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排序方式: 共有381条查询结果,搜索用时 31 毫秒
1.
Andreas Butter 《Planning Perspectives》2018,33(2):249-269
For decades, German Democratic Republic (GDR) architecture was seen as parochial and dictated by the Soviets, yet increasing scholarly interest has generated a picture of debates and specific practices that were embedded in the global process of expansion and crisis of Modernism. Meanwhile, and influenced by the East-West conflict, competing concepts of modernization and national identity arose in the so-called Third World, initiating multifarious cultural transfer processes. This article analyses to what extent the architects from the GDR – a country whose building practice was increasingly shaped by the principles of industrial prefabrication – have played a part in regional contexts and construction methods. It also asks what their role was in international organizations such as Union Internationale des Architects and UNESCO, which promoted their practical engagement abroad. The subject raises issues of possible freedom of action in creative design and fusion processes, but also of bureaucratic constrictions and international relationships ending in unexpected conflicts. The examples outline the field of activities that stretches from pure blueprint delivery for a memorial competition to long-standing work on location when planning whole neighbourhoods. Furthermore, the article examines how the challenges of international planning impacted building culture within the GDR itself. 相似文献
2.
AbstractCryptographic attacks are typically constructed by black-box methods and combinations of simpler properties, for example in [Generalised] Linear Cryptanalysis. In this article, we work with a more recent white-box algebraic-constructive methodology. Polynomial invariant attacks on a block cipher are constructed explicitly through the study of the space of Boolean polynomials which does not have a unique factorisation and solving the so-called Fundamental Equation (FE). Some recent invariant attacks are quite symmetric and exhibit some sort of clear structure, or work only when the Boolean function is degenerate. As a proof of concept, we construct an attack where a highly irregular product of seven polynomials is an invariant for any number of rounds for T-310 under certain conditions on the long term key and for any key and any IV. A key feature of our attack is that it works for any Boolean function which satisfies a specific annihilation property. We evaluate very precisely the probability that our attack works when the Boolean function is chosen uniformly at random. 相似文献
3.
Betsy Rohaly Smoot 《Cryptologia》2021,45(1):81-87
Abstract This article discusses source material for studying US cryptologic efforts during World War I. Much of this material was used to prepare the forthcoming publication from NSA’s Center for Cryptologic History, From the Ground Up: American Cryptology During World War I. The author suggests areas for additional scholarship in the field. 相似文献
4.
The last few years have seen many studies of large post-Second World War housing estates. At present they are often the most deprived areas of European cities. The turnover of the population on these estates is characteristically rapid, leading to considerable socio-economic and socio-cultural changes and a multi-ethnic neighbourhood. Such areas often have to contend with severe physical, social and economic problems and the consequent dissatisfaction of the residents. This combination of rapid and selective population turnover and increasing numbers of problems may well affect aspects of social cohesion within these neighbourhoods, particularly the social networks. This process is regrettable, because social cohesion is regarded in a positive light, something that enhances the quality of life. Stimulating social cohesion is therefore an important objective of many policies that focus on large post-Second World War housing estates. The authors have found it interesting to discover how important social cohesion is in the opinions and the lives of the inhabitants rather than the policy makers. In their opinion, urban policies focus on social cohesion while the inhabitants' views of its relevance are unknown. On the basis of this paper, certain aspects of social cohesion in large post-Second World War housing estates appear to be valued, but housing market behaviour, such as residential moves, is hardly affected by aspects of social cohesion. Other aspects, such as moving to a better house, are much more relevant. The results may put into doubt the stress placed in urban policies on social cohesion. 相似文献
5.
为了查明金川二矿区铜镍混合精矿镁含量高的原因,对现场混合精矿进行了工艺矿物学研究。结果表明:混合精矿中主要含镁脉石矿物为蛇纹石,其次是辉石、橄榄石、绿泥石和滑石等;混合精矿中主要铜、镍矿物粒度虽然微细,但其解离度均不高,仅有60%左右,强化对铜、镍矿物的回收客观上为易浮含镁脉石矿物单体及与铜、镍矿物的连生体进入混合精矿创造了条件;混合精矿中含镁脉石矿物多以视同单体的形式存在,其次是以磁铁矿连生体的形式存在,这是造成混合精矿镁含量较高的主要原因;主要含镁脉石矿物可浮性从高到低的顺序是滑石>菱镁矿>辉石>蛇纹石>绿泥石>橄榄石。因此,要降低铜镍混合精矿的MgO含量,提高铜、镍矿物的解离度虽然重要,但有针对性地抑制含镁脉石矿物单体及与磁铁矿的连生体上浮是关键。 相似文献
6.
Anoma Pieris 《Architectural Theory Review》2013,18(3):364-385
Colonial-period military estates in Singapore are being gentrified for adaptive reuse producing high-end hospitality and retail venues for expatriate and tourist consumption. These include the feted “Black and White” residential enclaves synonymous with Singapore’s tropical aesthetic. But underlying this reinvention is a disturbing history of wartime repurposing under the Japanese Imperial Army, which temporarily destabilised the meanings and representations of these buildings. The seemingly undisturbed architectural typologies of barracks, bungalows and timber huts were backdrops to war, military occupation and captivity. This paper explores how the aesthetic affects and affectations that accompany adaptive reuse may conceal or disclose unsettling histories. It contrasts contemporary celebration of these revitalised historical neighbourhoods with their very different representation by wartime captives. 相似文献
7.
Hugh Clout 《Landscape Research》2013,38(3):213-230
The reconstruction of devastated farms, villages and market towns in northern France was not masterminded by the state or carried out by its emergency agencies, which were concerned with filling trenches, removing shells, restoring farmland and patching up ruins. Segments of French society needed to mobilize themselves to declare their losses and claim compensation from the state. Proposals by French trades unionists to bring in German building workers to reconstruct rural settlements were rejected. Instead, general purpose reconstruction co‐operatives were established, first in Lorraine and then throughout the régions dévastées. It is argued that the differing attitudes to religion and trades unionism in the countryside of northern France were reflected in the varying efforts made to effect rural reconstruction during the 1920s. The dream of international labour solidarity through reconstruction was not realized. Rather, restoration of northern France was undertaken by private construction companies, often contracted to general‐purpose co‐operatives. 相似文献
8.
9.
Hanne Van den Berghe W. Gheyle B. Stichelbaut T. Saey N. Note M. Van Meirvenne 《Landscape Research》2019,44(4):351-373
The First World War (WWI) had a notable influence on the landscape at the former Western Front in Belgium. Research on a landscape scale is necessary to understand the destructive and constructive impact of the war and its consequences for the post-war landscape in a holistic manner. This paper focuses on the trajectory and impact analysis of three study areas with contrasting landscape types and aims to indicate possible preserved military relics today. Therefore, landscape changes are studied using historical aerial photographs (WWI and WWII) and contemporary orthophotos. A military landscape characterisation is made based on land use/land cover and linear structures that were mapped throughout time. Specific landscape trajectories could be designated as areas with a possible preservation of WWI heritage, with a related impact degree. The results are useful for sustainable heritage management and for further interdisciplinary research on WWI-heritage, by providing a broad knowledge of the area. 相似文献
10.
LOUIS KRUH 《Cryptologia》2013,37(1):2-9
Abstract This article presents the original draft of the Zimmermann telegram from 1917 in facsimile. Its various annotations provide interesting insights, such as the idea to promise California to Japan and instructions concerning transmission and encryption. Further documents clarify how the telegram was sent and put various alternatives suggested in the literature to rest. The political background and fallout in Germany are discussed, as well. 相似文献