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1.
泰荣 《世界电信》2003,16(3):11-14
移动通信市场已经成为奥地利竞争程度较高的市场,主要的4家移动运营商分别是Mobilkom,Max.Mobil,Connect Austria和Tele.ring,其中Mobilkom占有的市场份额最大,奥地利政府于2000年11月拍卖了6张国内3G许可证,除了上述4家运营商获得3G许可证之外,奥地利Hutchison 3G和3G Mobile也得到了3G牌照.  相似文献   
2.
The historical record of in situ measurements of the terminus positions of the Pasterze and Kleines Fleißkees glaciers in the eastern Alps of Austria is used to assess uncertainties in the measurement of decadal scale changes using satellite data. Topographic maps beginning in 1893, and satellite data from 1976 to 2001, were studied in concert with ground measurements to measure glacier changes. Ground measurements show that the tongue of the Pasterze Glacier receded ∼1150 m from 1893 to 2001, while satellite-derived measurements, using August 2001 Landsat Enhanced Thematic Mapper Plus (ETM+) data registered to an 1893 topographic map, show a recession of 1300-1800 m, with an unknown error. The measurement accuracy depends on the registration technique and the pixel resolution of the sensor when two satellite images are used. When using topographic maps, an additional source of error is the accuracy of the glacier position shown on the map. Between 1976 and 2001, Landsat-derived measurements show a recession of the terminus of the Pasterze Glacier of 479±136 m (at an average rate of 19.1 m a−1) while measurements from the ground showed a recession of 428 m (at an average rate of 17.1 m a−1). Four-meter resolution Ikonos satellite images from 2000 and 2001 reveal a shrinkage of 22,096±46 m2 in the Pasterze tongue. The nearby Kleines Fleißkees glacier lost 30% of its area between 1984 and 2001, and the area of exposed ice increased by 0.44±0.0023 km2, according to Landsat satellite measurements. As more recent satellite images are utilized, especially data that are geocoded, the uncertainty associated with measuring glacier changes has decreased. It is not possible to assess the uncertainty when an old topographic map and a satellite image are coregistered.  相似文献   
3.
During operation, thermomechanical stresses occur in refractory linings. Under elevated stress and temperatures, these ceramics experience primary creep, which can further proceed to the secondary and tertiary creep stages. This necessitates a characterization of their three-stage creep behavior. Hence, two advanced uniaxial tensile and compressive creep testing devices are utilized. The Norton-Bailey creep equations and an inverse identification procedure are applied for the evaluation of the creep curves. To account for the full three-stage creep behavior in thermomechanical modelling activities, a creep-stage transition criterion is identified and subsequently implemented together with the Norton-Bailey creep-strain rate representations in a new developed creep model. The finite element simulation results from different creep testing procedures are in accordance with the corresponding experimental results of a magnesia-chromite refractory ceramic. The study also reveals the temperature-dependent asymmetrical creep behavior of the material in terms of the creep-strain rates and critical creep strains.  相似文献   
4.
Gasified biomass is a technology that has the potential to partially replace fossil fuels for the production of heat, electricity, transport fuels, synthetic natural gas (BioSNG) and chemicals. In the context of climate change, biomass gasification is an attractive technology. It is, however, still in the early phase of its diffusion and much of the knowledge resides in the academic sector and in small companies—the technological innovation system (TIS) is in the process of being formed. Austria is one of the leading European countries in this field and much of the development in Austria can be traced to one prominent individual, Professor Hermann Hofbauer at the Technical University of Vienna. The purpose of this paper is to analyze how and the extent to which an individual academic, Professor Hofbauer, has influenced the formation of a TIS centred on gasified biomass in Austria. We find that his impact is multidimensional and significant but that there is also a frictional and intentional resistance that obstructs the commercialisation of the new technology. These sources of resistance go beyond the ability of an individual system builder to handle. Policy makers, therefore, need to add a strong element of system building activities that interact with and supplement those pursued by Professor Hofbauer.  相似文献   
5.
