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In Chinese traditional timber buildings, stitching is very common. When the bearing capacity or the rigidity is inadequate, a timber beam is often strengthened with another beam using the stitching method. The timber stitching beams are mainly of two types—the small-top/big-bottom type and the big-top/small-bottom type. To study the bending behavior of these two types of timber stitching beams, including the failure mode, the flexural capacity, the strain distribution at mid-span section, and the maximum deflection, bending tests are carried out on 14 timber stitching beams with Chinese traditional conformation for seven pine beams and seven fir beams. The results show that the failure modes of the small-top/big-bottom type of stitching beams all show brittle fractures at the bottoms of the bottom beams. The failure modes of the big-top/small-bottom type of stitching beams all show brittle fractures at the bottoms of the top beams. The distribution of section strain along the height of each part of the beam basically obeys plane hypothesis. Based on the theoretical and experimental analysis, the calculation formulas of flexural capacity and maximum deflection of these two types of timber stitching beams made of pine and fir are presented.  相似文献   
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奚庆庆 《安徽史学》2015,(4):120-131
新中国建立前夕,鉴于英美在华的利益侧重点、外交传统以及与国民党及其政府的历史关系存在不同,两国在对华政策上出现分歧,最终在诸如是否撤出中国、是否对新中国实施贸易管制以及是否打破国民党对上海的封锁等系列问题上立场迥异,争执激烈,并最终各行其是。根本而言,这是英美经通盘考虑后从自身利益出发所做出的政策抉择,同时也是两国不同的外交传统在对华政策层面上的集中体现。  相似文献   
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Despite international pressure to condemn North Korea (DPRK), China’s successive leaderships have dealt carefully with Pyongyang, especially vis-à-vis its nuclear weapons program. This moderate stance reflects the two countries’ decades-long relationship, summarised in the Chinese idiom that Pyongyang and Beijing are “as close as lips and teeth”. Nevertheless, the DPRK’s third nuclear test in February 2013 raised enormous challenges for the new Xi Jinping leadership to maintain the previous DPRK policy focused on the status quo and stability on the Korean Peninsula. China’s attitudes and policies towards the DPRK after the provocative third test signified a possible reorientation of Beijing’s DPRK policy. This generated repercussions in the countries concerned and prompted debates among experts. This article asks how these events should be understood and what their implications are for the Xi leadership’s policy on the DPRK, the stability of the Korean Peninsula, and Northeast Asia. Given China’s competitive relations with other major powers, we conclude that the Xi leadership will not abandon the DPRK; indeed it will reinforce the policy of strengthening China’s influence over it. Nonetheless one aspect of doing so will involve China opening up to other – cooperative, multilateral – approaches to reinforcing stability on the Korean Peninsula and in Northeast Asia.  相似文献   
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Both Canada and the United States have “pivoted” toward Asia in their foreign policy over the past decade, although emphases in those pivots differed between the two countries. The former focuses on an economic pivot initially, the latter on a security one. What factors explain these shifts? What was the magnitude of policy change by both? Utilizing some important theoretical works by Charles Hermann, we discuss the factors that appear to have brought about this policy change toward Asia, outline the actions and activities that both countries have initiated toward Asia in the past decade to illustrate the type and magnitude of policy change that has occurred, and compare some areas of political, economic, and military similarities between Canada and the United States toward this region. Finally, we assess the likely future of these pivots to Asia in light of the change in political leadership within both nations.  相似文献   
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In 1865, the colonies of eastern British North America created a joint commission to investigate the possibility of reciprocal trade agreements with other parts of the Western hemisphere. In early 1866, the commissioners visited the West Indies and the Empire of Brazil, where they met officials and business leaders. No actual tariff agreements resulted from the commissioners’ travels, the main concrete result of the 1866 trade mission being the establishment of a direct steamship service between Canada and the West Indies. The study of contemporary discussions of the trade mission deepens our understanding of the history of relations between the British West Indies and British North America in the aftermath of emancipation and the end of the ‘Old Colonial System’. Moreover, these discussions reveal different elements of an emerging Canadian identity. Discourse of Britishness influenced the 1866 trade mission, but so did a sense of affinity linking Canada to the other monarchical territories in the Western hemisphere, such as the Empire of Brazil. For their part, some contemporaries in the West Indies welcomed the Canadian trade initiative because they wished for a counterweight to the growing influence of the United States in the region. The article also presents new information about British policy towards Latin America, particularly Mexico and Brazil, as well as British commercial diplomacy more generally. The article is based on materials in archives in the United Kingdom and Canada as well as a range of printed primary sources.  相似文献   
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Much has been written about how the American War of Independence, a key imperial event, affected the British Isles. However, within this body of work there is limited reference to Liverpool, which was arguably becoming ‘the second city of empire’. This article attempts to fill this gap in the historiography, and addresses the economic impact of the war upon this key port town. It shows that there were four overall stages to Liverpool’s foreign commerce during this period—initially trade remained broadly steady, then there was a noticeable decline, the penultimate stage marked a sluggish improvement, and finally it was not until the post-war years that a sustained recovery took hold. That said, despite these overall trends, individual markets such as the trans-Atlantic slave trade often had their own dynamics. Although privateers (private ships of war) contributed towards the town’s eventual commercial recovery, this activity was by no means the only factor in explaining this rebound. Furthermore, the American war had an impact upon other sectors of the Liverpudlian economy, including shipbuilding and infrastructure projects. Combined, this evidence suggests that eighteenth-century warfare had positive and negative repercussions for the UK economy. As a result, we learn more about being ‘at home with the empire’.  相似文献   
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ABSTRACT

The highest number of German scholars and physicians, forced by the National Socialist regime to emigrate for “race” or political reasons, were from Berlin. Language and medical exams were requested differently in their new host country—the United States—leading to a concentration of immigrants in the New York and Boston areas. Very early Emergency Committees in Aid of German Scholars and Physicians were established. Undergraduate students (like F. A. Freyhan, H. Lehmann, and H.-L. Teuber) from Berlin seemed to integrate easily, in contrast to colleagues of more advanced age. Some of the former chiefs and senior assistants of Berlin’s neurological departments could achieve a successful resettlement (C. E. Benda, E. Haase, C. F. List, and F. Quadfasel) and some a minor degree of success (F. H. Lewy and K. Goldstein). A group of neuropsychiatrists from Bonhoeffer’s staff at the Berlin Charité Hospital could rely on the forceful intercession of their former chief. The impact of the émigré colleagues on North American neuroscience is traced in some cases. Apart from the influential field of psychoanalysis, a more diffuse infiltration of German and European neuropsychiatry may be assumed. The contribution to the postwar blossoming of neuropsychology by the émigré neuroscientists K. Goldstein, F. Quadfasel, and H.-L. Teuber is demonstrated in this article.  相似文献   
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