THE HAGELIN CIPHER MACHINE (M-209) Reconstruction of the Internal Settings

It is an Interesting and useful cryptanalytic problem to try to reconstruct the internal settings of the M-209 cipher machine, given the text of a message which has been obtained both in clear and enciphered form. Then it is considerably easier to decipher any further messages encrypted with the same internal settings. It turns out to be possible to do this reconstruction for rather short messages, of the order of 75 characters or so. Partial or incomplete solutions are generally possible with as few as 50 characters.     

Adaptability: A Low-Carbon Strategy

For all its merits, the craze for ‘zero-carbon’ new-build is arguably misleading. In fact, retrofitting or recycling existing building stock can be a more eco-friendly option than even the best-intentioned demolition and replacement. Simon Sturgis , managing director of London-based Sturgis Carbon Profiling, is an expert in assessing projects’ ‘green’ credentials. He describes different scenarios for two examples – a 19th-century London terraced house, and a standard out-of-town industrial warehouse/office building – that illustrate his point, and sets out the analytical methods used by his firm.     

小城镇建筑与环境整治工程设计研究——以武汉黄陂区木兰大道为例

由于城市化进程发展和建设的需要,小城镇也在一步步地追赶着城市的脚步,同时它也面临着街道立面整治的问题。该文以武汉市黄陂区木兰大道为例,主要探讨如何在符合小城镇经济和环境的原则下,对小城镇临街建筑进行改造,使其满足功能需求与心里需求。结合街道整治过程当中普遍遵循的原则,以及武汉的相关政策和要求,提出其改造思路,并且给出了一定的设计成果。     

Electrochemical reduction of ammonium 5-bromo-2′-deoxyuridine-5′-methylphosphonate: an inhibitor of cell growth

The electrochemical reduction of a cell growth inhibitor, ammonium 5-bromo-2′deoxyuridine-5′-methylphosphate (BrdUrdOPO₂Me), was investigated in order to compare its electrochemical properties with those of 5-bromo-2′-deoxyuridine (BrdUrd) and of 5-bromo-2′-deoxyuridine-5′-phosphate (BrdUMP). The derivatives f BrdUrd differ markedly in their electrochemical behavior from BrdUrd because of the influence of the methylphosphonate or phosphate groups. Current vs pH plots for BrdUrdOPO₂Me and BrdUMP decrease in the form of an acid dissociation curve and assume kinetic behaviour at high pH values. Controlled potential electrolysis at a stirred mercury cathode of BrdUrdOPO₂Me requires two electrons per mole. Autoradiochromatographic analysis of the electrolytic product of the tritium labeled ammoniumbromodeoxyuridine-5′-methyl[³H]phosphate shows that the methylphosphonate group remains intact during the course of the electrolysis. Electrolysis results in debromination and the product exhibits an uv spectrum identical to a 2′-deoxyuridine derivative.     

交通·景观·人——比较上海世纪大道与巴黎香榭丽舍大街

景观大道对于城市形态、城市景现有重要影响,而上海世纪大道是国内城市景观大道的典型代表。该文通过比较上海世纪大道与巴黎香榭丽舍大街的异同和差距,分析和探讨了国内城市景观大道存在的问题以及改进的方向,认为城市交通以及景观设置皆为人的活动服务,因此,国内景观大道的建设需要进一步强调人性化建设;加强城市、街道与普通市民生活之间的互动,从而提升街道和城市的活力,改善城市生活的品质。     

基于ArcView的Avenue开发数据处理扩展模块

本文简要介绍了桌面地理信息系统软件ArcView的基本结构和开发工具Avenue,着重探讨在AreView环境下利用二次开发功能开发AVX扩展模块,用于解决日常工作中遇到问题的具体实现方法。     

Expansive soil modified by waste steel slag and its application in subbase layer of highways

Steel slag is a waste by-product of the steel industry. The recycling usage of steel slag is limited due to the mutative chemical compositions it contains and its low cementation. In this investigation, the composition adjustment and activation of steel slag were studied to produce an optimal slag-based composite with improved cementation efficiency. The controlling moduli of cement clinker were introduced to standardise the composite. Subsequently, the composite was used to modify Hefei expansive soil (a kind of engineering waste for swelling properties) in embankment construction. The basic physical properties including free swelling ratio, California bearing ratio, unconfined compressive strength, microstructure, and mineral evolution were evaluated to understand the engineering performance and mechanism of modified expansive soils. The results show that the cementation of the slag was significantly improved after the composition adjustment and activation. Furthermore, the treated soil can satisfy the requirement of the Chinese standard for first-class road/highway when the composite incorporation ratio is more than 5%. The microstructural and mineralogical analysis shows that the component adjustment and activation enrich the cementation of the slag, resulting in the suppression of the swelling potential and improved strength. The above findings improve the reuse efficiency of steel slag, especially in expansive soil modifications.     

The Life of Space

The digital has revolutionised the notion of space that was formulated on the two-dimensional page in the Renaissance with the discovery of perspective and the printing press. Derrick de Kerckhove and Antonio Tursi explore how our ideas about space have been overturned since the onset of the computer and the many different ways that architects are reinterpreting them. Copyright © 2009 John Wiley & Sons, Ltd.