Computer Communication & Collaboration

ISSN:2292-1028 (Print) ISSN:2292-1036(Online)

Vol. 5, Issue 2 (2017.05)

Editorial Board of CCC

Articles

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1. The Network Complexity of Small-scale Software Systems [Download PDF]

Authors:

Dong Yan(Corresponding author), Junsheng Jin

Abstract:

Large-scale complex networks in information technology area have been shown to display a scale-free distribution and a small-world property. However, the network complexity of small-scale software systems are studied seldom. This paper focuses on collaborative relationships among custom classes in small-scale software systems to study their network complexity. It is found that small-scale software systems written in Java as networks follow a stretched exponential distribution by empirical analysis. But collaborative relationships among custom classes don't have a distinct small-world property. In addition, the scale of a realistic system has a minor influence on network complexity.

Keywords:

Small-scale Systems, Stretched Exponential Distribution, Small-world Property

2. "Universal" Fitting Function for Quantitative Description of Quasi-Reproducible Measurements [Download PDF]

Author:

Raoul R. Nigmatullin(Correspondence author), Wei Zhang, Renhuan Yang, Yaosheng Lu, Guido Maione

Abstract:

In this paper the authors are trying to justify the following statement: is there a general platform (it is defined as an intermediate model (IM)) for description of a wide class of quasi-reproducible (QR) experiments? Under QR experiments we understand the set of measurements when during a measurement cycle they can be varied significantly under the influence of uncontrollable factors. If this general platform exists then it facilities the analysis of experiments associated with properties of complex systems, when the "best-fit function" that follows from the microscopic model is absent. This platform will bring a certain profit for a competitive/alternative theory. If the fitting function obtained from the theory looks very complicated then it can be expressed in terms of the IM and the parameters of this IM are expressed in terms of the generalized Prony spectrum. The physical meaning of the Fourier transform that used as the fitting function is explained also. It corresponds to an "ideal experiment" when all measurements during the experimental cycle are fully identical to each other. The new formulae for elimination of the apparatus functions are suggested. They help to evaluate the influence of uncontrollable factors and at certain conditions reduce the measured data to an "ideal experiment". As a nontrivial example we consider the fit of the single heartbeat (HB) recorded from anonymous persons. We took the ECG data from the reliable Internet resource PhysioNet Bank (http://physionet.org/cgi-bin/atm/ATM). The obtained results of its nontrivial application demonstrate its effectiveness in quantitative description of the ECG data in the frame of the suggested theory. We do hope that the quantitative description of the single heartbeat will find an application in the modern cardiology.

Keywords:

General Theory of the QR measurements, Intermediate Model, The Generalized Prony Spectrum, The Functional Least Square Method, The Fit of the Single Heartbeat

3. New routing metrics in QoS network [Download PDF]

Author:

Ting Lu(Correspondence author), Guohua Liu, Wenjing Guo

Abstract:

Providing end-to-end quality-of-service (QoS) guarantees is important in packet networks. The key issue is how to determine the feasible path that satisfies a lot of QoS constraints. In order to improve the service performance for real-time multimedia applications, we propose two new routing metrics (i.e., hop and bandwidth) in constraint-based path selection (CP). In this paper, we study the path selection under two QoS constraints. One is additive (delay), the other one is concave (bandwidth). We compare the performance of hop-bandwidth-based path selection (HBP) with that of delay-bandwidth-based path selection (DBP), which is the most usually used in CP. Besides analytical results, we run simulations to demonstrate the efficiency of the proposed routing algorithm. Simulation results show that HBP provides not only low end-to-end transmission delay but also low network cost.

Keywords:

QoS, Path Selection, Hop; Delay, Bandwidth