Abstract: This article proposes an algorithm for prognosis in optimal analysis of manufacturing systems. Uncertain knowledge of such task requires for specific reasoning and adaptive model base of fuzzy logic analyzes. The proposed method performs the interfaces between the results provided by the fuzzy supervision model and the algorithm witch identify the real state of the monitored system. The supervisory system sends failure signals described in a fuzzy approach. These ones represent inputs values in the system of failure optimal analysis which identifies the current degradation states by recurrent identification cycle. The proposed algorithm has also predictive component capable to determine the possible evolution of the system state towards a critical state of failure.

Keywords: fuzzy logic, prognostic, optimal analysis, manufacturing system 

Abstract: The mechanism that classical routing protocols use to transmit routing updates and to maintain adjacency can be susceptible to packets loss and to bandwidth limitation. We propose a new method for transmitting routing information and hello information which can assure delivery even if the links are lossy or their capacity is limited. This method is adapted to IPv6 packets and, with the implementation of a routing algorithm, it builds the routing tables.

Keywords: networking, IPv6, routing, stability, bandwidth.

 A. Filipescu, E. Minca, A. Filipescu Jr., G. Petrea: Modeling and Control of Assembly/Disassembly Mechatronic Line Served by Robotic Manipulator Mounted on Mobile Platform 

Abstract: The new idea of this paper is to make reversible an assembly mechatronic line, i.e. to allow complete disassembly, by using a mobile platform equipped with robotic manipulator. The approach is a hybrid one, in which the assembly/disassembly line is the discrete system while the wheeled mobile robot (WMR) together with the robotic manipulator (RM) is considered the continuous one. The mobile platform is used only in disassembling operations, in order to transport the components from the disassembling locations to the storage locations. Therefore, Synchronized Hybrid Petri Nets (SHPN) approach is used in modeling and control. This hybrid system takes into consideration the distribution of the necessary tasks to perform the hybrid disassembly of the components, using robot synchronization with flexible line process. The ultimate goal is to make completely reversible the assembly line. The SHPN model is transposed into LabView platform, such as to get a control structure of the mechatronic line and of WMR.

Keywords: Hybrid Petri Nets; robotic manipulators; flexible manufacturing systems; mobile robots.

Abstract: In power electronics area, the PLL (Phase Lock Loop) circuit is needed to reconstruct the sinusoidal reference signal used on the APF (active power filters) or grid-tied inverters, starting from the distorted grid voltage. Research area of the APF focuses more on the current of voltage control loops and less on the sinusoidal reference signal, usually considered available by default. Implementing in practice such a circuit poses difficulties since the available PLL integrated circuits are designed for digital telecommunication area, where signals are digital and a small phase error is acceptable. This paper presents a phase lock loop model with harmonic output and zero phase error during normal use.

Keywords: PLL, sinusoidal output, grid synchronization, distorted input signal.

L. F. Barbulescu, V. Minzu: Designing a Modular Simulator for a Navigation Lock  

Abstract: When building a simulator for an industrial installation, a divide and conquer approach can have very good results. This means that the original installation is divided into smaller components which are simulated independently and then interconnected to obtain the final product. This paper presents the steps required for designing such a modular simulator for a navigation lock that allows the operators to view and control all phases of operation.

Keywords: distributed systems, navigation lock, modular simulators, dynamic systems, discrete event simulation.

A. V. Diaconu: Multiple Bitstreams Generation Using Chaotic Sequences

Abstract: This article presents a method to transform a chaotic sequence of real numbers into multiple bitstreams, using multi-level discretization. Although the original intent was to achieve a higher/multiple flow of bits, much faster (i.e. in terms of computational time), it was subsequently conjugated with the one of preserving statistical properties of newly formed bitstreams (i.e. to have the ability of keeping their recommendations for usage within secure cryptographic application and not only, e.g. stochastic computing and/or generation of simulation data for the study of traffic in networks, whether they are WSNs, ATM or Telecoms). Thus, CrypTool, VRA and NIST battery of statistical tests were used in order to present an analysis of the randomness of the bitstreams obtained by applying the proposed discretization method. Theoretical and practical arguments, rounded by good statistical results, confirm viability of the proposed method and recommend it in generation of multiple bitstreams that will be used for secure cryptographic applications.

Keywords: chaotic dynamical system, randomness testing, multi-level discretization, VRA, NIST.

Abstract: This paper investigates the opportunity of using a numerical procedure for computing the renewal parameters of an equipment. The reasons of this approach reside in the sampled way we measure the process variables and the possibility of on-line parameter computation, for both the renewal and the reliability models. The computation algorithm is presented, then the errors with respect to an analytical procedure are evaluated, considering a validation example. The paper shows that the errors of the sampled model are negligible, within the average operating time, with respect to a continuous model. The same property applies to the comparison with a hybrid model (continuous for the process model and sampled for the renewal model), so we conclude that numerical evaluation of the reliability and renewal parameters is possible and preferable.

Keywords: reliability, Markov model, renewal process, numerical procedures, preventive maintenance