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991.
辽宁沈阳、抚顺两地分布着众多的明代城址,这些城址是明九镇之一“辽东镇”军事防御系统的重要组成部分。长城资源调查工作结束后,我们对沈阳、抚顺地区明长城墙体两侧1000米以外的明代城址进行了野外调查。根据调查成果并结合文献记载,对这些城址的规模、结构和保存现状等信息进行了系统梳理,并对其功能和历史沿革进行了初步研究。  相似文献   
992.
以文化遗产保护为研究对象和学科体系的文化遗产保护学,具备学科建设的各种要素,但现有学科现状不能满足文化遗产保护事业发展需要,而明确学科地位,处理好其他相关学科与文化遗产保护学的关系,加强建设学科队伍和科研建设是文化遗产保护学科建设的基本途径。  相似文献   
993.
中国文物保护事业的发展是紧紧伴随着现代科学技术的发展而发展的.经过清末的国门被打开、建国后的现代化建设以及改革开放后的科学发展,现代科学技术数度冲击促进着我国的发展,推动文物保护工作上了三个台阶,并具有显著特征.展望现代科学技术在文物保护中应用研究的同时,我们也要认识到建立文物保护理论体系和文物保护技术方法的重要性.  相似文献   
994.
The Minjiang River terrace along the Longmen Shan fault zone near Wenchuan, at the eastern margin of the Tibetan Plateau, China, provides archives for tectonic activity and quaternary climate change. However, previous studies were not able to provide ages older than 100 ka due to the limitations of dating material or/and methods applied to date the fluvial sediments. In this study, we used the ESR signal of the Ti-Li center in quartz to obtain the ages of four higher terraces (T3–T6). According to the results, the terraces T3 to T6 were formed at 64±19 ka, 101±15 ka, 153±33 ka, and 423±115 ka, respectively. Combined with previous studies, these results indicate that the formations of all terraces correspond to glacial/interglacial transition periods, such as, T1-T5 being correlated to MIS2/1, MIS4/3, MIS5d/5c, and MIS6/5e respectively, while T6 probably to MIS12/11. According to these data, it is found that the average incision rate was significantly higher over the last 150 ka than that previous 100 ka (250 to 150 ka). As both tectonics and climate have affected the formation of these terraces, in addition to the overall uplifting of Tibetan Plateau, the regional uplift due to isostasy would be an additional tectonic factor in the formation of river terraces in the eastern margin of Tibetan plateau.  相似文献   
995.
Liu, Q., Khramov, A.V. & Zhang, H.C., 21.4.2015. A new species of Kalligramma Walther, 1904 Walther, J., 1904. Die Fauna der Solnhofener Plattenkalke bionomisch betrachtet. Denkschriften der Medizinisch-Naturwissenschaftlichen Gesellschaft zu Jena 11, 133214. [Google Scholar] (Insecta, Neuroptera, Kalligrammatidae) from the Middle–Upper Jurassic of Daohugou, Inner Mongolia, China. Alcheringa 39, XXX–XXX. ISSN 0311-5518.

A new species of Kalligramma Walther, 1904 Walther, J., 1904. Die Fauna der Solnhofener Plattenkalke bionomisch betrachtet. Denkschriften der Medizinisch-Naturwissenschaftlichen Gesellschaft zu Jena 11, 133214. [Google Scholar] (Insecta, Neuroptera, Kalligrammatidae) is described as Kalligramma delicatum based on a nearly complete forewing from the Middle–Upper Jurassic of Daohugou, Inner Mongolia, China. The new species is characterized by the narrow costal space with sinuous costal veinlets, Rs with eight primary branches, MP with five pectinate branches and 1A forked beyond its mid-length. The forewing of Kalligramma can be distinguished from the hind wing by its ovate rather than subtriangular shape, significantly wider costal space and more numerous crossveins between costal veinlets. The new species is interpreted to represent a forewing based mainly on its shape.

