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71.
卷轴是书画艺术的一种独特展示与收藏形式,卷轴书画画芯表面的折痕不仅影响展陈效果,而且降低了书画文物的保存寿命。为此,利用超景深显微镜和扫描电镜分析了卷轴书画折痕的微观结构,探讨了折痕产生的机理,并提出了相应的预防措施。结果表明:小直径收卷是书画产生折痕的重要原因之一;收卷直径越小,书画出现折痕的现象越明显。通过在地杆处加轴管以增大收卷直径,能够有效减少折痕和断裂的产生。该方法保持了中国传统卷轴书画的装裱形式,维持了书画的原貌,并能够有效保存书画展示的传统韵味。研究结果为探讨书画折痕产生的机理和防治对策研究提供科学依据。  相似文献   
72.
Abstract

This work proposes the term ‘naval elites’ in order to provide a new interpretation of social change in the eighteenth century from a comparative perspective. Naval elites, a social group formed by a part of the naval officer corps and midshipmen, are here defined as a historical instrument, the particular and intriguing features of which may be useful in the revision of some perspectives on social change. In particular, the authors analyse shifting power relationships through the reconsideration of naval patronage and bureaucracy, revisit the process of naval professionalization and the transformation of the concept of merit, and suggest that naval elites embodied new notions of social distinction and exclusiveness.  相似文献   
73.
The use of renewable hydraulic energy sources by mankind most likely has its origins in the development of the watermills. To understand the functioning of these mills, this article first reviews, through the analysis of different bibliographical sources, the technical evolution of the machinery used since the appearance of the first watermills to grind cereal grain in the 1st century bc.

Secondly, a particular area of the south-west of Spain, Alcalá de Guadaíra, has been selected for study, whose strategic location as well as its hydrological characteristics gave rise, firstly, to an intensive milling industry, and, later, a famed baking industry, from the late Middle Ages until recent decades. The huge development of these two industrial activities has made Alcalá de Guadaíra an exceptional example in Spain, with 40 watermills in the early 18th century.

Extensive work on site allowed the analysis of the state and types of watermills that still exist in this area, identifying their similarities and differences. Unfortunately, after they fell into disuse, only 28 of these mills remain today; 12 of them are in a relative good state of preservation, seven in an alarming state of ruin and, of the other nine, only some unrecognisable vestiges remain. Some of these mill buildings have been restored recently, although their machinery is missing. Only from old photographs or by visiting mills restored in other areas is it possible to determine how these watermills worked.

Due to the lack of financial resources to carry out physical restoration of the industrial heritage missing in these flour mills, a virtual model of one of them has been developed. This work provides, at least virtually, a reconstruction of the traditional mills which helps promote technological studies and shows how they worked, as part of virtual exhibitions. In addition, a computer application of augmented reality has been developed that any visitor can install on a mobile device to display the virtual reality of the machinery, generated by 3D models, so they can visualise the physical reality that they would have found in the mill.  相似文献   

74.
This article contributes to the debate on macroeconomic management and capital account regulations in developing and emerging countries (DECs). It argues that the recommendation by neoclassical economists and international financial institutions (IFIs) to combine an inflation‐targeting regime with exchange rate management, whilst maintaining open capital accounts, is not only impossible but also potentially counterproductive. The article draws on extensive semi‐structured interviews with currency traders in Brazil and London to show that this is due to the particular way such a regime shapes central bank interventions in the money and foreign exchange markets and the destabilizing way these interventions interact with financial market expectations. The interview results also demonstrate that the guidelines issued by IFIs actually undermine, rather than aid, DEC central banks’ initial attempts to manage excessive exchange rate movements. These results support the long‐standing argument by heterodox economists and critical international political economists that DECs need to make the exchange rate an explicit instrument and goal of their macroeconomic policy and complement it with comprehensive capital account regulations to reduce the destabilizing impact of international capital flows. The interview results also give some concrete suggestions on how to achieve this.  相似文献   
75.
This paper investigates zoning in a cross‐border linear city that consists of two bordering towns. In each town, a local regulator has a say in the location of the local firm. We find that local regulators may use zoning strategically. The incentive to gain consumers from the other town, or not to lose local consumers, may push regulators to approve only locations for firms close enough to the frontier. When zoning is costly an asymmetric equilibrium may emerge: only one regulator resorts to zoning. In the case of towns of different sizes, the regulator of the larger town is the only one that zones in an asymmetric equilibrium.  相似文献   
76.
77.
Portugal was the second country in Western Europe to ratify the 2001 UNESCO Convention, a pivotal step that occurred on September 21, 2006. In 2000 the Portuguese delegation presented a statement in the UNESCO meeting for the draft Convention, the substance of which emphasises the protection and cooperation principles concerning the underwater cultural heritage rather than the issue of its possession. In 2008, the discovery of a sixteenth century Portuguese shipwreck near Oranjemund, Namibia, confirmed that the referred statement opened a premonitory strategic window for the conciliation of interests of States around such examples of common heritage.  相似文献   
78.
ABSTRACT In industrializing regions, foreign investments often generate spillovers through regional backward links. This situation may create a gap between private and social valuations of resources, resulting in a level of local content below what would be optimal for the economy. This situation creates an opportunity for the enactment of domestic content regulations. This paper presents a model to understand how these policies condition the decisions of the economic agents and affect economic welfare. Then, it simulates the model using a case study of the automotive sector. Results suggest that, in certain conditions, this local content regulation can be welfare enhancing.  相似文献   
79.
80.
Setting limits on government action is critical to economic development. Some forms of government organization, such as market-preserving federalism, seem effective to protect property rights in the long term with good results for economic efficiency. Spain endowed its regions with “Statutes of Autonomy” in the 1980s thus moving from a centralized to a decentralized form of government. It renewed and expanded some of the statutes in the 2000s. This article investigates whether these two waves of regionalization, which had their own characteristics in each region, had led to positive effects on economic performance. Using a novel autonomous region/country-matched balanced sample for the period 1950–2016, we apply the synthetic control method and compare the economic growth trajectories of Spanish regions with their synthetic control groups not affected by the regionalization process. We show that the first wave of “Statutes of Autonomy” had a positive but temporary economic growth impact. By contrast, the second wave of regionalization of the 2000s is associated with a negative growth impact.  相似文献   
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