蝴蝶住宅楼 奥地利布尔根兰

正"蝴蝶屋"位于Hohe Warte气象站附近,曾有数位奥地利总统隐居于此,五座住宅楼就像五只黄蝴蝶飘落在这块天堂般的园林中。正是"GERNER GERNER PLUS"铸就了这份飘逸。整片土地占地约1公顷左右,核心元素并非住宅楼,而是茂盛的树木,这也是从设计之初就确定下来的。设计师并没有把五座住宅楼连成一片,反而在各个住宅楼间设置绿色景观。"闭上眼睛,想象一只美丽的黄蝴蝶刚刚落在院子里,如此轻盈。"这就是设计师对"蝴蝶屋"的外形描述。除此之外,在     

钢筋混凝土框架边柱突然失效模拟试验与分析研究

在偶然荷载作用下结构的失效机理是结构设计研究的重要内容。为研究框架结构在边柱突然失效瞬间结构的动力反应、内力重分布和破坏形态,湖南大学与美国南加州大学(USC)、美国加州大学戴维斯分校(UCDAVIS)、美国国家标准技术研究所(NIST)共同进行了1/2比例的3层3跨钢筋混凝土空间框架的倒塌试验。通过研究破坏瞬间结构的位移反应、加速度反应、钢筋应变和裂缝分布情况,揭示结构在竖向构件突然失效时结构的抗倒塌性能。研究结果表明按照抗震规范进行设计的框架结构在底层单个边柱突然失效时具有较好的抗连续倒塌性能,动力效应对结构的影响并不显著。并采用SAP2000有限元软件对结构在竖向构件突然失效时的位移反应、内力变化进行模拟分析,分析结果与试验结果吻和良好。     

古代吐鲁番坎儿井工程技术与测量方法研究

本文通过文献资料法、访谈法、实地调查法等对吐鲁番坎儿井工程进行了工程测量技术方面的研究,并从传统测量学的角度系统地研究了吐鲁番坎儿井工程从勘探到工程施工方面的测量技术,最后总结了古代吐鲁番坎儿井工程高差测量原理和测量方法,这对于丰富和完善坎儿井研究以及对坎儿井起源与传播学说研究都具有十分重要的学术价值。     

Study of high-speed interaction processes between fluoropolymer projectiles and aluminum-based targets

The experimental results and numerical modeling of penetration process of fluoropolymer projectiles in aluminum-based targets are presented. Analysis of mathematical models for interaction of elastoplastic projectile and target without taking additional energy released during interaction of fluoropolymer and aluminum into consideration is carried out. Energy fraction which is spent effectively on the increase in cavity volume is determined. The experimental and calculated results of penetration by combined and inert projectiles are compared.     

Feasibility analysis of WDM links for radar applications

Active phased array antennas enhances the performance of modern radars by using multiple low power transmit/receive modules in place of a high power transmitter in conventional radars. Fully distributed phased array radars demand the distribution of various signals in radio frequency(RF) and digital domain for real time operation. This is normally achieved through complex and bulky coaxial distribution networks. In this work, we intend to tap the inherent advantages of fiber links with wavelength division multiplexed(WDM) technology and a feasibility study to adapt these links for radar applications is carried out. This is done by analysing various parameters like amplitude, delay, frequency and phase variation response of various radar waveforms over WDM links. This also includes performance evaluation of non-linear frequency modulation(NLFM) signals, known for better signal to noise ratio(SNR) to specific side lobe levels. NLFM waveforms are further analysed using pulse compression(PC) technique. Link evaluation is also carried out using a standard simulation environment and is then experimentally verified with other waveforms like RF continuous wave(CW), pulsed RF and digital signals. Synchronization signals are generated from this variable duty cycle digital signals during real time radar operation. During evaluation of digital signals, variable transient effects for different duty cycles are observed from an amplifier configuration. A suppression method is proposed to eliminate this transient effects. Further, the link delay response is investigated using different lengths of fiber spools. It can be inferred from the experimental results that WDM links are capable of handling various signals significant to radar applications.     

