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The reliability Studies are done in order to determine the probability of functioning or availability of different engineering systems. These studies can also provide a basis for comparing different structures of a system and can be used as a tool to improve the system design. Also, reliability is an important consideration in the planning, design and operation of transit system. Since the issue of the reliability of electric vehicles has not been sufficiently and seriously evaluated yet, so in this paper, the reliability of the various types of these kinds of vehicles will be discussed and then the reliability indices of them will be compared with each other and with the conventional cars  

In this investigation, the stability analysis of a rotating elastic stepped shaft is studied and the sufficient condition for system stability in the sense of Lyapunov is derived. The model consists of an elastic stepped shaft which is clamped rigidly to a rotary device. From the model's point of view, the entire length of shaft is partitioned into uniform segments with different characteristics. The Lyapunov direct method is applied in this survey where the Hamilton function has been chosen as the candidate Lyapunov function. Since the dynamical mode shapes of the shaft are required for the stability analysis, the shaft has been modeled by the Euler- Bernoulli beam theory and the... 

This paper presents a new fault injection approach, which is based on a co-operation between a simulator and an emulator. This hybrid approach utilizes the advantages of both simulation-based fault injection as well as physical fault injection to provide a good controllability, observability and also a high speed in the fault injection experiments. To do this, parts of a circuit are simulated while the rest pans of the circuit are emulated. A fault injection tool called FITSEC (Fault Injection Tool based on Simulation and Emulation Co-operation) is developed, which supports the entire process of a system design. This is based on both Verilog and VHDL languages and can be used to inject... 

Knowledge of Air-water two phase flows is significant to different engineering systems such as chemical reactors and power plant and petrochemical and petroleum industry. One of the most industrial cases of two phase flow is two phase flow in vertical large pipes. In this paper in order to find two phase flow behavior along vertical large diameter pipes we simulate air inlets with different number of holes and different hole diameters in the same flow rate of air. In addition, flow characteristics such as cross-sectional void fraction and velocity and pressure were considered. To achieve this aim, main equations of flow have been developed for investigation of flow behavior in air-water two... 

This paper proposes for wind turbines (WTs) an analytical reliability method, used on other engineering systems, to compare the reliability of different turbine concepts. The main focus of the paper is to compare the reliability of geared generator and direct-drive concept WTs. Modification methods are also recommended for improving the availability of WTs and geared generator concept incorporating doubly fed induction generator  

During the past decade, Electro-Hydraulic system has performed a significant role in industrial engineering as an actuator for high performance and precision positioning applications. In this case, many control methods have been developed for an electro-hydraulic actuated clutch. In this paper a Linear Quadratic Regulators (LQR) is proposed to trajectory control of a wet clutch actuated by a hydraulic servo valve mechanism. Simulation study was performed using linearized mathematical model of the system implemented in MATLAB software. Based on the simulation results performance of the proposed controller was evaluated and discussed  

Applying engineering approaches to non-engineering systems such as biological systems has brought a new research filed to the surface. The sole purpose of this research is mathematical modeling the cell cycle control system in the fissionyeast cell using Ordinary Differential Equations (ODE).This paper, in fact, introduces the capabilities of engineering knowledge and engineering of control, in particular, in this field. ©2009 IEEE  

The use of advanced cycles to take advantage of the gas turbine's thermodynamic characteristics has received increasing attention in recent years. These cycles have been developed for large scale power generation. Due to the powerful abilities of bio-inspired computing techniques such as Genetic Algorithm in locating the optimal (or near optimal) solutions to a given optimization problem, they are widely utilized for determining the parameters of different engineering systems in order to meet the specified performance objectives for a given problem. In order to illustrate the performance of one of these techniques, development and application of it for an engineering problem is presented. In... 

In this paper, a new approach to control continuous time chaotic systems with an unknown governing equation and limitation on the measurement of states, has been investigated. In many chaotic systems, disability to measure all of the states is a usual limitation, like in some economical, biological and many other engineering systems. Takens showed that a chaotic attractor has an astonishing feature in which it can embed to a mathematically similar attractor by using time series of one of the states. The new embedded attractor saves much information from the original attractor. This phenomenon has been deployed to present a new way to control continuous time chaotic systems, when only one of... 

