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231.
Life cycle management (LCM) can be applied to the whole construction process, thus making it possible to improve sustainability indicators and also minimize the environmental loads of the full building life cycle. To illustrate this, a case study has been carried out based on the application of the LCM approach to a typical Spanish Mediterranean house located in Barcelona with a total area of 160 m2 and a projected 50-year life span, which has been modeled according to the Spanish building technical code (CTE). The aim of this research is to use sustainability indicators in the pre-construction and operation (use and maintenance) phases and also to promote and support the adoption of the LCM within the construction industry. This paper concludes that regarding the significant environmental issue of climate change, there was a total emission of 2.34E03 kg CO2-Eq/m2 per 50 years, of which about 90.5% was during the operation phase (use 88.9% and maintenance 1.7%) and the pre-construction phase account for a total of 9.5%. In terms of this dwelling's environmental loads, the operation phase is the most critical because of the high environmental loads from energy consumption for heating, ventilation and air conditioning (HVAC), lighting, electrical appliances and cooking. 相似文献
232.
Sara González-García Carles M. Gasol Xavier Gabarrell Joan Rieradevall Ma Teresa Moreira Gumersindo Feijoo 《Renewable Energy》2010,35(5):1014-1023
Liquid biofuels provide one of the few options for fossil fuel substitution in the short to medium-term and they are strongly being promoted by the European Union as transport fuel (such as ethanol) since they have the potential to offer both greenhouse gas (GHG) savings and energy security. A “well to wheel” analysis has been conducted for poplar based ethanol by means of the Life Cycle Assessment (LCA) approach. The aim of the analysis is to assess the environmental performance of three ethanol applications (E10, E85 and E100) in comparison with conventional gasoline. To compare the environmental profiles, the study addressed the impact potentials per kilometre driven by a middle size passenger car, taking into account the performance difference between ethanol blends and gasoline. According to the results of this study, fuel ethanol derived from poplar biomass may help to reduce the contributions to global warming, abiotic resources depletion and ozone layer depletion up to 62%, 72% and 36% respectively. Reductions of fossil fuel extraction of up to 80% could be achieved when pure ethanol is used. On the contrary, contributions to other impact categories would be increased, specifically to acidification and eutrophication. In both categories, ethanol based blends are less environmentally friendly than conventional gasoline due to the higher impact from the upstream activities. Research focussed on the reduction of the environmental impacts should be pointed forward poplar cultivation as well as ethanol conversion plant (enzyme manufacturing, energy production and distillation). In this study poplar cultivation was really intensive in order to obtain a high yield. Strategic planning according to the location of the crops and its requirements should help to reduce these impacts from its cultivation. 相似文献
233.
Journal of Computer Virology and Hacking Techniques - The number of malicious files detected every year are counted by millions. One of the main reasons for these high volumes of different files is... 相似文献
234.
D Gaillard R Bouvier C Scheiner C Nessmann AL Delezoide P Dechelotte B Leheup MP Cordier D Carles A Lallemand 《Canadian Metallurgical Quarterly》1996,16(1):25-40
A collaborative study was performed to determine the different types and mechanisms of intestinal abnormalities during gestation. Cases had to fulfill one or more of the following three criteria: (1) meconium ileus, (2) intestinal stenosis or atresia, and (3) meconium peritonitis. Esophageal atresia, anorectal atresia, and abdominal wall defects were excluded. One hundred two cases were reviewed from the autopsies of 42 induced abortions, 22 stillborns, and the surgical findings in 38 neonates. Meconium ileus was detected mainly during the second trimester (28/38), and was associated with cystic fibrosis (15), fetal blood deglutition (4), infection (6), or multiple-abnormalities (10), in which three chromosomal aberrations were found. Intestinal stenosis or atresia was more commonly detected during the third trimester of gestation (46/56). Sixteen of the 30 duodenal malformations were associated with trisomy 21, whereas in the 26 small intestinal atresias, signs of distress or ischemia were most frequently detected. Only 8 of 25 meconium peritonitis cases were isolated. A total of 20 cystic fibrosis cases could be proved. In this series, functional abnormalities were observed predominantly in the second trimester and associated mainly with cystic fibrosis or amniotic fluid abnormalities. Anatomic lesions were commonly detected later on and associated with ischemic conditions, chromosomal aberrations, and even cystic fibrosis. 相似文献
235.
