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51.
Coffeehouses have been a part of America's cultural landscape since the seventeenth century. Their fortunes have risen and fallen with the changing demand for coffee and consumer preferences. This paper examines their historic function of promoting social engagement as so‐called third places among independently owned coffeehouses in the city of Portland, Oregon. Individual coffeehouses were evaluated to determine the extent to which they provided a supportive physical environment for social engagement in which a space is transformed into a place and detailed patron behavior was recorded over a three‐week period. Few coffeehouses provided a supportive physical environment. The majority of coffeehouse patrons during the weekday and weekend ordered drinks ‘to go.’ Among those who stayed during the weekday most sat alone and worked. Coffeehouse are spaces to ‘be alone together.’ It was only on lunchtime weekends that coffeehouses were full of the sound of conversations. Further study should consider the effect of eliminating free Wi Fi and banning laptops on social engagement and whether other place attributes need to be incorporated to promote social engagement. 相似文献
52.
以IKONOS 1m分辨率遥感影像为例,对矿业开发活动中按露天开采面、开采硐口、固体废弃物、尾矿库、中转场地、矿山建筑等进行分类研究,总结以上六类地物在高分辨率遥感影像上的解译标志。 相似文献
53.
随着城市现代化建设的加快和完善,道路路名混乱或不规范给经济社会活动和人们的交往带来不便。如何切实加强地名管理和服务工作是地名管理部门,必须面对的问题。本文以深圳市路名管理信息系统项目为例,结合本人在道路数据采集建库过程中所遇到的问题,与大家共同探讨城市化进程中的路名管理。 相似文献
54.
对Mark5B监控系统软件的设计思想、软件功能、通讯机制等几个方面作了介绍。Mark5B记录系统是当今世界VLBI观测台站中广泛使用的最为先进的记录系统之一,也是VLBI终端系统的重要组成部分。研制Mark5B监控系统软件的主要目的是进一步提高VLBI终端记录系统的可靠性,保障VLBI联测数据有效和高质量。该软件是在Qt开发环境下采用signals/slots的安全类型机制,并在Qt creator IDE上设计图形界面,完成数据采集和网络通信工作。Mark5B监控系统不仅适用于VLBI天体物理测量观测、VLBI测地观测,而且适用于中国VLBI网(The Chinese VLBI Network,CVN)联测。 相似文献
55.
56.
Christopher Harker 《Geoforum》2011,42(3):306-315
This paper questions geographers’ ability to think about power and violence through different epistemological registers, specifically by examining the discursive production of Palestine as place in geopolitical studies. Although the banner of geopolitics groups together a variety of approaches, these studies more or less cohere around a very particular type of imaginative geography of place - as violent and political. Recent arguments for cosmopolitan approaches to place - particularly when encountering non-Euro/American sites - are used to argue for more diverse approaches to places such as Palestine within Anglophone geographical scholarship. Using research on Palestinian family spaces and spacings, an alternative approach is outlined that exposes some geographies of dealing with and getting by the Israeli Occupation that are largely ignored by geopolitical approaches. These tropes prompt a return, in the conclusion, to the question of how geographers analytically apprehend power and violence, and the possibilities for doing this at the limits of, and beyond, the framework of geopolitical analysis. 相似文献
57.
The cultural gap between Europe and Asia (at first political and then religious) saw an increase with the spread of Islam, which, to the European imagination, was synonymous with ‘foreign’. This separation grew after the discovery of America (1492) with the loss of the central commercial position of the Mediterranean reducing the level of contact between the countries of its basin. Traces of these changes can be recognized on historic Western maps in the transformation of their toponyms (place names). Through a comparative cartographic analysis, this paper examines some of the key changes and phases that occurred during the era. 相似文献
58.
Shi-ju Kang Bang-rong HuangTing Kang Ji-hua LiangYong-gang Zheng 《Chinese Astronomy and Astrophysics》2012
Based on the log-parabolic spectral energy distribution of electrons, and the homogeneous one-zone synchrotron self-Compton (SSC) model, the multiband spectral energy distribution of the BL Lac object S5 0716+714 is calculated. Compared with Paggi's result which is obtained by means of δ-function approximation, it is found that a certain difference exists between our result and Paggi's. The main reason leading to this difference may be that the δ-function approximation on the synchrotron radiation of a single electron loses a part of electron energy, and therefore affects the result of inverse Compton scattering. Applying this model to the results of the multi-band observations made at three different states of Mark 421: high, medium, and low, the results of theoretical calculations are coincident very well with the observational results under the three different states of the object. An analysis indicates that the observed different states of Mark 421 are probably caused by the variation of the electron distribution in the jet. 相似文献
59.
The velocity field in the galaxy Mark 8 is studied by means of observations with the 2.6-m telescope at the Byurakan Astrophysical
Observatory using the VAGR spectrograph. In the optical range, the central portion of this galaxy consists of five bright
condensations which are superassociations (SA). These studies were made in a wavelength range that encompasses images of the
galaxy in the Hα and [NII] λλ6548 and 6583Å emission lines. The radial velocity field was obtained. The velocities of all
the superassociations were measured and a rotation curve constructed for the galaxy. The relative intensities of the emission
lines have been determined. Images are constructed in the Hα and [NII] lines and in the red continuum. It is concluded that
the superassociations were formed together and are, as a whole, young. The shape of the rotation curve shows that Mark 8 is
an isolated galaxy with a composite multicomponent nucleus.
Translated from Astrofizika, Vol. 51, No. 4, pp. 543–553 (November 2008). 相似文献
60.
为了解决目前公众对地理信息公共服务平台地名地址数据现势性要求越来越高而传统基础测绘更新速度较慢、周期较长之间的矛盾,本文结合滨州市区的地名地址更新实例,探索了一种基于共享本底数据库的省、市联动协同更新策略,通过合理的任务区划分,按照统一的更新要求,实践有所侧重的核查更新策略,实现了地名地址数据的省、市协同共享,显著提高... 相似文献