مجله فناوری اطلاعات در طراحی مهندسی
سال سوم شماره 2 (زمستان 1389)

this paper a new approach for synchronization of heart pacemakers models with the aid of measure theory proposed. For the implementation of this method among the different kinds of cell models, Van der Pol model chose. This model is used for analysis of interaction between nonlinear coupled pacemakers of heart. If two oscillators are not synchronized blocking arrhythmia happens. Two kinds of arrhythmias (Blocking & ectopic) that cause unwanted interrupt in synchronization phenomena are modeled. In this paper the idea of using a mathematical method (measure theory) to solve an applied control problem is presented. The advantage of proposed method is that the control input is piecewise and synchronization happens in less than five seconds.

In the present paper the application of Dissolved Air Flotation (DAF) system for wastewater treatment, especially in the case of industrial effluent, by use of a pilot system has been investigated. It is for the first time in dissolved air flotation system that instead of air dissolving tube, hydro cyclone technology is used to dissolve air in water with ratio of 1:1 (almost 100%) in the form of small air bulbs by use of circular tank instead of rectangular tank. The advantage of usage of circular tank in DAF system is the capability of being treated in higher rate of mass, so less space is needed. Although application of hydro cyclone with different diameters of holes for producing mixing energy which also has the capability of direct injection of chemical coagulant and polymeric materials leads to the higher efficiency of treatment and so reduces the cost of pump and consumed air. Investigations on the efficiency of this system was done by providing and analyzing samples of wastewater treated and untreated with different polymers as coagulant, in this investigation the effect of PAC was considered too. Sampling and analyzing of them was done according to standard method. The results of the analyses show that pilot system has high efficiency, especially in the case of oil removal.

Flood Routing is a mathematical procedure for predicting the changing magnitude, speed, and shape of a flood wave as a function of time at one or more points along a watercourse. Flood routing procedures may be classified as either hydrological or hydraulics. Hydrological methods use the principle of continuity and a relationship between discharge and the temporary storage of excess volumes of water during the flood period. Hydraulic methods of routing involve the numerical solutions of the one dimensional Saint-Venant equations of gradually varied unsteady flow in open channels. In this research the examination of the preissman, lax, characteristics and muskingum-cunge methods in the Karoon River are provided with programming in MATLAB software. The results of various methods have been compared with using of statistical standards. It is desired for the paper to check the validity of these models for single- and multi-peak flood hydrographs. The results indicated that the studied methods generally provided reasonable output in comparison with the observed hydrographs.

In this paper, a non-linear carrier controller with an exponential carrier generator is design and simulated for power factor correction (PFC).then, this controller is applied to single phase and three phase rectifier using a boost regulator for PFC. the power factor and its variations are measured by computer simulation against the changes in various loads and switching frequencies and the results are discussed. In order to produce voltages lower than the input voltage, a PFC using a buck regulator is used in rectifiers. However, the buck type PFC produces lower power factor then the boost type. For this reason, a fly back regulator is used as a PFC to produce lower voltage then input voltage. Power factor obtained by computer simulation of Fly back PFC are acceptable and are above 95%.

A theoretical solution for thermo-elastic analysis of functionally graded (FG) rotating disk with variable thickness based on third-order shear deformation theory (TSDT) in large displacements is presented. Material properties and disk thickness profile are assumed to be represented by power law distributions and the variation of temperature is assumed to occur in the radial direction and by used Von Karman assumptions, equilibrium equations are obtained. DQM and Newton’s method used for solution equilibrium equations and displacement field obtain. Finally, Results of four kind of annular disks with constant thickness, linear, convex and concave curves accounted and the new results have been compared with deflections’ first-order deformation theory (FSDT) and other studies.

This paper has present geometrically nonlinear analysis a circular multilayer with piezoelectric layers. Composite plats considered orthotropic and piezoelectric strain is assumed that is change linearly while the voltage is applied and the most voltage creation is in the z direction. Plate react to electrical and mechanical load coincide. Governing equations obtained by von-Karman assumption for first and third shear deformation theory and solved by finite difference method and Results compared with other research.

This paper presents a framework for publishing Persian linked data. First, the steps of the framework are presented including selecting target data, publishing data as RDF and HTML, linking to LOD cloud and publishing void. In order to evaluate the proposed framework, the case study of publishing some academic data from Ferdowsi University of Mashhad of Mashhad is discussed. By analyzing the experimental results of the project and classifying the problems, some publisher-oriented recommendations are proposed to improve the quality of datasets on the web.

The distributed nature of developing ontologies, leads to heterogeneous ontologies which try to express the same domain. Ontology matching aims to find semantic correspondences between the entities belonging to different ontologies. Ontology matchers use different methods to find the correspondences. In this paper, we concentrate on lexical similarity. Different terms may be used for expressing the same concept. Matchers aim to find semantic correspondences between the names of entities using an external lexicon, e.g. Word Net. However, some drawbacks exist in using Word Net and the lexical phase of the well-known matchers still suffers from some shortcomings. In this paper, in addition to solve the problems using Word Net, we try to improve this phase using naming pattern techniques. Evaluation results show our improved lexical phase outperforms the ones of well-known matchers, including Prior+, ASMOV, and RiMOM with respect to the standard evaluation measurements.

This paper investigates the operation of the resonant-tunneling high electron mobility transistor (RTHEMT) and presents a novel sub-circuit model for simulating the RTHEMT in the SPICE simulator. Then, an innovative structure for two-input exclusive OR (XOR) gate based on the RTHEMT is introduced and characteristics of this gate are discussed. Details of design, input and output values and margins, delay of each transition, maximum operating frequency, static and dynamic power dissipation of new XOR gate is calculated using the RTHEMT model and discussed in detail.