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81.
The aim of this work is to produce a simplified vegetation map of ice-free areas of the Fildes Peninsula (FP) and Ardley Island (AI) thought object-oriented classification using a QuickBird satellite image and to evaluate the influence of the global solar radiation (GSR) over the vegetation distribution. The vegetation data were generated from multiresolution segmentation using the panchromatic and infrared layers, and for the classification we calculated the normalized vegetative difference index (NVDI) and the green NVDI. Two classes were created – Lichen and Moss Cushion SubFormation and Moss Subformation – with 48 vegetation samples collected on surveys during the austral summers of 2008 and 2009. We used a kappa index to evaluate the classification efficiency using 100 sampled points obtained in austral summer of 2013. The GSR was estimated, and in order to evaluate the effect of meteorological phenomena and cloudless, we measured the GSR using a net radiometer model CNR4 installed in FP between 2014 and 2016. The estimate of GSR was done for seasons of 2015, in order to estimate the light compensation point and the saturation point for the plant communities in FP and AI. The kappa index was 0.73 and the global accuracy was 0.78, showing consistency between the classification and ground truth. The area was covered by vegetation in FP was 16.7% and in AI is 59.1%. The vegetation cover is distributed differently at FP and AI, and our results suggest GSR plays an important role in vegetation distribution and these tendencies could be related to greater GSR demand by mosses when compared to lichens.  相似文献   
82.
The hollow clay brick is the typical building unit that is employed not only over the whole Greece but also in many other Mediterranean countries. Nevertheless, its design is completely empirical. In this study, the design of the hollow clay brick is analyzed by employing a finite element package. To carry out this analysis, the thermal conductivity of the solid clay is measured by the transient hot-wire technique. As a consequence of the analysis, an improvement of 24 % in the design of the hollow clay brick is proposed.  相似文献   
83.
Conjugated alpha linolenic acid (CLNA) isomers are promising lipids owing to their similarities with conjugated linoleic acid (CLA) but exerting their bioactivity at lower doses; some isomers also belong to omega 3 family. This review aims to summarize the state of the art about the utilization of CLNA as a functional ingredient. Indeed, in vitro and in vivo studies reported that CLNA exerted anticancer, anti-inflammatory, anti-obese, and antioxidant activities. However, CLNA has not been tested in humans. These compounds are naturally present in meat and milk fat from ruminants but the highest concentrations are found in vegetable oils. Their incorporation in foodstuffs is one of the most effective strategies to elaborate CLNA-enriched products together with the microbiological production. Lactobacilli, propionibacteria, and bifidobacteria strains have been assayed to produce CLNA isomers but at the current moment there are not high CLNA concentration products elaborated using these strains. Furthermore, it is known that CLNA isomers are highly prone to oxidation when compared with linoleic acid and CLA, but the possible effects of elaboration and storage on high CLNA productsare unknown.The utilization of CLNA as a functional compound still remains a challenge and requires more research to address all of its technological and bioactivity aspects.  相似文献   
84.
The aim of the present study was to investigate the volatile fraction and discriminate 34 commercial thyme honeys from Morocco, Egypt, Spain, and Greece according to geographical origin, using key volatile compounds in combination with chemometrics. Sixty-two volatile compounds belonging to different classes were identified and semi-quantified using headspace solid phase micro-extraction coupled to gas chromatography/mass spectrometry (HS-SPME-GC/MS). Applying chemometric analyses to 17 volatiles (p < 0.05), honeys were successfully discriminated according to geographical origin. Correct classification rate was 88.2% using the cross-validation method. Volatile compounds proved to be a powerful tool for discriminating commercial thyme honeys from different countries.  相似文献   
85.
86.
Abstract: The article presents renovation solutions for orthotropic steel bridge decks consisting of bonding a second steel plate to the existing steel deck in order to reduce the stresses and enlarge the life span of the orthotropic bridge deck. Two solutions for the interface layer between the existing deck plate and the second steel plate are presented: thin epoxy (bonded system) and thick polyurethane (sandwich system). A parametric study based on analytical solutions is carried out on flexural behavior of beams representing the renovation solutions. The influence of geometrical, mechanical and structural parameters on the stiffness and stress reduction factor of the system is studied. Maximum values of stiffness and stress reduction are achieved when maximizing the interface layer thickness and minimizing the second steel plate thickness with in certain practical limits. Based on the weight restrictions one can choose the most efficient interface layer regarding thickness and mechanical properties.  相似文献   
87.
88.

Homebuyers are now demanding green buildings over conventional buildings due to better performance, higher operating savings, and the premium satisfaction that the green buildings offer. However, whilst the supply of green buildings is increasing, the satisfaction of the occupants requires evaluation. This research investigated the satisfaction of the occupants of certified residential green buildings in the Greater Kuala Lumpur. The research was based on a cross-sectional survey questionnaire comprising 15 performance factors and 118 green building occupants. The survey forms were administered through hand delivery. The satisfaction of the occupants with respect to the ability of the buildings to accommodate the elderly and the disabled was very high. The occupants were also satisfied with the acoustics, overall lighting, layout, and overall air quality of the buildings. The factor analysis structured the performance factors into four clusters, namely, lighting, indoor environmental quality, operating cost, and spatial. The findings will be useful for the design teams because developers and city planners and the green rating certifiers and facilitators make their decisions on the prioritisation of the performance criteria of the green buildings. Whilst the data were collected in Malaysia, the information is applicable to beyond Malaysia.

  相似文献   
89.
Brewer’s spent grain (BSG) was evaluated for its potential as a functional baking ingredient. Scanning electron microscopy (SEM) was used to examine the microstructure of BSG and wheat flours. Baked snacks (breadsticks) were prepared using 15%, 25% and 35% BSG and evaluated for their baking quality and fibre and protein content (over a period of 3 months). The addition of BSG altered the baking characteristics of the breadsticks by affecting their structure and texture. The snacks appeared to lack in cellular structure and crispiness. However, they had quite a stable shelf‐life, as changes in texture, moisture and aw progressed at a low rate. Addition of 25% and 35% BSG significantly increased the protein content of the snacks, and addition of 15% BSG more than doubled the content of dietary fibre in the samples.  相似文献   
90.
Reactive nanoscale multilayer foils for use in joining techniques have attracted a great deal of attention. A common feature of these nanolayers is the large amount of heat released during the reaction between the layers to form a new phase. In this study, films of alternated Ni and Al nanolayers (NanoFoil® made by the Indium Corporation) with period (bilayer thickness) close to 54 nm and with a thickness of 60 μm were used as local heat sources to bond lightweight alloys. The as-deposited Ni and Al alternated nanolayers evolve into NiAl nanometric grains when the multilayer, ignited by an electrical discharge, reacts. Joining of lightweight alloys was performed at room temperature under pressures of 10-80 MPa. The ability of the nanolayers to join these alloys by high temperature diffusion bonding was also investigated. The microstructural and chemical characterizations of the interfaces were performed on cross-sections of the joints by scanning electron microscopy and energy dispersive x-ray spectroscopy. Ni/Al nanolayers are an effective means of joining titanium alloys at room temperature. A sound interface, mainly composed by NiAl grains, is obtained in joints of TiAl/TiAl and TiAl/Inconel, produced with NanoFoil® by annealing at 700 ºC, during 60 min under a pressure of 10 MPa. The low shear strength revealed a weak adhesion of the nanofoil to the base materials.  相似文献   
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