This paper describes a novel adaptive out-of-step detection algorithm based on dissimilar measurement approaches. Two superimposed measurements enable the algorithm to detect fast as well as slow power swings. Both methods recognize power swings right from the beginning of the swing impedance movement. The first principle is based on continuous rate-of-change measurement of the traveling swing impedance. The second method continuously monitors the speed and the shape of the swing impedance trajectory. The algorithm detects extremely high swing frequencies of up to 7 Hz and maintains functionality under single-pole open conditions, i.e. auto-reclose dead time. The associated distance relay... 

As a direct consequence of power systems restructuring on one hand and unprecedented renewable energy utilization on the other, the uncertainties of power systems are getting more and more attention. This fact intensifies the difficulty of decision making in the power system context; therefore, the uncertainty analysis of the system performance seems necessary. Generally, uncertainties in any engineering system study can be represented probabilistically or possibilistically. When sufficient historical data of the system variables is not available, a probability density function (PDF) might not be defined, they must be represented in another manner i.e. using possibilistic theory. When some... 

Although more than half a century is passed since space technology was first developed, developing countries are just beginning to enter the arena, focusing mainly on educating professionals. Space technology by itself is an interdisciplinary science, is costly, and developing at a fast pace. Moreover, a fruitful education system needs to remain dynamic if the quality of education is the main concern, making it a complicated system. This paper makes use of the System Engineering Approach and the experiences of developed countries in this area while incorporating the needs of the developing countries to devise a comprehensive program in space engineering at the Master's level. The needs of... 

Since the development of data centers, power management (i.e., assessment, consumption and monitoring) has been a great challenge among scientists and engineers. By emerging a new generation of data center in the form of Hyperscale cloud data centers (HCDC), this concern has become more devastating than ever. The huge physical scale and the high level of system utilization through large power compensating system are some of the main characteristics of today's HCDC. The lack of appropriate power assessment from available power estimation models, prevents professionals from designing an accurate HCDCcapacity planning. In particular, during steady state workload processing at the high... 

In this study, a three-dimensional tablet-like porous scaffold, comprising core-shell fibers to host proteins inside the core, was developed. The fabrication method involved the novel combination of coaxial and wet electrospinning in a single setting. Poly (ε-caprolactone) was chosen as the based polymer and bovine serum albumin was used as a model protein. These 3D tablet-like scaffolds exhibited adequate porosity and suitable pore size for cell culture and cell infiltration, in addition to appropriate mechanical properties for cartilage tissue engineering. The effects of different parameters on the behavior of the system have been studied and the 3D scaffold based on the core-shell fiber... 

This paper presents a solution to the boundary stabilization of a FGM plate in free transverse vibration. The composite laminated plate dynamics is presented by a linear forth order partial differential equation (PDE). A linear control law is constructed to stabilize the plate. The control force consists of feedback of the velocity at the boundaries of plate. The novelty of this article is that it is possible to stabilize asymptotically a free transversely vibrating composite plate with simply supported or clamped boundary condition via boundary control without resorting to truncation of the model. © 2008 IEEE  

Analogous to Computer-Aided Software Engineering (CASE), which aims to facilitate Software Engineering through specialized tools, Computer-Aided Method Engineering (CAME) strives to support a wide range of activities carried out by method engineers. Although there is consensus on the importance of tool support in method engineering, existing CAME environments are incomplete prototypes, each covering just a few steps of the method engineering process. This paper summarizes the history and the state of the practice in CAME technology, and provides criteria-based critique on existing CAME environments, thus highlighting their strengths and weaknesses. © 2008 Springer-Verlag Berlin Heidelberg  

In this paper we propose a neuro-fuzzy architecture for Web content taxonomy using hybrid of Adaptive Resonance Theory (ART) neural networks and fuzzy logic concept. The search engine called Kavosh1 is equipped with unsupervised neural networks for dynamic data clustering. This model was designed for retrieving images without metadata and in estimating resemblance of multimedia documents; however, in this work only text mining method is implemented. Results show noticeable average precision and recall over search results. © 2007 IEEE