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Complexity Analysis of Unsaturated Flow in Heterogeneous Media Using a Complex Network Approach  [PDF]
Hamed. O. Ghaffari,Mamdou Fall,Erman. Evgin
Physics , 2009,
Abstract: In this study, we investigate the complexity of two-phase flow (air/water) in a heterogeneous soil sample by using complex network theory, where the supposed porous media is non-deformable media, under the time-dependent gas pressure. Based on the different similarity measurements (i.e., correlation, Euclidean metrics) over the emerged patterns from the evolution of saturation of non-wetting phase of a multi-heterogeneous soil sample, the emerged complex networks are recognized. Understanding of the properties of complex networks (such degree distribution, mean path length, clustering coefficient) can be supposed as a way to analysis of variation of saturation profiles structures (as the solution of finite element method on the coupled PDEs) where complexity is coming from the changeable connection and links between assumed nodes. Also, the path of evolution of the supposed system will be illustrated on the state space of networks either in correlation and Euclidean measurements. The results of analysis showed in a closed system the designed complex networks approach to small world network where the mean path length and clustering coefficient are low and high, respectively. As another result, the evolution of macro -states of system (such mean velocity of air or pressure) can be scaled with characteristics of structure complexity of saturation. In other part, we tried to find a phase transition criterion based on the variation of non-wetting phase velocity profiles over a network which had been constructed over correlation distance.
Complexity Analysis of Pipeline Mapping Problems in Distributed Heterogeneous Networks
Yi Gu,Qishi Wu,Mengxia Zhu,Nageswara S. V. Rao
International Journal of Distributed Sensor Networks , 2009, DOI: 10.1080/15501320802498372
Abstract: Largescale scientific applications require using various system resources to execute complex computing pipelines in distributed networks to support collaborative research. System resources are typically shared in the Internet or over dedicated connections based on their location, availability, capability, and capacity. Optimizing the network performance of computing pipelines in such distributed environments is critical to the success of these applications.
Dragutin Kermek,Neven Vr?ek,Tomislav Jakupi?
Journal of Information and Organizational Sciences , 2006,
Abstract: The paper investigates the design of heterogeneous distributed system for foreign exchange portfolio analysis. The proposed model includes few separated and dislocated but connected parts through distributed mechanisms. Making system distributed brings new perspectives to performance busting where software based load balancer gets very important role. Desired system should spread over multiple, heterogeneous platforms in order to fulfil open platform goal. Building such a model incorporates different patterns from GOF design patterns, business patterns, J2EE patterns, integration patterns, enterprise patterns, distributed design patterns to Web services patterns. The authors try to find as much as possible appropriate patterns for planned tasks in order to capture best modelling and programming practices.
Complexity Analysis in Cyclic Tag System Emulated by Rule 110  [PDF]
Shigeru Ninagawa,Genaro J. Martínez
Computer Science , 2013,
Abstract: It is known that elementary cellular automaton rule 110 is capable of supporting universal computation by emulating cyclic tag system. Since the whole information necessary to perform computation is stored in the configuration, it is reasonable to investigate the complexity of configuration for the analysis of computing process. In this research we employed Lempel-Ziv complexity as a measure of complexity and calculated it during the evolution of emulating cyclic tag system by rule 110. As a result, we observed the stepwise decline of complexity during the evolution. That is caused by the transformation from table data to moving data and the elimination of table data by a rejector.
Computational Analysis of Performance for Heterogeneous Integrated System with Test Automation
K Krishna Mohan,A Srividya,Ravikumar Gedela,

国际自动化与计算杂志 , 2007,
Abstract: Heterogeneity is inevitable in enterprises due to their various input requirements.The usage of proprietary integration products results in the increased cost of enterprises.During the integration,the focus area has been found to often address only the functional requirements,while the non-functional requirements are side-stepped during the initial stages of a project.Moreover, the use of proprietary integration products and non-standards-based integration platform has given rise to an inflexible integration infrastructure resulting in adaptability concerns.Web services-based integration,based on open standards,is deemed to be the only feasible solution in such cases.This paper explains the performance analysis of enterprise integration in heterogeneous environments for the distributed and the transactional applications.The analysis presented in this paper is seen as a step towards making intelligent decisions well in advance when choosing the integration mechanism/products to address the functional as well as the non-functional requirements considering the future integration needs.