This paper explores the role of distant knowledge links and policy actions for the development of biotechnology clusters. It seeks to challenge the prevailing view that the birth and early development of high technology industries are always spontaneous phenomena which are mainly based on local knowledge. Departing from the theoretical concept of regional innovation systems (RIS), a distinction between “RIS with strong potentials for high technology industries” and “RIS with weak potentials for high technology industries” will be drawn. It will be argued that in the latter case the development of biotechnology clusters is more dependent on distant knowledge sources and proactive policy efforts to create a favourable environment for high technology activities. Furthermore, it will be shown that a far-reaching transformation of the regional innovation system is crucial for catching-up processes of regions which are latecomers in high technology sectors such as biotechnology.  相似文献   
6.
This article examines the Austrian Homeland or Heimat movement through an investigation of Wilhelm Angerer's 1942 book of poems and photographs, A Song Sweeps Down from the Mountains (Ein Lied rauscht von den Bergen). The multifaceted, widespread regionalist or homeland movement infiltrated all areas of visual culture, from tourist postcards and popular films to high‐quality picture books and exhibition prints. In considering the book by Angerer, this article highlights an intersection of modernity with tradition, defined in terms of a popular visual culture that formed a distinct and complex concept of the Austrian Heimat.  相似文献   
7.
Hilel Legmann   《Geothermics》2003,32(4-6):497
The 250 kW geothermal project at Bad Blumau is the first geothermal project developed in Austria by the private sector following the deregulation of the electricity industry in this country. What makes the project unique besides its private ownership structure is its ability to generate electrical power and district heating for the Rogner Bad Blumau Hotel & Spa by using a low temperature geothermal resource. Installed in the record time of less than a week, the air-cooled ORMAT ® Energy Converter (OEC) CHP module has been in commercial operation since July 2001. With an annual availability exceeding 99%, between October 2001 and December 2002 the plant delivered 1,560,000 kWh to the local grid. The geothermal CHP module utilizes brine at 110 °C, available from a 3000 m deep production well. Exiting the OEC unit at a temperature of 85 °C, the brine is then fed into the district heating system, providing heat for the Rogner Bad Blumau Hotel & Spa. The geothermal brine is returned from the district heating system and injected into a 3000 m depth reinjection well. The system is a pollution-free, unattended operating power generation module, which has avoided more than 1100 kg of CO2 emissions over its first operating year.  相似文献   
8.
介绍奥地利境内的多瑙河梯级水电站群在设计及管理上的特色。其规划中的 12座水电站 (已建成 9座 ) ,实行一家业主管理 ,在诸如闸门、船闸、厂房活动盖板、坝顶双向门机等实行统一尺寸 ,以使设计简单 ;电站的高度自动化和运行的可靠性 ,使其在电站的运行中实现了无人 (少人 )值守管理 ;电站内除了水工建筑物外 ,再无学校、医院、职工生活区等设施  相似文献   
9.
In the present study, aluminum nitride-carbon (AlN-C) nanocomposites are synthesized through a green, facile and inexpensive mechanochemical route. Well-dispersed nanofluids are prepared by milling of nanocomposite in ethylene glycol (EG) without using any surfactants/ dispersants. The resulting nanofluids have an excellent stability with no obvious sedimentation for at least three months. The results confirm the in-situ polymerization of EG on AlN surface and the formation of hyperbranched glycerol upon milling which in turn stabilizes the particles through a steric effect. The working nanofluids with very low loadings of up to 0.22 vol% of powder exhibit an enhanced heat transfer coefficient (h) of about 24% compared to that of the base fluid in a laminar flow regime (Re = 160). Brownian motion and boundary layer thinning are known as the main mechanisms, causing for this enhancement.  相似文献   
10.
近年来,我国高等教育呈现出快速发展的趋势,学生事务管理工作越来越复杂多样,对高校学生工作提出了系列新挑战。欧洲发达国家的高校学生事务管理体制社会化程度高、专业性强,对我们积极推进高校学生事务管理和服务工作具有十分有益的借鉴意义。本文主要就德、奥两国高校的学生事务管理机构一体化、后勤服务社会化、学生自主自治管理、就业指导和继续教育等情况进行了分析研究与本土化考量。  相似文献   
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