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1.
This paper proposes a reading of the cultural and social aspects associated with sundry notions of territory through Spanish photography at the end of the twentieth century and the beginning of the twenty-first. An analysis of a series of case studies reveals a new awareness of the common space through the concept of trace, being understood beyond the material imprint, as it falls under the influence of the cultural aspects that clarify the account of the conflict and consciousness of the suburbs and peripheries. Contemporary ruins arising from unbridled urban growth, or the invisible wounds associated with certain places, converge in a series of images that have their own tradition in the conceptual experiments of the 70s and the aesthetics of the “non-site” displayed in the 90s. As background, the economic and political avatars of recent years in Spain – also linked to a global crisis – are manifested in a series of photographic musings whose images portray the scenarios of a premature ruin linked to property speculation and the traces of a collective memory. 相似文献
2.
ABSTRACTExtreme natural events require effective emergency procedures to minimize adverse effects on a region’s population and economy. Such procedures typically involve the effort of several different teams of first responders (e.g., fire fighters, public administrations, police departments, utility companies), hence coordination is fundamental to the effectiveness of the response to the emergency that must be supported with adequate infrastructures. Nonetheless, first responders often rely on manual processes, in the life cycle of extreme events, which do not change consistently with the type of shock or affected population. The aim of this paper is to present a technology transfer process to improve both the emergency alert process and the knowledge of disaster-type safety procedures through the implementation of a proposed platform. We also highlight a pilot application on a post-disaster case study—the province of L’Aquila (Abruzzi) in Italy. 相似文献
3.
Gregory D. DeYong 《国际生产研究杂志》2020,58(6):1776-1804
The newsvendor problem is a staple of operations management research, pedagogy and practice. From its humble roots as a single-period problem for a price-taking newspaper seller, this problem (and its solutions) has inspired generations of researchers and students while contributing to inventory management at countless firms. One major extension of the newsvendor problem was the extension of the decision variables to include price as well as quantity. This extension has been known for decades, but recently gained new life, as researchers have expended considerable energy in analysing and exploring this scenario. We trace major developments in the single-period, price- and quantity-setting newsvendor problem in the recent past and propose extensions of these developments. We also extend a relatively unexplored model describing a price-setting newsvendor faced with a fixed stock level to show that there is a unique optimising price and that, as in the price- and quantity-setting newsvendor problem, the optimal price depends heavily on the form of the demand uncertainty. 相似文献
4.
María C. Ruiz Iván González Valerio Rodriguez Rafael Padilla 《Mineral Processing and Extractive Metallurgy Review》2021,42(1):1-8
ABSTRACT The effect of chloride ions on the copper extraction equilibria, the rate of extraction, copper/iron selectivity, and chloride extraction was studied for organic phases containing pure ketoxime (LIX 84-IC) and pure nonylaldoxime (LIX 860N-IC). In these systems, the used aqueous phase contained total chloride concentrations from 0 to 110 g/l. It was determined that the chloride ions in the aqueous solution had a large negative effect on the extraction equilibria for LIX 84-IC and a small effect for LIX 860N-IC. This deleterious effect is attributed to an increase in the hydrogen ion activity coefficient in the presence of chloride ions. The chloride accelerated the rate of copper extraction even though the reaction was fast in all the tested conditions. An increase in the temperature from 25°C to 35°C affected positively the extraction equilibria for LIX 84-IC. 相似文献
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Rheological Properties and Characteristics of Hydraulic Transportation and Heat-Mass Exchange of Coal-Water Fuels 总被引:4,自引:0,他引:4
A. P. Burdukov V. V. Konovalov V. I. Popov V. D. Fedosenko 《Journal of Mining Science》2002,38(3):220-228
The procedure is proposed for calculating the characteristics of flow and heat exchange of coal-water fuels as applied to the pipeline hydraulic transport and heat-mass exchange in the apparatus of ecologically clean combustion in the objects of power engineering. 相似文献
8.
为了解释和查明N2TEC浮选法的基本原理,本文报道了在用戊基钾黄药(PAX)作捕收剂时,黄铁矿的低电位疏水状态的研究成果。新制定的N2TEC浮选法的目的是提高难处理含金硫化矿金回收率。在典型的N2TEC浮选法中,用氮气代替空气作为浮选气体,戊基钾黄药作为评选含金黄铁矿颗粒的捕收剂。l997年3月,第一个N2TEC浮选工艺在内华达州Lone Tree矿山浮选厂投产,一直操作至今。根据电化学校制接触角测量结果,研究了黄铁矿的低电位、低pH疏水状态与浮选变量(pH、气相组成、捕收剂浓度和黄铁矿电位)之间的关系。 相似文献
9.
The performance of laboratory scale methanol-degrading biofilters packed with lava rock was checked during almost 1 yr under different conditions. The biomass concentration and biomass adaptation of the inoculum dramatically affected the start-up and the performance of the systems during the first stages of operation. A fast start-up was obtained when using concentrated and adapted inocula, while diluted or non-adapted inocula proved to be much less efficient. The performance of the reactor during long-term operation was significantly affected by the toxic load and moisture content of the gas. Critical loads between 120 and 280 g/m(3)h were reached during different phases of the study. The reactor had a high stability to EBRT changes when working at values between 48.0 and 91.1s, showing little or no negative effect when decreasing the EBRT. Hardly any difference was observed regarding performance when using either a downflow or upflow feed, although slightly better results were obtained when working in a downflow mode. 相似文献
10.
ABSTRACTIn most of the present day buses, the main problem that causes discomfort to the passengers sitting in the rear seats is that the seats are not maintained at the same level from the ground when the rear wheels of the bus encounter obstacles like speed breakers or pits. To overcome this problem, we have designed an MEMS-based Electro-hydraulic system. This articles aims at to give the overview of the MEMS-based Electro-hydraulic system. 相似文献