn] and Liantao Jia [jialiantao@ivpp. ac. cn] Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, PR China. *Also affiliated with University of Chinese Academy of Sciences, Beijing, 100049, PR China. ?Also affiliated with Uppsala University, PO Box 256, 751 05 Uppsala, Sweden. 相似文献
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In this paper, the Member Discrete Element Method (MDEM) is modified and perfected for three aspects: the algorithm itself, loading and computational efficiency, and to accurately and quantitatively simulate the progressive collapse for large-span spatial steel structures. In addition, the corresponding computational programs are compiled. First, from the perspective of the method, a meshing principle for discrete element models is determined, a treatment for material nonlinearity and strain rate effect is proposed, and a damping model is established. Next, the Displacement Method is introduced to determine the multi-support excitation for the MDEM, and then motion equations of particles under multi-support excitation are derived. On this basis, the specific process of gravitational field loading is presented. Furthermore, parallel implementation strategies for the MDEM based on OpenMP are constructed. Finally, the collapse simulation of a 1/3.5-scaled single-layer reticulated dome shaking table test model under multi-support excitation is carried out. The comparison demonstrates that the ultimate load and failure mode as well as the complete collapse time of the numerical results are consistent with the experimentally measured responses, and the configuration variations from member buckling and local depression until collapse failure are fully captured. Moreover, the displacement time-history curves obtained using MDEM are almost identical to the experimental measurements, and there is a nuance only in the amplitude. It is verified that MDEM is capable of precisely addressing the collapse failure for large-span spatial steel structures. Additionally, the failure mechanism for structures of this type is naturally revealed. 相似文献
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宋太祖开宝三年(970),南唐清辉殿学士张洎奉命使宋,纪录宋典客、左补阙贾黄中谈话,撰成<贾氏谈录>一书.此书虽记唐代琐事,又仅一卷,"篇帙无多,然如牛李之党其初肇衅于口语,为史所未及,而<周秦行纪>一书,晁公武亦尝据此录以辨韦璀之诬. 相似文献
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从《申报》看苏州的私钱与禁私(1827-1877) 总被引:1,自引:1,他引:0
清代实行银钱平行本位,大数用银,小数用钱。制钱是民间主要的流通货币,银两只不过是国家财政和大宗贸易的计算出纳单位以及富裕人家的储藏手段。在清朝统治者入关前,就曾铸有“天命”、“天聪”两种铜钱,自顺治进关,到辛亥革命,前后历经十代皇帝,铸有十种年号钱。康熙、乾隆时代的铜钱质量、重量都很规范。 相似文献
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论碧霞元君信仰的起源 总被引:2,自引:0,他引:2
泰山碧霞元君是中国历史上影响最大的女神之一,尤其是明清以来,她在民间的影响已经大大超过了泰山主神东岳大帝,以至于当时的文人士子对碧霞元君势力 相似文献
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浙江平湖庄桥坟遗址出土的石犁是史前考古的新发现,属于痕迹文物。出土时木构件痕迹饱水,为暗褐色、开裂严重、整体呈腐蚀状,非常脆弱。针对器物的保存状况,因地制宜地制定一系列保护方法:木构件痕迹的脱水保护、底托的加固制作、木构件粘贴复原等,使文物得以长期保存。 相似文献