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51.
Extracting knowledge from big network traffic data is a matter of foremost importance for multiple purposes including trend analysis, network troubleshooting, capacity planning, network forensics, and traffic classification. An extremely useful approach to profile traffic is to extract and display to a network administrator the multi-dimensional hierarchical heavy hitters (HHHs) of a dataset. However, existing schemes for computing HHHs have several limitations: (1) they require significant computational resources; (2) they do not scale to high dimensional data; and (3) they are not easily extensible. In this paper, we introduce a fundamentally new approach for extracting HHHs based on generalized frequent item-set mining (FIM), which allows to process traffic data much more efficiently and scales to much higher dimensional data than present schemes. Based on generalized FIM, we build and thoroughly evaluate a traffic profiling system we call FaRNet. Our comparison with AutoFocus, which is the most related tool of similar nature, shows that FaRNet is up to three orders of magnitude faster. Finally, we describe experiences on how generalized FIM is useful in practice after using FaRNet operationally for several months in the NOC of GÉANT, the European backbone network.  相似文献   
52.
"昨天,这个城市还是以工厂为背景.今天将把它从黑色完全变为绿色.这个公园是真正意义上的城市化改造的一个重要元素."法国ILEX景观与城市规划设计公司董事长佩雷(PERE)先生在一次媒体采访中给出了对整个项目的定位.  相似文献   
53.
The use of renewable materials as barrier material is currently intensively investigated. Biopolymers such as polysaccharides, lipids, and proteins have been studied as barrier materials. Protein‐based films often possess good gas barrier properties, but because of their hydrophilic nature the gas barrier properties are sensitive to humidity. The improvement of the properties of sodium caseinate barrier films in potential packaging applications was studied by investigating the effects of enzymatic treatment and plasticizer on the film properties. Oxidoreductases Trametes hirsuta laccase (ThL) and Trichoderma reesei tyrosinase (TrTyr) were compared with transglutaminase for crosslinking of the sodium caseinate molecules in the films and coatings. All of the studied enzymes were able to crosslink sodium caseinate. Film solubility tests, protein electrophoresis, contact angle measurements, and atomic force microscopy studies showed that TrTyr treatment results in sodium caseinate films and coatings with better overall properties compared to treatment with ThL. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
54.
A significant proportion of people living with HIV (PLHIV) who successfully achieve virological suppression fail to recover CD4+ T-cell counts. Since adipose tissue has been discovered as a key immune organ, this study aimed to assess the role of adipokines in the HIV immunodiscordant response. This is a multicenter prospective study including 221 PLHIV starting the first antiretroviral therapy (ART) and classified according to baseline CD4+ T-cell counts/µL (controls > 200 cells/µL and cases ≤ 200 cells/µL). Immune failure recovery was considered when cases did not reach more than 250 CD4+ T cells/µL at 144 weeks (immunological nonresponders, INR). Circulating adipokine concentrations were longitudinally measured using enzyme-linked immunosorbent assays. At baseline, apelin receptor (APLNR) and zinc-alpha-2-glycoprotein (ZAG) concentrations were significantly lower in INRs than in immunological responders (p = 0.043 and p = 0.034), and they remained lower during all ART follow-up visits (p = 0.044 and p = 0.028 for APLNR, p = 0.038 and p = 0.010 for ZAG, at 48 and 144 weeks, respectively). ZAG levels positively correlated with retinol-binding protein 4 (RBP4) levels (p < 0.01), and low circulating RBP4 concentrations were related to a low CD4+ T-cell gain (p = 0.018 and p = 0.039 at 48 and 144 weeks, respectively). Multiple regression adjusted for clinical variables and adipokine concentrations confirmed both low APLNR and RBP4 as independent predictors for CD4+ T cells at 144 weeks (p < 0.001). In conclusion, low APLNR and RBP4 concentrations were associated with poor immune recovery in treated PLHIV and could be considered predictive biomarkers of a discordant immunological response.  相似文献   
55.
