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Mechanomyography (MMG) has become a promising method for pattern recognition in upper-limb prostheses because mechanical signals can overcome the inherited unreliable drawbacks of the bioelectric electromyography (EMG) and electroencephalogram (EEG). However, the existing multi-channel pattern recognition methods require multi-site MMG because it is difficult to extract enough useful features from a single-site MMG. Therefore, this paper proposes a multi-channel finger pattern recognition using a single-site MMG signal. First, multi-mode high-dimensional features are extracted from the MMG signals, including statistical features, frequency-domain features, and acoustic features; second, the extracted features are further used for the pattern recognition using artificial neural networks (ANNs). In this study, 14 participants, including 6 males (3 athletes, 3 non-athletes), 6 females (3 athletes, 3 non-athletes) and 2 male amputees (wrist amputation and unilateral transradial) participated in the experiments. The real-time results show that the mean classification accuracy was 95.1% with 2.6 standard deviations (SDs) over the test folds (male athletes), 89.9%, 88.6% with 3.1, 3.7 SD (male non-athletes and female athletes, respectively) and 77.6% and 74.4% with 9.3 and 11.4 SD, respectively (wrist amputation, unilateral transradial) for seven movements. The results show that the proposed method has the capability to individually control fingers.

This paper presents development of the spectral element method (SEM) for analysis of circular and annular circular plates vibration under impact load. A novel formulation is proposed in frequency domain for conducting spectral element matrix. Several numerical examples are presented in order to demonstrate performance of the presented method compared to other numerical methods in literature. The presented formulation was applied in order to analyze vibration of annular circular plates with various thicknesses and various internal-to-external radius ratios. In addition, annular circular plate displacements subjected to an impact load were calculated using the presented SEM.

This paper presents development of the spectral element method (SEM) for the vibration analysis of thin shallow shells with rectangular planform subjected to impact loads. Dynamic formulation was developed for a thin shallow shell with two opposite edges simply supported and the other two edges with arbitrary boundary conditions. The SEM for such a shell was formulated in the frequency domain. Comparison studies were performed to assess the performance of the presented method. The effect of boundary conditions of the shallow shells is discussed in this paper. Shallow shell displacement subjected to impact load was calculated using the presented SEM.

In this study, two new moment resisting connections of beams to precast concrete columns under lateral load were analyzed via application of nonlinear finite element analysis software ABAQUS 6.10. The precast connections considered were the beam-column connections in which precast beams is connected to continuous precast column with corbel using (i) inverted E (bolted connection) and (ii) box section (welded connection). Connection responses associated with lateral resistance, lateral stiffness, ductility, and energy dissipation were compared to a reference monolithic connection. Achieved lateral resistance, lateral stiffness and ductility of the proposed connections was approximately 98%, 80% and 80% of the equivalent monolithic connection, respectively. The effect of axial load on column and compressive strength of concrete on behavior of the connections were studied. The analytical results show that the performance of two proposed precast connections were close to the performance of corresponding monolithic connection.

This paper presents a novel hybrid method coupling artificial neural network (ANN) and simulated annealing (SA), called ANN/SA to predict the fraction of pyrite remaining and therefore the pyrite oxidation rate in the wastes at different depths of a coal washing pile in the Alborz Markazi Coalfield, in northeast Iran. Waste depth, oxygen mole fraction and initial pyrite content in the waste particles were used as inputs to the network. The output of the network was the amount of pyrite content remaining. An ANN/SA model with Levenberg-Marquardt algorithm and a 3-4-3-1 arrangement showed a great capability. The network was used to predict the pyrite content remaining at two trenches E and F over the study waste pile once it was trained with the field-measured data. Simulated results obtained by the ANN/SA model were very closer to the experimental data compared to the outputs of simple ANN and multivariable least squares regression methods. The correlation coefficient (R) value, by the ANN/SA model, was 0.999 for training set, and in testing stage it was 0.998 and 0.99957 for trench E and trench F respectively which shows the model prediction was quite satisfactory. The performance of the model on the training and testing data, mean squared error (MSE) and mean absolute percent error (MAPE), indicate that it has both good predictive ability and generalisation performance.

