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211.
Karin Lindsjö 《Norsk geografisk tidsskrift. Norwegian journal of geography》2018,72(4):234-247
The purpose of the article is to discuss the term ‘quality’ in relation to primary education in Tanzania, and to contextualize quality and identify the premises for obtaining quality in primary school education in rural and urban settings. To understand opinions about the quality of education and the current situation in primary schools, the author conducted interviews with teachers and focus group discussions with parents and caregivers in Iringa town and three villages in Iringa Region. The findings indicate a general consensus, regardless of geographical setting, that quality in primary education is primarily measurable through national exams. However, surrounding circumstances such as infrastructure and poverty have a great impact on the quality of education in rural primary schools. Lack of water and electricity, and poor transport networks have consequences for schooling by limiting children’s, parents’, and teachers’ access to school supplies and limiting the ability of officials to carry out monitoring activities. The author concludes that the premises for providing and receiving education vary to a great extent, depending on geographical setting, and favour urban youths with respect to their further education. 相似文献
212.
Claudia Sandig Uta Sauer Karin Bräuer Ulrich Serfling Claudia Schütze 《Environmental Earth Sciences》2014,72(5):1421-1434
Our study at this natural analog site contributes to the evaluation of methods within a hierarchical monitoring concept suited for the control of CO2 degassing. It supports the development of an effective monitoring concept for geological CO2 storage sites—carbon capture and storage as one of the pillars of the European climate change efforts. This study presents results of comprehensive investigations along a 500-m long profile within the Hartou?ov (Czech Republic) natural CO2 degassing site and gives structural information about the subsurface and interaction processes in relation to parameters measured. Measurements of CO2 concentrations and investigation of the subsurface using electrical resistivity tomography and self-potential methods provide information about subsurface properties. For their successful application it is necessary to take seasonal variations (e.g., soil moisture, temperature, meteorological conditions) into consideration due to their influence on these parameters. Locations of high CO2 concentration in shallow depths are related to positive self-potential anomalies, low soil moistures and high resistivity distributions, as well as high δ13C values and increased radon concentrations. CO2 ascends from deep geological sources via preferential pathways and accumulates in coarser sediments. Repetition of measurements (which includes the effects of seasonal variations) revealed similar trends and allows us to identify a clear, prominent zone of anomalous values. Coarser unconsolidated sedimentary layers are beneficial for the accumulation of CO2 gas. The distribution of such shallow geological structures needs to be considered as a significant environmental risk potential whenever sudden degassing of large gas volumes occurs. 相似文献
213.
Economics of climate policy and collective decision making 总被引:1,自引:0,他引:1
Beat Bürgenmeier Andrea Baranzini Catherine Ferrier Céline Germond-Duret Karin Ingold Sylvain Perret Peter Rafaj Socrates Kypreos Alexander Wokaun 《Climatic change》2006,79(1-2):143-162
This paper explores the reasons why economic instruments of climate change are reluctantly applied and stresses the need for interdisciplinary research linking economic theory and empirical testing to deliberative political procedures. It is divided in three parts. The first one recalls the main issues in implementing Cost-Benefit Analysis such as information problems, uncertainties, discounting the future and irreversibilities. The second part shows how these issues can be treated in integrated assessment and techno-economic models and presents a case study, which shows that
- The chosen scenario tends to stabilize atmospheric CO2 concentration at around 550 ppm in the long run.
- Exclusion of possibility to trade CO2 emission permits under a cap regime would increase the cost of emission abatement for OECD countries.
- Combining different flexibility instruments might lead to significant gains in the overall cost of climate policy.
214.
Karin Mossberg Sonnek Tomas Mårtensson Ester Veibäck Peter Tunved Håkan Grahn Pontus von Schoenberg Niklas Brännström Anders Bucht 《Natural Hazards》2017,88(3):1565-1590
In this study, we analyse and discuss the possible impacts on the Swedish society of a volcanic eruption on Iceland, emitting ash particles and large quantities of sulphur dioxide. A scenario was developed, based on the historical Laki eruption of 1783–1784, to describe the content of a potential sulphur fog over time in Sweden. Due to its high complexity and the many uncertainties in the underpinning scientific data, the scenario was developed using a cross-disciplinary approach incorporating experts from different scientific fields. An analysis of the impacts of the hazard on human health, environment and technical equipment was then performed and, finally, representatives from national authorities assessed the overall societal challenges in responding to the consequences of a massive volcanic eruption. The analysis shows that it is the peak concentrations of sulphur dioxide and sulphuric acid rather than the longer periods of moderate concentrations that contribute most to the negative consequences for human health and environment. Altogether, three societal challenges were identified: the ability to compile and disseminate relevant information fast enough, to perform continuous measurements of concentrations of different substances in affected areas and to meet the large demand for medical care. 相似文献
215.
Gert Finger Frank Eisenhauer Reinhard Genzel Christopher Mandla Ian Baker Domingo Alvarez Antonio Amorim Wolfgang Brandner Christophe Dupuy Casey Deen Derek Ives Leander Mehrgan Manfred Meyer Karin Perraut Guy Perrin Jörg Stegmeier Christian Straubmeier Harald J. Weller Vincent Isgar 《Astronomische Nachrichten》2023,344(8-9):e20230069
Near-infrared adaptive optics as well as fringe tracking for coherent beam combination in optical interferometry require the development of high-speed sensors. Because of the high speed, a large analog bandwidth is required. The short exposure times result in small signal levels which require noiseless detection. Both requirements cannot be met by state-of-the-art conventional CMOS technology of near-infrared arrays as has been attempted previously. A total of five near-infrared SAPHIRA 320 × 256 pixel HgCdTe e−APD arrays have been deployed in the wavefront sensors and in the fringe tracker of the VLTI instrument GRAVITY. The current limiting magnitude for coherent exposures with GRAVITY is mk = 19, which is made possible with ADP technology. New avalanche photo-diode array (APD) developments since GRAVITY include the extension of the spectral sensitivity to the wavelength range from 0.8 to 2.5 μm. After GRAVITY a larger format array with 512 × 512 pixels has been developed for both AO applications at the ELT and for long integration times. Since dark currents of <10−3 e−/s have been demonstrated with 1Kx1K e−APD arrays and 2Kx2K e−APD arrays have already been developed, the possibilities and adaptations of e−APD technology to provide noiseless large-format science-grade arrays for long integration times are also discussed. 相似文献