BIOZON: a system for unification, management and analysis of heterogeneous biological data
Aaron Birkland, Golan Yona
BMC Bioinformatics , 2006, DOI: 10.1186/1471-2105-7-70
Abstract: Here we present a system (Biozon) that addresses these problems, and offers biologists a new knowledge resource to navigate through and explore. Biozon unifies multiple biological databases consisting of a variety of data types (such as DNA sequences, proteins, interactions and cellular pathways). It is fundamentally different from previous efforts as it uses a single extensive and tightly connected graph schema wrapped with hierarchical ontology of documents and relations. Beyond warehousing existing data, Biozon computes and stores novel derived data, such as similarity relationships and functional predictions. The integration of similarity data allows propagation of knowledge through inference and fuzzy searches. Sophisticated methods of query that span multiple data types were implemented and first-of-a-kind biological ranking systems were explored and integrated.The Biozon system is an extensive knowledge resource of heterogeneous biological data. Currently, it holds more than 100 million biological documents and 6.5 billion relations between them. The database is accessible through an advanced web interface that supports complex queries, "fuzzy" searches, data materialization and more, online at http://biozon.org webcite.High throughput technologies such as microarrays and mass spectrometry, as well as fast sequencing techniques produce biological data at an ever increasing rate. The sheer volume of new data exposes new processes and complex phenomena in biological systems. Consequently, the focus is shifting from exploring single molecules to complexes of molecules or pathways involving multiple proteins and other subcellular agents. Often, the study of one entity is tightly coupled to the study of other, related entities. For example, by studying individual proteins we wish to better understand their role in cellular processes, and by studying cellular processes, we hope to better understand cellular "computations", and to gain insight into the functions of
Novel measures based on the Kolmogorov complexity for use in complex system behavior studies and time series analysis  [PDF]
Dragutin T. Mihailovic,Gordan Mimic,Emilija Nikolic-Djoric,Ilija Arsenic
Physics , 2013,
Abstract: We have proposed novel measures based on the Kolmogorov complexity for use in complex system behavior studies and time series analysis. We have considered background of the Kolmogorov complexity and also we have discussed meaning of the physical as well as other complexities. To get better insights into the complexity of complex systems and time series analysis we have introduced the three novel measures based on the Kolmogorov complexity: (i) the Kolmogorov complexity spectrum, (ii) the Kolmogorov complexity spectrum highest value and (iii) the overall Kolmogorov complexity. The characteristics of these measures have been tested using a generalized logistic equation. Finally, the proposed measures have been applied on different time series originating from: the model output (the biochemical substance exchange in a multi-cell system), four different geophysical phenomena (dynamics of: river flow, long term precipitation, indoor 222Rn concentration and UV radiation dose) and economy (stock prices dynamics). Results which are obtained offer deeper insights into complexity of the system dynamics behavior and time series analysis when the proposed complexity measures are applied.
Hybrid Full-/Half-Duplex System Analysis in Heterogeneous Wireless Networks  [PDF]
Jemin Lee,Tony Q. S. Quek
Mathematics , 2014,
Abstract: Full-duplex (FD) radio has been introduced for bidirectional communications on the same temporal and spectral resources so as to maximize spectral efficiency. In this paper, motivated by the recent advances in FD radios, we provide a foundation for hybrid-duplex heterogeneous networks (HDHNs), composed of multi-tier networks with a mixture of access points (APs), operating either in bidirectional FD mode or downlink half-duplex (HD) mode. Specifically, we characterize the net- work interference from FD-mode cells, and derive the HDHN throughput by accounting for AP spatial density, self-interference cancellation (IC) capability, and transmission power of APs and users. By quantifying the HDHN throughput, we present the effect of network parameters and the self-IC capability on the HDHN throughput, and show the superiority of FD mode for larger AP densities (i.e., larger network interference and shorter communication distance) or higher self-IC capability. Furthermore, our results show operating all APs in FD or HD achieves higher throughput compared to the mixture of two mode APs in each tier network, and introducing hybrid-duplex for different tier networks improves the heterogenous network throughput.
Social Influence as a Voting System: a Complexity Analysis of Parameters and Properties  [PDF]
Xavier Molinero,Fabián Riquelme,Maria Serna
Computer Science , 2012,
Abstract: We consider a simple and altruistic multiagent system in which the agents are eager to perform a collective task but where their real engagement depends on the willingness to perform the task of other influential agents. We model this scenario by an influence game, a cooperative simple game in which a team (or coalition) of players succeeds if it is able to convince enough agents to participate in the task (to vote in favor of a decision). We take the linear threshold model as the influence model. We show first the expressiveness of influence games showing that they capture the class of simple games. Then we characterize the computational complexity of various problems on influence games, including measures (length and width), values (Shapley-Shubik and Banzhaf) and properties (of teams and players). Finally, we analyze those problems for some particular extremal cases, with respect to the propagation of influence, showing tighter complexity characterizations.
Heterogeneous Cellular Networks Using Wireless Backhaul: Fast Admission Control and Large System Analysis  [PDF]
Jian Zhao,Tony Q. S. Quek,Zhongding Lei
Computer Science , 2015,
Abstract: We consider a heterogeneous cellular network with densely underlaid small cell access points (SAPs). Wireless backhaul provides the data connection from the core network to SAPs. To serve as many SAPs and their corresponding users as possible with guaranteed data rates, admission control of SAPs needs to be performed in wireless backhaul. Such a problem involves joint design of transmit beamformers, power control, and selection of SAPs. In order to tackle such a difficult problem, we apply $\ell_1$-relaxation and propose an iterative algorithm for the $\ell_1$-relaxed problem. The selection of SAPs is made based on the outputs of the iterative algorithm. This algorithm is fast and enjoys low complexity for small-to-medium sized systems. However, its solution depends on the actual channel state information, and resuming the algorithm for each new channel realization may be unrealistic for large systems. Therefore, we make use of random matrix theory and also propose an iterative algorithm for large systems. Such a large system iterative algorithm produces asymptotically optimum solution for the $\ell_1$-relaxed problem, which only requires large-scale channel coefficients irrespective of the actual channel realization. Near optimum results are achieved by our proposed algorithms in simulations.
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