Summary In this study, hybrid models are designed to predict groundwater inflow to an advancing open pit mine and the hydraulic head (HH) in observation wells at different distances from the centre of the pit during its advance. Hybrid methods coupling artificial neural network (ANN) with genetic algorithm (GA) methods (ANN–GA), and simulated annealing (SA) methods (ANN–SA), were utilised. Ratios of depth of pit penetration in aquifer to aquifer thickness, pit bottom radius to its top radius, inverse of pit advance time and the HH in the observation wells to the distance of observation wells from the centre of the pit were used as inputs to the networks. To achieve the objective two hybrid models consisting of ANN–GA and ANN–SA with 4-5-3-1 arrangement were designed. In addition, by switching the last argument of the input layer with the argument of the output layer of two earlier models, two new models were developed to predict the HH in the observation wells for the period of the mining process. The accuracy and reliability of models are verified by field data, results of a numerical finite element model using SEEP/W, outputs of simple ANNs and some well-known analytical solutions. Predicted results obtained by the hybrid methods are closer to the field data compared to the outputs of analytical and simple ANN models. Results show that despite the use of fewer and simpler parameters by the hybrid models, the ANN–GA and to some extent the ANN–SA have the ability to compete with the numerical models.

A dynamic model was developed for long-term simulation of a heavy duty gas turbine. The model includes the essential control algorithm of the gas turbine as well as the most common outputs and other important intermediate variables. Control algorithm details, such as wind up protection and load limiter algorithm which have large effect on gas turbine transient behavior, are included. The model parameters are identified by applying genetic algorithm and least squares algorithm on regular operational data from a real plant to better match the model response to the real plant. The simulation results have been validated with real plant data and shown to have valid accuracy for many engineering applications.

Recently, creating security in multimedia systems involving video has become one of the main needs in commercial and military usages. The most important traits of video frames are simultaneousness of frames and high volume of information. Considering these features, A5/1 and W7 stream ciphers are used for video main frames in the field of selective encryption of each DCT transform coefficient.In addition, a suitable method is expressed in order to select the encryption method of DCT transform coefficients by the stream algorithms. The simulation results of MATLAB software show that this method is suitable for multimedia security in terms of both security and execution speed of the algorithm.

In recent years, security of multimedia systems such as image and video has become one of the main needs in computer and communication networks. To encrypt multimedia content, lightweight and fast algorithms are usually used in frequency transform domain and in a partial encryption form, having time efficiency, high execution speed and correspondence with compression structures. In this article, a lightweight and fast algorithm is proposed and two designs in partial encryption scheme of DCT transform coefficients are introduced based on three fundamental principles and confrontation the partial encryption attacks (cryptographic attack, replacement attack and statistical model based attack). Moreover, the proposed algorithm is compared with A5/1 and W7 stream ciphers. The results of analyses and simulations by MATLAB software show that the proposed encryption algorithm and two introduced designs are applicable for real-time security applications of multimedia which require high-speed computations and sufficient security levels.

Single-shaft gas turbines are sensitive to frequency changes which might affect the grid stability during large frequency drops. This paper presents a new control system that uses steam injection as an auxiliary input to improve the transient performance of the gas turbine during frequency drops. Steam injection is beneficial because it reduces the peak temperature in the combustion chamber and augments the output power by increasing the mass flow through the turbine. The use of this auxiliary input is based on the event-based control approach. It means that during the frequency drop, the controller exploits the steam injection to help the main control loop recover the frequency and when the frequency reaches its predefined value, the system will return to its normal operation. The performance of the proposed control algorithm is investigated under different scenarios and the results show that the application of steam injection improves the performance of the regular control algorithm significantly, especially near full load condition.