Qing Liu [] and Haichun Zhang [], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing, 210008, PR China; Aleksandr V. Khramov [], Borissiak Paleontological Institute of the Russian Academy of Sciences, Moscow, 117997, Russia. Received 10.12.2014; revised 11.2.2015; accepted 17.2.2015.  相似文献   
996.
<正>The concept of"purity"and"pollution"exists in every ethnic group or culture,and the emergence and existence of this concept is closely associated with geographic environment,religious belief,mode of production,lifestyle,morals and world outlook,and is supported and restricted by a whole set of cultural logics hidden deeply in the social structure.Different ethnic groups and cultures have different criteria for classification of"purity"and"pollution".One article,behavior or social phenomenon may be deemed"pure"by one ethnic group,but"polluted"by another.The human perception of"purity"is a  相似文献   
997.
徐浩 《史学理论研究》2013,(1):93-105,160
中世纪的西欧工匠是一个非常重要的劳动者群体。他们包括自由人和不自由人,后者在中世纪较早摆脱了奴役,成为半自由人和自由人;他们的人口比例不断上升,中世纪中晚期城乡工匠大约占到总人口的10%—20%,平均在15%左右,构成非农业人口的主体;他们主要以工业生产为生,随着中世纪中期和晚期工业品价格和工资从缓慢增长到快速上升,工匠收入的购买力也相应经历了从下降到提高的过程,15世纪时工匠的生活水平得到明显改善。  相似文献   
998.
As only a very limited number of earthquake strong ground motion records are available in southwest Western Australia (SWWA), it is difficult to derive a reliable and unbiased strong ground motion attenuation model based on these data. To overcome this, in this study a combined approach is used to simulate ground motions. First, the stochastic approach is used to simulate ground motion time histories at various epicentral distances from small earthquake events. Then, the Green's function method, with the stochastically simulated time histories as input, is used to generate large event ground motion time histories. Comparing the Fourier spectra of the simulated motions with the recorded motions of a ML6.2 event in Cadoux in June 1979 and a ML5.5 event in Meckering in January 1990, provides good evidence in support of this method. This approach is then used to simulate a series of ground motion time histories from earthquakes of varying magnitudes and distances. From the regression analyses of these simulated data, the attenuation relations of peak ground acceleration (PGA), peak ground velocity (PGV), and response spectrum of ground motions on rock site in SWWA are derived.  相似文献   
999.
The completeness of the complex response spectrum method for both formally underdamped and overdamped modes is theoretically proved, and the physical meanings of the decoupled modes as well as involved parameters are recognized and clarified in this paper. For the system with relatively large non-classical damping, the eigenvalue pairs generated by the complex mode decomposition method are real and the so-called modal damping ratios are larger than unity. In this paper, we firstly clarified that the decoupled modes are virtual and the so-called modal frequency and damping ratio are mathematical parameters that have no physical meaning. Then, the completeness of the complex response spectrum method for both formally underdamped and overdamped modes is rigorously proved by allowing the “damping frequency” to be an imaginary number. For the virtually overdamped modes, Duhamel integral involved in the calculation for formally underdamped modes automatically convert to hyperbolic Duhamel integral. A numerical example taken from the published literature is given to verify this method. Structural responses for the system with coupled damping under multi-support seismic excitations are further analyzed and numerical results indicate the accuracy of complex response spectrum method.  相似文献   
1000.
大清定鼎中原前夕和之后一个半世纪,在满汉文化思想接触、碰撞、相互融合的历史过程中,清帝出自居安思危、巩固皇权和延缓政权衰落周期的目的,在皇族宗室子孙、八旗子弟及中枢臣僚中开展民族传统教育,强调“力戒汉俗”、“不忘满洲骑射旧俗”,并将其视为“祖宗家法”和与国家民族命运攸关的基本教育之法。自太宗至仁宗嬗递六代,其间因各朝政治形势和教育针对性的变化,发生诸多修正,由此反映出社会进步的历程。  相似文献   
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