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21.
Szymkowski Maciej Jasiński Piotr Saeed Khalid 《Innovations in Systems and Software Engineering》2021,17(3):309-317
Innovations in Systems and Software Engineering - One of the most important modules of computer systems is the one that is responsible for user safety. It was proven that simple passwords and... 相似文献
22.
ZhiBo Yang XueFeng Chen Maciej Radzienski Pawel Kudela Wieslaw Ostachowicz Yong Xie 《中国科学:技术科学(英文版)》2017,60(10):1505-1517
The continuous wavelet transform (CWT) is one of the crucial damage identification tools in the vibration-based damage assessment. Because of the vanishing moment property, the CWT method is capable of featuring damage singularity in the higher scales, and separating the global trends and noise progressively. In the classical investigations about this issue, the localization property of the CWT is usually deemed as the most critical point. The abundant information provided by the scale-domain information and the corresponding effectiveness are, however, neglected to some extent. Ultimately, this neglect restricts the sufficient application of the CWT method in damage localization, especially in noisy conditions. In order to address this problem, the wavelet correlation operator is introduced into the CWT damage detection method as a post-processing. By means of the correlations among different scales, the proposed operator suppresses noise, cancels global trends, and intensifies the damage features for various mode shapes. The proposed method is demonstrated numerically with emphasis on characterizing damage in noisy environments, where the wavelet scale Teager-Kaiser energy operator is taken as the benchmark method for comparison. Experimental validations are conducted based on the benchmark data from composite beam specimens measured by a scanning laser vibrometer. Numerical and experimental validations/comparisons present that the introduction of wavelet correlation operator is effective for damage localization in noisy conditions. 相似文献
23.
This paper presents the results of studies of wall effects in commercial soap-based greases LT4-S2 and HUTPLEX EP-2, thickened with, respectively, lithium 12-hydroxystearate and overbased calcium sulfonate. The studies were conducted in the presence of five different materials: copper alloy C11000, bronze B476, EPDM rubber and PTFE and PU thermoplastics. The influence of the energy state of the surface layer of the adsorbents and temperature (ranging from ?20 to 60 °C) on the intensity of wall effects was investigated. Changes in the structural viscosity and shear stress in the boundary layer area in the greases and the soap-based thickener’s ability to adsorb on the surfaces of the adsorbents were determined by evaluating the rheological parameter plateau modulus. 相似文献
24.
Jędrzej M. Marszałkowski Maciej Drozdowski Jakub Marszałkowski 《Journal of Grid Computing》2016,14(1):153-170
In this paper we analyze the impact of memory hierarchies on time-energy trade-off in parallel computations. Contemporary computing systems have deep memory hierarchies with significantly different speeds and power consumptions. This results in nonlinear phenomena in the processing time and energy usage emerging when the size of the computation is growing. In this paper the nonlinear dependence of the time and energy on the size of the solved problem is formalized and verified using measurements in practical computer systems. Then it is applied to formulate a problem of minimum time and minimum energy scheduling parallel processing of divisible loads. Divisible load theory is a scheduling and performance model of data-parallel applications. Mathematical programming is exploited to solve the scheduling problem. A trade-off between energy and schedule length is analyzed and again nonlinear relationships between these two criteria are observed. Further performance analysis reveals that energy consumption and schedule length are ruled by a complex interplay between the costs and speeds of on-core and out-of-core computations, communication delays, and activating new machines. 相似文献
25.
We propose a finite structural translation of possibly recursive π-calculus terms into Petri nets. This is achieved by using high-level nets together with an equivalence on markings in order to model entering into recursive calls, which do not need to be guarded. We view a computing system as consisting of a main program (π-calculus term) together with procedure declarations (recursive definitions of π-calculus identifiers). The control structure of these components is represented using disjoint high-level Petri nets, one for the main program and one for each of the procedure declarations. The program is executed once, while each procedure can be invoked several times (even concurrently), each such invocation being uniquely identified by structured tokens which correspond to the sequence of recursive calls along the execution path leading to that invocation. 相似文献
26.