The groundwater inflow into a mine during its life and after ceasing operations is one of the most important concerns of the mining industry. This paper presents a hydrogeological assessment of the Irankuh Zn-Pb mine at 20 km south of Esfahan and 1 km northeast of Abnil in west-Central Iran. During mine excavation, the upper impervious bed of a confined aquifer was broken and water at high-pressure flowed into an open pit mine associated with the Kolahdarvazeh deposit. The inflow rates were 6.7 and 1.4 m(3)/s at the maximum and minimum quantities, respectively. Permeability, storage coefficient, thickness and initial head of the fully saturated confined aquifer were 3.5 × 10(-4) m/s, 0.2, 30 m and 60 m, respectively. The hydraulic heads as a function of time were monitored at four observation wells in the vicinity of the pit over 19 weeks and at an observation well near a test well over 21 h. In addition, by measuring the rate of pumping out from the pit sump, at a constant head (usually equal to height of the pit floor), the real inflow rates to the pit were monitored. The main innovations of this work were to make comparison between numerical modelling using a finite element software called SEEP/W and actual data related to inflow and extend the applicability of the numerical model. This model was further used to estimate the hydraulic heads at the observation wells around the pit over 19 weeks during mining operations. Data from a pump-out test and observation wells were used for model calibration and verification. In order to evaluate the model efficiency, the modelling results of inflow quantity and hydraulic heads were compared to those from analytical solutions, as well as the field data. The mean percent error in relation to field data for the inflow quantity was 0.108. It varied between 1.16 and 1.46 for hydraulic head predictions, which are much lower values than the mean percent errors resulted from the analytical solutions (from 1.8 to 5.3 for inflow and from 2.16 to 3.5 for hydraulic head predictions). The analytical solutions underestimated the inflow compared to the numerical model for the time period of 2-19 weeks. The results presented in this paper can be used for developing an effective dewatering program.

Security of the multimedia data including image and video is one of the basic requirements for the telecommunications and computer networks. In this paper, we consider a simple and lightweight stream encryption algorithm for image encryption, and a series of tests are performed to confirm suitability of the described encryption algorithm. These tests include visual test, histogram analysis, information entropy, encryption quality, correlation analysis, differential analysis, and performance analysis. Based on this analysis, it can be concluded that the present algorithm in comparison to A5/1 and W7 stream ciphers has the same security level, is better in terms of the speed of performance, and is used for real-time applications.

The idea of active networks has been emerged in recent years to increase the processing power inside the network. The intermediate nodes such as routers will be able to host mobile agents and many management tasks can be handled using autonomous mobile agents inside the network. One of the important limitations, which should be considered in active networks, is the restricted processing power of active nodes. In this paper, we define an optimal location problem for monitoring mobile agents in a scalable active network as a p-median problem, which is indeed a kind of facility location problem. The agents are responsible to monitor and manage the performance of all of the network nodes such that the total monitoring traffic overhead is minimized. Then we proposed two methods of finding an appropriate sub set of intermediate nodes for hosting mobile agents. In our first method, we have not considered the limited processing power of active nodes, which host mobile agents. In our second method, we have solved the problem so that the processing loads of host nodes do not exceed a predefined threshold. Since p-median problems are NP-complete and the search space of these problems is very large, our methods are based on genetic algorithms. We have tested our two methods for finding mobile agents optimal locations on four network topologies with different number of nodes and compared the obtained location. By this comparison, we have shown the importance of considering processing load limitation for active nodes as a parameter in choosing them as hosts of mobile agents in a scalable active network. The proposed locations in our second method eliminates the probability of CPU overload in the active nodes hosting the mobile agents and reduces the processing time required for finding the optimal locations of mobile agents.

The advancement of technology has enabled new functions and possibilities for prosthetic devices. This advancement has introduced additional complexities for the user of the prosthetic devices. The added complexities can actually force the user to use simpler passive prosthesis rather than more complex and more flexible ones. This paper discussed the various aspects of the FUM Bionic Hand-I, designed and built at the Ferdowsi University of Mashhad. It also discusses the various efforts placed to simplify the usage of this prosthesis by its user. The FUM Bionic Hand-I has 5 degrees of freedom and consists of several sub systems such as pattern learning glove, wireless EMG Signal transmitter, RFID system for identify objects and a rich graphical user interface (GUI). These features works simultaneously in order to minimize the users' efforts on control a prosthetics hand and makes the hand intelligent enough to cooperate with user. Finally, the paper discusses the force control capability of the hand in order to allow object grasping.