加拿大阿尔伯塔省油气监管最新变革

为了适应规模不断扩大的油砂开发新形势,保障油气资源安全、有序、环保和可持续的发展,加拿大阿尔伯塔省政府在原能源资源保护委员会的基础上成立了专业的能源开发监管机构(AER,Alberta Energy Regulator),该机构负责监管阿尔伯塔省境内所有与石油、天然气以及煤炭等相关的能源开发活动。文章从AER的成立、组织机构、主要监管职能和具体监管流程等几个方面介绍了阿尔伯塔省油气监管的这一最新变革。总结了阿尔伯塔能源监管机构专一化、监管程序化、监管透明化、高度的公众参与以及严格的环境保护监管等几个特点。建议我国的页岩气开发监管应该:合理规划页岩气开发管理框架;不断增强页岩气开发监管法规建设;采取多种措施,加强环保监管;进一步增加公民参与意识,保障公众权益。     

Surface-effect on detection ability of fluorescent Eu(btc) metal-organic frameworks to metal ions

Eu(btc)metal organic frameworks(MOFs)were prepared by co-precipitation method via 1,2,4-benzenetricarboxylic acids(H3btc)connecting with Eu³⁺ions,and the morphology was controlled from compact spherical to irregular honeycomb by adjusting the pH of reaction solutions.The luminescence properties of Eu(btc)MOFs are found to be related to the surface morphology of products,and the compact spherical one performs stronger emission intensity.The sensing ability of Eu(btc)MOFs to 11 kinds of metal ions was investigated and a prominent quenching effect occurrs in Fe³⁺,or Ni²⁺solutions.Based on UV—vis absorption analysis,an“ion-fence”model presents the competition to absorb exciting light between Eu(btc)MOFs and adsorbed metal ions.Based on Stern-Volmer equation,the Eu(btc)detection is found with higher Ksv value and a lower detection limit.Meanwhile,a higher sensing efficiency is confirmed in the Eu(btc)MOFs with loose honeycomb due to aggravating porous surface offering much more sites for metal ions.     

An adaptive supervised wide-area backupprotection scheme for transmission linesprotection

Background: The increasing penetration of a massive number of plug-in electric vehicles (PEVs) and distributed generators (DGs) into current power distribution networks imposes obvious challenges on power distribution network operation. Methods: This paper presents an optimal temporal-spatial scheduling strategy of PEV charging demand in the presence of DGs. The solution is designed to ensure the reliable and secure operation of the active power distribution networks, the randomness introduced by PEVs and DGs can be managed through the appropriate scheduling of the PEV charging demand, as the PEVs can be considered as mobile energy storage units. Results: As a result, the charging demands of PEVs are optimally scheduled temporally and spatially, which can improve the DG utilization efficiency as well as reduce the charging cost under real-time pricing (RTP). Conclusions: The proposed scheduling strategy is evaluated through a series of simulations and the numerical results demonstrate the effectiveness and the benefits of the proposed solution.     

美国加州活动断层探测及其成果应用

正引言本文简要介绍美国,特别是加利福尼亚州,活动断层探测填图及其成果在抗震减灾中的应用。为避免由地震产生的地表破裂对建筑物造成的直接破坏,加州州政府在1972年颁布了《AlquistPriolo地震断层区划法》(以下简称"AP法")。此后开始对活动断层系统探测并填制大比例尺活动断层分布图。截至目前,美国积累了大量有关发震断层的空间分布、几何特征及活动参数的资     

苹果园—焕发活力的老城区

正苹果园,中国常用词汇,石景山区中的公园、地铁站、小区等都以苹果园命名。项目背景该项目为石景山区小微公共绿地改造项目之一,石景山区小微公共绿地改造是石景山区由传统工业区向现代化首都新城区转型的示范性景观工程,涵盖北京市石景山区大部分城市重点区域。在城市复兴进程中,不同等级不同类型的城市公共空间的改造正逐渐地完善城市结