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A thousand years of loneliness? Globalization from the perspective of a city in a European periphery
Anders Lfgren 《Geoforum》2000,31(4)
Most cities face the challenge of increasing global and local change. Much of what has been said about cities in a globalized world has been concerned with large metropolitan cites. It has been postulated that increased competitiveness is the relevant response, and that urban governance has to change from managerialism to entrepeneurialism in order to cope with this challenge. The first part of the paper discusses some aspects of this body of theory, and the relevance for sub-national regional capitals. It also discusses how the scope of strategies depend on changing national and regional policies. The second part uses the case of Trondheim to discuss how these cities perceive and deal with globalization. Four policy options are discussed; the clientist strategy, the competitive strategy, the isolationist strategy and finally the option of doing nothing at all. The article concludes that global challenges will force local government in small cities to forge new strategies, but the preferred option is a clientist strategy rather than an entrepreneurial one, and the scope of strategy is national rather than global. Thus, when dealing with small peripheral cities and globalization, the range of perspectives must be extended beyond entrepreneurialism and competitiveness. 相似文献
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完成了基于TMS320VC5402 DSP的RS_485通信的硬件设计和软件编程.基于美国TI公司TMS320VC5402 DSP芯片的多通道缓冲口(McBSP)进行适当的硬件扩展,以SPI方式直接和MAXIM公司的MAX3100通用异步串行收发器接口,然后经Linear Technology公司的LTC1480超低功耗RS_485收发器,从而实现了一种新的基于RS_485标准接口串行通讯的数据传输,充分利用了DSP的片上资源,使硬件和软件结构尽量简单化. 相似文献
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造山带研究中有关复理石和磨拉石的几个问题 总被引:1,自引:0,他引:1
在造山带研究中,碰撞方式和时限的争议是全球造山带研究中的一个共同现状或面临的难题。利用复理石和磨拉石时代来限定碰撞时限是造山带研究的一项重要内容。本文首先综述了复理石和磨拉石从提出到广泛应用以及不同历史时期被赋予的构造含义;其次,根据其可能发育的构造环境,指出复理石和磨拉石纪录造山带的相关信息及其演变过程。被动陆缘复理石可能纪录了参与碰撞拼贴块体的亲缘性,而且被动陆缘、活动陆缘或者岛弧环境的复理石均形成于碰撞作用之前,因此最年轻的复理石时代可提供碰撞时间的下限;(周缘)前陆盆地的磨拉石形成于碰撞造山作用过程中,因此其最早的磨拉石沉积时代可用于限定碰撞时间的上限。从复理石到磨拉石地层的渐变过程(连续沉积)指示了碰撞构造事件的发生、以及之后的碰撞造山作用是均变过程,会发育不同尺度规模的不整合。因此,造山带中的不整合未必代表有重大构造事件的发生,而连续沉积并不表明没有大的构造事件。 相似文献
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在核电工业中,安全壳内观检查能够直观地反映出安全壳性能,是非常重要的一项工作。现阶段,内观检查中的安全壳内衬鼓包测量主要采取人工测量的方式进行,针对传统方法效率低等问题,本文研制出一套新型的鼓包测量系统。该系统基于树莓派平台,采用激光位移传感器和超声波测距传感器,实现了安全壳鼓包的自动测量及自动识别功能,提高了工作效率,降低了工作成本。此外,设计试验对本系统进行精度分析,实例表明本系统测量精度优于内观检查精度要求,具有实用性和可行性。 相似文献
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Martin C. Smith Shude Mao P. Woz´niak 《Monthly notices of the Royal Astronomical Society》2002,332(4):962-970
We present a systematic search for parallax microlensing events among a total of 512 microlensing candidates in the OGLE II data base for the 1997–1999 seasons. We fit each microlensing candidate with both the standard microlensing model and a parallax model that accounts for the Earth's motion around the Sun. We then search for the parallax signature by comparing the χ 2 of the standard and parallax models. For the events which show a significant improvement, we further use the 'duration' of the event and the signal-to-noise ratio as criteria to separate true parallax events from other noisy microlensing events. We have discovered one convincing new candidate, sc33_4505, and seven other marginal cases. The convincing candidate (sc33_4505) is caused by a slow-moving, and likely low-mass, object, similar to other known parallax events. We found that irregular sampling and gaps between observing seasons hamper the recovery of parallax events. We have also searched for long-duration events that do not show parallax signatures. The lack of parallax effects in a microlensing event puts a lower limit on the Einstein radius projected on to the observer plane, which in turn imposes a lower limit on the lens mass divided by the relative lens–source parallax. Most of the constraints are however quite weak. 相似文献
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Yiannis Tsapras † Keith Horne Richard Carson Javier Méndez Alvarez Dan Batcheldor Alister W. Graham Philip A. James Johan Knapen Hannah Quaintrell Ignacio Gonzalez Serrano Peter Sorensen Nick Wooder 《Monthly notices of the Royal Astronomical Society》2002,337(1):41-48
We present observations of eight Galactic bulge microlensing events taken with the 1.0-m Jacobus Kapteyn Telescope (JKT) on La Palma during 2000 June and July. The JKT observing schedule was optimized using a prioritizing algorithm to automatically update the target list. For most of these events we have sampled the light curves at times where no information was available from the OGLE alert team. We assume a point-source point-lens (PSPL) model and perform a maximum likelihood fit to both our data and the OGLE data to constrain the event parameters of the fit. We then refit the data assuming a binary lens and proceed to calculate the probability of detecting planets with mass ratio q = 10−3 . We have seen no clear signatures of planetary deviations on any of the eight events and we quantify constraints on the presence of planetary companions to the lensing stars. For two well-observed events, 2000BUL31 and 2000BUL33, our detection probabilities peak at ∼30 and ∼20 per cent respectively for q = 10−3 and a ∼ R E for a Δχ2 threshold value of 60. 相似文献
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为了方便国内学者对脉动变星进行研究,建立了一个数据库,目前包含了时间长达10 yr左右的巡天项目MAssive Compact Halo Objects(大质量致密银晕天体,MACHO)和Optical Gravitational Lensing Experiment(光学引力透镜实验,OGLE)发现的脉动变星,一共容纳了来自银河系核球与大小麦哲伦云中的共近23万颗变星.采用的软件是LAMP,即Linux+Apache+MySQL+PHP.数据库的使用通过网页的简单搜索界面实现,搜索参数主要是天体的赤经、赤纬和半径.鉴于本数据库的灵活性,将来很方便加入其他的变星数据. 相似文献