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51.
This paper considers methods for knowledge exploitation in security policies for Service-Oriented Architecture (SOA) environments, discovering the modality conflicts in particular. Two algorithms for discovering SOA-specific modality conflicts are proposed. First, a trivial (ad-hoc) approach is presented and further extended by the improved algorithm which offers lower time complexity. The formal verification of the proposal is followed by experimental results confirming the expected supremacy of the improved algorithm. 相似文献
52.
R-22的替代现状 总被引:9,自引:2,他引:9
张建君 《制冷与空调(北京)》2005,5(1):62-69
1背景 R~22于1928年最初被人们所认可,并于1936年开始商业化生产使用.迄今为止,R-22已经在很多系统中得到应用,从最小型的窗式空调到最大型的冷水机组和热泵,也包括那些区域性的冷却和加热系统.使用这种通用型制冷剂的单个设备的制冷功率在2 kW与30 MW之间(0.5冷吨到9,500冷吨).R-22的使用装置包括:旋转式活塞、往复式活塞、涡旋式、螺杆和离心式压缩机,在实验中还包括吸收循环装置.没有一种制冷剂能够像R-22这样有如此大的产量和如此广的应用范围. 相似文献
53.
Verleger Rolf; Ja?kowski Piotr; Aydemir Ayta?; van der Lubbe Rob H. J.; Groen Margriet 《Canadian Metallurgical Quarterly》2004,133(4):494
In general, both consciously and unconsciously perceived stimuli facilitate responses to following similar stimuli. However, masked arrows delay responses to following arrows. This inverse priming has been ascribed to inhibition of premature motor activation, more recently even to special processing of nonconsciously perceived material. Here, inverse priming depended on particular masks, was insensitive to contextual requirements for increased inhibition, and was constant across response speeds. Putative signs of motor inhibition in the electroencephalogram may as well reflect activation of the opposite response. Consequently, rather than profiting from inhibition of primed responses, the alternative response is directly primed by perceptual interactions of primes and masks. Thus there is no need to assume separate pathways for nonconscious and conscious processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
Piotr Szwed Pawel Skrzynski Wojciech Chmiel 《Multimedia Tools and Applications》2016,75(17):10667-10690
For various IT systems security is considered a key quality factor. In particular, it might be crucial for video surveillance systems, as their goal is to provide continuous protection of critical infrastructure and other facilities. Risk assessment is an important activity in security management; it aims at identifying assets, threats and vulnerabilities, analysis of implemented countermeasures and their effectiveness in mitigating risks. This paper discusses an application of a new risk assessment method, in which risk calculation is based on Fuzzy Cognitive Maps (FCMs) to a complex automated video surveillance system. FCMs are used to capture dependencies between assets and FCM based reasoning is applied to aggregate risks assigned to lower-level assets (e.g. cameras, hardware, software modules, communications, people) to such high level assets as services, maintained data and processes. Lessons learned indicate, that the proposed method is an efficient and low-cost approach, giving instantaneous feedback and enabling reasoning on effectiveness of security system. 相似文献
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Tomasz Pdzinski Katarzyna Grzyb Konrad Skotnicki Piotr Filipiak Krzysztof Bobrowski Chryssostomos Chatgilialoglu Bronislaw Marciniak 《International journal of molecular sciences》2021,22(9)
Within the reactive oxygen species (ROS) generated by cellular metabolisms, hydroxyl radicals (HO•) play an important role, being the most aggressive towards biomolecules. The reactions of HO• with methionine residues (Met) in peptides and proteins have been intensively studied, but some fundamental aspects remain unsolved. In the present study we examined the biomimetic model made of Ac-Met-OMe, as the simplest model peptide backbone, and of HO• generated by ionizing radiation in aqueous solutions under anoxic conditions. We performed the identification and quantification of transient species by pulse radiolysis and of final products by LC-MS and high-resolution MS/MS after γ-radiolysis. By parallel photochemical experiments, using 3-carboxybenzophenone (CB) triplet with the model peptide, we compared the outcomes in terms of short-lived intermediates and stable product identification. The result is a detailed mechanistic scheme of Met oxidation by HO•, and by CB triplets allowed for assigning transient species to the pathways of products formation. 相似文献
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Emilia Szymańska Katarzyna Winnicka Piotr Wieczorek Pawe? Tomasz Sacha El?bieta Anna Tryniszewska 《International journal of molecular sciences》2014,15(10):17765-17777
The combination of an antifungal agent and drug carrier with adjunctive antimicrobial properties represents novel strategy of complex therapy in pharmaceutical technology. The goal of this study was to investigate the unmodified and ion cross-linked chitosan’s influence on anti-Candida activity of clotrimazole used as a model drug in hydrogels. It was particularly crucial to explore whether the chitosans’ structure modification by β-glycerophosphate altered its antifungal properties. Antifungal studies (performed by plate diffusion method according to CLSI reference protocol) revealed that hydrogels obtained with chitosan/β-glycerophosphate displayed lower anti-Candida effect, probably as a result of weakened polycationic properties of chitosan in the presence of ion cross-linker. Designed chitosan hydrogels with clotrimazole were found to be more efficient against tested Candida strains and showed more favorable drug release profile compared to commercially available product. These observations indicate that novel chitosan formulations may be considered as promising semi-solid delivery system of clotrimazole. 相似文献
59.
Piotr Grabowski 《International journal of control》2013,86(3):1033-1053
As shown in Grabowski (1983), the problem of evaluation of the quadratic performance index for delay-differential systems of neutral type can be effectively solved by the use of Lyapunov functionals. In this paper another solution to that problem, based on the frequency-domain approach, is proposed. With the use of Plancherel's theorem and other tools of complex analysis, this task is reduced to a Riemann-Hilbert problem, an explicit solution to which is found by elementary methods. Our results can be regarded as a generalization of those due to Walton and Marshall (1984, 1987). Two simple examples of application are also provided. 相似文献
60.
Jérémy Lebon Guénhaël Le Quilliec Piotr Breitkopf Rajan Filomeno Coelho Pierre Villon 《International Journal of Material Forming》2014,7(3):275-287
In this study, we show that stochastic analysis of metal forming process requires both a high precision and low cost numerical models in order to take into account very small perturbations on inputs (physical as well as process parameters) and to allow for numerous repeated analysis in a reasonable time. To this end, an original semi-analytical model dedicated to plain strain deep drawing based on a Bending-Under-Tension numerical model (B-U-T model) is used to accurately predict the influence of small random perturbations around a nominal solution estimated with a full scale Finite Element Model (FEM). We introduce a custom sparse variant of the Polynomial Chaos Expansion (PCE) to model the propagation of uncertainties through this model at low computational cost. Next, we apply this methodology to the deep drawing process of U-shaped metal sheet considering up to 8 random variables. 相似文献