Review on Computational Trust and Reputation Models 总被引:17,自引:1,他引:16
The scientific research in the area of computational mechanisms for trust and reputation in virtual societies is a recent discipline oriented to increase the reliability and performance of electronic communities. Computer science has moved from the paradigm of isolated machines to the paradigm of networks and distributed computing. Likewise, artificial intelligence is quickly moving from the paradigm of isolated and non-situated intelligence to the paradigm of situated, social and collective intelligence. The new paradigm of the so called intelligent or autonomous agents and multi-agent systems (MAS) together with the spectacular emergence of the information society technologies (specially reflected by the popularization of electronic commerce) are responsible for the increasing interest on trust and reputation mechanisms applied to electronic societies. This review wants to offer a panoramic view on current computational trust and reputation models. 相似文献
236.
P. Puech E. Daran G. Landa C. Fontaine P. S. Pizani R. Carles 《Microelectronics Journal》1995,26(8):789-795
Highly strained GaAs layers have been grown by molecular beam epitaxy on (100)-, (111)- or (112)-oriented Si or CaF2 substrates. The origin, sign, bisotropic nature, value, homogeneity and relaxation of the built-in strain have been studied by Raman spectroscopy. Specific measurements have been performed by using selection rules and line shape analysis over a wide temperature range. 相似文献
237.
Chuan Lu Andy Devos Johan A K Suykens Carles Arús Sabine Van Huffel 《IEEE transactions on information technology in biomedicine》2007,11(3):338-347
This paper investigates variable selection (VS) and classification for biomedical datasets with a small sample size and a very high input dimension. The sequential sparse Bayesian learning methods with linear bases are used as the basic VS algorithm. Selected variables are fed to the kernel-based probabilistic classifiers: Bayesian least squares support vector machines (BayLS-SVMs) and relevance vector machines (RVMs). We employ the bagging techniques for both VS and model building in order to improve the reliability of the selected variables and the predictive performance. This modeling strategy is applied to real-life medical classification problems, including two binary cancer diagnosis problems based on microarray data and a brain tumor multiclass classification problem using spectra acquired via magnetic resonance spectroscopy. The work is experimentally compared to other VS methods. It is shown that the use of bagging can improve the reliability and stability of both VS and model prediction. 相似文献
238.
Paul Valckenaers John Sauter Carles Sierra Juan Antonio Rodriguez-Aguilar 《Autonomous Agents and Multi-Agent Systems》2007,14(1):61-85
This paper addresses multi agent system (MAS) environments from an application perspective. It presents a structured view on environment-centric MAS applications. This comprises three base configurations, which MAS applications may apply directly or combine into a composite configuration. For each configuration, the paper presents key issues, requirements and opportunities (e.g. time management issues, real-world augmentation opportunities and state snapshot requirements). Thus, the paper delineates what environment technology may implement to serve MAS applications. Sample applications illustrate the configurations. Next, electronic institutions provide an example of an environment technology, addressing norms and laws in an agent society, already achieving some maturity. In comparison, application-domain specific environment technologies still are in embryonic stages. 相似文献
239.
Nuria Rojas Margarita Sánchez-Molina Gema Sevilla Ernesto Amores Eluxka Almandoz Joseba Esparza Marlon R. Cruz Vivas Carles Colominas 《International Journal of Hydrogen Energy》2021,46(51):25929-25943
Proton exchange membrane water electrolysis (PEMWE) is a promising technology to be incorporated in the production of green hydrogen, but one of its limitation to market penetration is the cost of bipolar plates (BPP).Aiming to reduce the cost of PEMWE stack, different surface engineered coating systems based on CrN/TiN, Ti/TiN, Ti and TiN deposited by physical vapor deposition on SS 316L, SS 904L and SS 321 were tested, as potential cost effective solutions to be implemented on bipolar plates. A corrosion evaluation has been carried out in anodic PEMWE conditions in order to determine the best substrate/coating combination for bipolar plates. Ti/TiN multi-layered coating on SS 321 shown the best performance with ?0.02% weight loss, current at 2 VSHE to 436 μA cm?2 and ICR after corrosion test to 9.9 mΩ cm2. 相似文献
240.
The Annals of Regional Science - The aim of this paper is to analyse common location patterns of software and video game (SVE) industry and the related agglomeration processes with other creative... 相似文献