While the experimental detection of entanglement provides already quite a difficult task, experimental quantification of entanglement is even more challenging, and has not yet been studied thoroughly. In this paper we discuss several issues concerning bounds on concurrence measurable collectively on copies of a given quantum state. Firstly, we concentrate on the recent bound on concurrence by (Mintert and Buchleitner in Phys Rev Lett 98:140505/1–140505/4, 2007). Relating it to the reduction criterion for separability we provide yet another proof of the bound and point out some possibilities following from the proof which could lead to improvement of the bound. Then, relating concurrence to the generalized robustness of entanglement, we provide a method allowing for construction of lower bounds on concurrence from any positive map (not only the reduction one). All these quantities can be measured as mean values of some two-copy observables. In this sense the method generalizes the Mintert–Buchleitner bound and recovers it when the reduction map is used. As a particular case we investigate the bound obtained from the transposition map. Interestingly, comparison with MB bound performed on the class of ${4\otimes 4}While the experimental detection of entanglement provides already quite a difficult task, experimental quantification of entanglement
is even more challenging, and has not yet been studied thoroughly. In this paper we discuss several issues concerning bounds
on concurrence measurable collectively on copies of a given quantum state. Firstly, we concentrate on the recent bound on
concurrence by (Mintert and Buchleitner in Phys Rev Lett 98:140505/1–140505/4, 2007). Relating it to the reduction criterion
for separability we provide yet another proof of the bound and point out some possibilities following from the proof which
could lead to improvement of the bound. Then, relating concurrence to the generalized robustness of entanglement, we provide
a method allowing for construction of lower bounds on concurrence from any positive map (not only the reduction one). All
these quantities can be measured as mean values of some two-copy observables. In this sense the method generalizes the Mintert–Buchleitner
bound and recovers it when the reduction map is used. As a particular case we investigate the bound obtained from the transposition
map. Interestingly, comparison with MB bound performed on the class of 4?4{4\otimes 4} rotationally invariant states shows that the new bound is positive in regions in which the MB bound gives zero. Finally,
we provide measurable upper bounds on the whole class of concurrences. 相似文献
27.
Yixuan Jia Christoph A. Spiegel Alexander Welle Stefan Heißler Elaheh Sedghamiz Modan Liu Wolfgang Wenzel Maximilian Hackner Joachim P. Spatz Manuel Tsotsalas Eva Blasco 《Advanced functional materials》2023,33(39):2207826
Manufacturing programmable materials, whose mechanical properties can be adapted on demand, is highly desired for their application in areas ranging from robotics, to biomedicine, or microfluidics. Herein, the inclusion of dynamic and living bonds, such as alkoxyamines, in a printable formulation suitable for two-photon 3D laser printing is exploited. On one hand, taking advantage of the dynamic covalent character of alkoxyamines, the nitroxide exchange reaction is investigated. As a consequence, a reduction of the Young´s Modulus by 50%, is measured by nanoindentation. On the other hand, due to its “living” characteristic, the chain extension becomes possible via nitroxide mediated polymerization. In particular, living nitroxide mediated polymerization of styrene results not only in a dramatic increase of the volume (≈8 times) of the 3D printed microstructure but also an increase of the Young's Modulus by two orders of magnitude (from 14 MPa to 2.7 GPa), while maintaining the shape including fine structural details. Thus, the approach introduces a new dimension by enabling to create microstructures with dynamically tunable size and mechanical properties. 相似文献
28.
In this report we present for the first time strong evidence for autosomal-dominant inheritance of grant liver hemangiomas. Furthermore, we review the current literature about incidence, pathogenesis, clinics, as well as diagnostic and therapeutic aspects of LH. A large family of Italian origin is described where three female patients in three successive generations suffered from large symptomatic LH. In addition, two other female relatives exhibited asymptomatic LH on sonographic scans. The restriction of the disease to the female gender could be explained by a sex-dependent difference in penetrance or expressivity of a presumable "liver-hemangioma" gene, or by known proliferative factors such as female sex hormones. We also observed an increased incidence of adenomas of the thyroidea among members with or without LH of the presented family. This uncommon familial association has also not yet been described and its genetic aspects are discussed. 相似文献
29.
Sphingolipid metabolism and cell growth regulation 总被引:2,自引:0,他引:2
30.