Multi-layered Complex Systems Research Articles

Epidemic process on partially overlapped multi-layer networks

The phenomenon of epidemic spread has received continuous attention due to its profound applications in a wide range of social and economic activities. In this paper we propose a partially overlapped multi-layer network model and illustrate the influence of multi-layer structure on outbreaks. Combined with the classic SIS model, we propose a set of discrete Markov equations and make first-order approximation on the threshold of epidemic outbreak. In comparison with independent simplex networks, we find that a multi-layer structure promotes epidemic spread and leads to a smaller critical threshold. In addition, we also find that the epidemic process on partially overlapped multi-layer networks is dominated by the layer with the largest main eigenvalue. Through Monte Carlo simulations, we find that the role of the dominant layer is irrelevant with its size, which means a small set of nodes can exhibit a disproportionate impact on the epidemics of a large network. Our research sheds light on the epidemic process on partially overlapped multi-layer complex systems, and provides a theoretical explanation of unexpected real-world outbreaks.

Microstructure characterizations, thermal analysis, and compression stress–strain behavior of lime-based plaster

• The impact of the water/cement ratio on the compressive strength of lime-based plaster is quantified. • A difference-based method for constructing target compressive strength is proposed. • Models of use to improve the prediction accuracy of the strength of lime-based plaster learning are proposed. • The stress–strain behavior of the cement models is possible using of Vipulanandan p–q model. • Predicting the compressive strength of the lime-based plaster as a function of w/c and age. Classical lime-based plasters (LP) are multilayer complex systems made of different fillers and binders; the behavior of LPs is determined by their physical properties: mutual connection, contact with the substrates, and external factors. Lime plaster is set to a solid mass that is durable and relatively flexible. It is permeable and allows for moisture diffusion and evaporation. It is less affected by water and will not dry or dissolve like clay or gypsum plaster. Plasters of hydrated lime are less brittle and less prone to breakage, which do not require expansion joints. Different plasters have been used in construction industries, such as cement, lime, mud, stucco, and gypsum plasters. Lime-based plaster (LP) is used as building insulation materials (Bims) against environmental impacts. Lime plaster is made of sand, water, and lime, usually non-hydraulic hydrated lime (also known as slaked lime, high calcium lime, or air lime). Ancient lime plaster often contained horse hair for reinforcement and pozzolanic additives to reduce work time. Microstructure tests such as X-ray fluorescence (XRF), energy dispersive X-ray (EDX), X-ray diffraction, scanning electron microscopy, and differential scanning calorimetry were used to identify the LP. Thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy, compressive strength, and modulus of elasticity. The XRF and EDX study revealed that the LP was mainly composed of SiO 2 and CaO, predominantly changed into calcium-silicate and CaCO 3 throughout the carbonation process. TGA results showed that the LP had high thermal stability up to 150 °C and 16.6 % weight loss at 1000 °C, proving the significant heat capacity of the material and fire resistance. The compressive strength of the LP with water to binder ratio (w/b) of 0.75 and 0.9 were 900 and 350 kPa at 28 days of curing, respectively. Three distinct mathematical models, including β, rational, and Vipulanandan p-q models, were proposed to predict stress–strain relationships of the LP. Based on the statistical parameters such as coefficient of determination (R 2 ), root mean square error (RMSE), and mean absolute error (MAE), the Vipulanandan p-q model was the best model for predicting the stress–strain behavior of the LP.

Babel: A Generic Benchmarking Platform for Big Data Architectures

In this era of big and fast data, software architects tend to find it really hard to make consistent decisions about which architecture and technologies are ideal for a certain business need. It is even harder to make them while dealing with the scarcity of clear methodologies, best practices and reference architectures. In this prospect, architecture evaluation through benchmarking can be of great interest, as it enables the detection of performance anomalies or bottlenecks as you go. The problem when talking about Big Data benchmarking, is that existing solutions remain technology-related, and do not deal with the heterogeneous aspect of complex architectures. In addition to that, businesses are in general dealing with multi-layered complex systems, involving various technologies, paradigms and micro-architectures. This means that the benchmarking solution must be able to give fine-grained insights about each of the layers. A successful benchmarking system must also be seamless, easy to use, scalable, and preferably cloud native. To satisfy these requirements, we designed and implemented Babel, a generic Big Data benchmarking platform, that insures an end-to-end performance evaluation and monitoring. We present in this paper the principles, architecture, integration and deployment steps of Babel.

Kac–Rice fixed point analysis for single- and multi-layered complex systems

We present a null model for single- and multi-layered complex systems constructed using homogeneous and isotropic random Gaussian maps. By means of a Kac–Rice formalism, we show that the mean number of fixed points can be calculated as the expectation of the absolute value of the characteristic polynomial for a product of independent Gaussian (Ginibre) matrices. Furthermore, using techniques from random matrix theory, we show that the high-dimensional limit of our system has a third-order phase transition between a phase with a single fixed point and a phase with exponentially many fixed points. This result is universal in the sense that it does not depend on finer details of the correlations for the random maps.

Network Aggregation Process in Multilayer Air Transportation Networks**Supported by the National Natural Science Foundation of China under Grant Nos 11405118, 11401448 and 11301403.

The air transportation network, one of the common multilayer complex systems, is composed of a collection of individual airlines, and each airline corresponds to a different layer. An important question is then how many airlines are really necessary to represent the optimal structure of a multilayer air transportation system. Here we take the Chinese air transportation network (CATN) as an example to explore the nature of multiplex systems through the procedure of network aggregation. Specifically, we propose a series of structural measures to characterize the CATN from the multilayered to the aggregated network level. We show how these measures evolve during the network aggregation process in which layers are gradually merged together and find that there is an evident structural transition that happened in the aggregated network with nine randomly chosen airlines merged, where the network features and construction cost of this network are almost equivalent to those of the present CATN with twenty-two airlines under this condition. These findings could shed some light on network structure optimization and management of the Chinese air transportation system.

A multi-analytical study of ancient Nubian detached mural paintings

A multi-analytical study was carried out on materials, techniques, and state of conservation of a set of detached Nubian mural paintings, originally belonging to the 10th century pictorial cycle of the church of Sonqi Tino, Sudan (70km south of the Egypt–Sudan border). These paintings represent one of the very few examples of Christian Nubian pictorial cycles preserved from the wide defacement experienced by these artifacts with the building up of the Aswan Dam. Non-invasive NMR depth profiling was used to preliminary study the hydrogen rich layers of the detached mural paintings. By this technique, it was possible to perform a virtual coring with a reconstruction of the complex series of layers that characterize the investigated artifacts. Then, micro-sampling and cross-section examination by SEM-EDX, micro-Raman, micro-FTIR, and 27Al and 29Si MAS NMR, allowed us to shed light on materials and technology exploited by the Medieval Nubian painters, with the identification of pigments and composition of the original primer, obtaining also information on layering of materials used by conservators during the detachment of the paintings and their transfer to a new support. The combination of preliminary non-invasive investigation with a set of micro-invasive analytical techniques allowed us to set up a protocol for a satisfactory decoding of the multilayered complex systems that characterize the detached paintings.