An efficient and space saving method for passive fire protection is the use of intumescent coatings, which swell when exposed to heat, forming an insulating char layer on top of the virgin coating. Although the temperature curves related to so-called cellulosic fires are often referred to as slow heating curves, special cases where the protective char is mechanically damaged and partly removed can cause extremely fast heating of the coating. This situation, for a solvent based intumescent coating, is simulated using direct insertion of free films into a muffle oven. The char formed is evaluated with respect to the mechanical resistance against compression, degree of expansion, and residual mass fraction. Experimental results show that when using this type of shock heating, the mechanical resistance of the char against compression cannot meaningfully be correlated to the expansion factor. In addition, char properties, measured at room temperature, were dependent on the preceding storage conditions (in air or in a desiccator). The char was found to have the highest mechanical strength against compression in the outer crust facing the heat source. For thin (147 μm) free coating films, a tendency to contract in the horizontal plane was observed. The experimental approach is relevant for testing of intumescent coatings used in buildings where moving or falling objects may damage the char during a fire.  相似文献   
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57.
The effect of different animal diets supplemented with linseed (source of omega‐3 fatty acids: n‐3) and/or conjugated linoleic acid (CON: control, LIN: 10% linseed, CLA: 2% conjugated linoleic acid, LINCLA: 10% linseed plus 2% CLA) on consumer liking of beef aged for 7 or 21 d was assessed in 3 Spanish cities. Overall, tenderness, juiciness, and flavor liking of beef were evaluated by consumers (n = 720) using 9‐point scales. Hedonic scores assigned by consumers did not differ (P > 0.05) for beef from animals fed the different diets and aged for 7 or 21 d. Consumer scores showed an increasing trend in beef liking with aging time. Consumers from Pamplona assigned lower (P < 0.05) hedonic scores for beef liking than consumers from Barcelona and Zaragoza. Linseed and/or CLA can be fed to improve the fatty acid profile in beef with minimal impact on consumer liking. Consumer ratings seem to depend on regional tastes and preferences.  相似文献   
58.
Pd-based membranes have been prepared by Pd electroless deposition on porous stainless steel substrate and their structure, composition, morphology and thickness were analyzed by X-ray diffraction (XRD), EDS and scanning electronic microscopy (SEM). The performance of these membranes as hydrogen diffusion electrodes was evaluated in a three-electrode cell in alkaline medium. The activity towards hydrogen oxidation was high at the beginning of the experiment, but it significantly decreased with time. The major cause of this phenomenon has been attributed to the slow entry of hydrogen at the H2/Pd interface. Even so, the technical feasibility of using these membranes as gas diffusion electrodes (GDE) has been proven.  相似文献   
59.
This paper provides an overview of the trends of the Spanish solar PV feed-in tariff (FIT) and its design elements, identifies some implications for the effective and cost-efficient deployment of solar PV in Spain and infers some lessons which might be useful for the implementation of support for solar PV elsewhere. Our analysis is based on a throughout revision of the relevant legislation, official data on deployment and related expenditure, informal discussions with key stakeholders and written documents. Several key design elements within FITs that should be implemented and other elements that should be avoided in order to have an effective and cost-efficient promotion of solar PV are identified. All in all, the specific design elements to be included are clearly contingent upon the preferences and priorities of policymakers.  相似文献   
60.
Three different NIR equipment were evaluated based on their ability to predict superficial water activity (a(w)) and moisture content in two types of fermented sausages (with and without moulds on surface), using partial least squares (PLS) regression models. The instruments differed mainly in wavelength range, resolution and measurement configuration. The most accurate equipment was used in a new experiment to achieve robust models in sausages with different salt contents and submitted to different drying conditions. The models developed showed determination coefficients (R(2)(P)) values of 0.990, 0.910 and 0.984, and RMSEP values of 1.560%, 0.220% and 0.007% for moisture, salt and a(w) respectively. It was demonstrated that NIR spectroscopy could be a suitable non-destructive method for on-line monitoring and control of the drying process in fermented sausages.  相似文献   
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