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The paper provides a description of the electro-hydraulic steering gear and the principle of its action. The paper shows the development a mathematical model of the steering gear and the control system of the steering gear is given in the Simulink program of the MATLAB package. Based on mathematical model develop a real control system and show it block diagram with a description of its components. [ABSTRACT FROM AUTHOR]

This paper presents a method based on evolutionary algorithms for the planning of robotic trajectories both in 2D and 3D space. Space can be arbitrary shaped containing randomly sized and distributed obstacles. Different methods were implemented and evaluated for improving the speed and the level of the convergence of the algorithm. It is shown that evolutionary algorithm in its simplest form cannot effectively solve this problem in 3D. A thorough statistical analysis is performed for various instances of the algorithm, and the best algorithmic procedures are identified, documented, and explained in the paper. [ABSTRACT FROM AUTHOR]

This paper presents a new method of simulating the process of thin layer glass coating by magnetron sputtering on real industrial scale equipment and in real industrial application as well as necessary experimental results for the validation of the new developed mathematical formulation and software algorithm. Based on major differences between applications realized with laboratory equipment studied until now by other authors and the real scale industrial installations analyzed in present paper, development of a new mathematical model, simulation method and process control of magnetron sputtering systems by ionized physical vapor deposition (IPVD) was needed. Improvement of the deposition process by applying this new concept on industrial scale is discussed for different material types, specific deposition energy levels and the uniformity of the deposed layers based on simulation and experimental results analysis. [ABSTRACT FROM AUTHOR]

Today, more and more scientists agree with the hypothesis concerning the raising of the planetary ocean level due to global climate warming and consequently due to glaciers melting. Therefore, as a consequence of climate change phenomenon, the Black Sea level is raising as well, which led to the loss of significant areas of land due to marine erosion, but also the production of some cracks and penetration of salt water into the Razelm - Sinoe freshwater ecosystem in Romania. This paper uses a mathematical tool, which addresses the maintenance of the ecological balance of freshwater ecosystem, the transit of freshwater through the Razelm - Sinoe hydrotechnical complex, and from here into the Black Sea, required to ensure the hydraulic gradient from freshwater to saltwater. This would help maintaining vegetation as natural means for protection against the sea erosion, as well as to attenuate the coastal energy of waves, so as to ensure the shielding role together with the other coastal engineering construction. Besides, the strong reed vegetation represents a natural element of protection of levees already made or those in process of development, and also a retention element of fine particles brought by waves at times when sea level is high. The mathematical algorithm used in this paper take into account the principle of fluid flows in porous media. The vegetation of littoral from Razelm - Sinoe ecosystem was considered a porous media. The research results show the capacity of the vegetation to attenuate the waves' energy in the study area. The mathematical model was especially conceived for a unique littoral area, which separates the Black Sea from Razelm - Sinoe ecosystem. The solution of protection exploits the natural environment; it is not expensive and falls into the natural-ecological aspect of the coastal zone. [ABSTRACT FROM AUTHOR]

One of the major problems the city of Sarajevo is currently facing is the fact that in winter months the atmosphere is very polluted, mainly because of enormous usage of fossil fuels, primarily for heating. The other issue is the fact that it is extremely energy dependent, only a small portion of it’s energy needs is currently produced within the area of the city. These are the two main reasons for the analysis of the solar energy potential in Sarajevo. This paper focuses on analysing the available solar irradiance data obtained from several sources and on providing the exact mathematical method of the analysis, as well as on the results themselves. Furthermore, it also focuses on the effect of the surface tilt angle on the overall amount of the solar irradiance received by the tilted surface. After analysing and processing al the data, a more precise assessment of solar energy potential and the effect of the tilt angle on the overall irradiance received by the tilted surface in Sarajevo is given, as well as the guidelines for further research. [ABSTRACT FROM AUTHOR]

In decision-making models based on the Fuzzy Analytic Hierarchy Process, it is necessary to check the consistency of the fuzzy pairwise comparisons matrices. The consistency of the fuzzy matrix 3x3 can be checked on the basis of the similarity of the fuzzy numbers. In this paper, it is shown how to check the consistency of matrices of larger dimensions by decomposing these matrices to the 3x3 matrices. The consistency check of fuzzy matrices by decomposition is shown for pairwise comparisons matrices obtained by using fuzzified Saaty's scale. The direction for future research is proposed. [ABSTRACT FROM AUTHOR]

The adhesive joints belongs into most used connection in area of the composite components. The prediction of the strength of the bonded joints is still very problematic and many approaches can be used to dimension them. The paper deals with determining the strength of cylindrical composite adhesive joint using numerical simulation. In this case is used numerical simulation based on the finite element approach and cohesive elements were used as substitution of the adhesive. The experimental measurements were done for determination of necessary parameters of behaviour of gluing for cohesive zone model according ASTM standards. The parameters for mode I was determined by double cantilever beam test and the end notched three point bending test was carried out fo r finding parameters of mode II. Based on the obtained parameters, verification was performed on cylindrical s amples with the accuracy up to 6%. [ABSTRACT FROM AUTHOR]

In the first part of the research work it was offered to apply the desirable structures of system with the maximum degree of stability for automatic systems with unstable parameters. An example was given to show the effectiveness of the approach. Recommendations on the synthesis of the 4th order structures were given. In this paper the structures of 5 ÷ 8 orders are presented and a general method for the synthesis of the arbitrary order structures are given. It is shown that to build the desirable structure with real roots a non-stiff system of equations can be obtained and solved. Also, a method for selecting a structure based on the required parameters is proposed. [ABSTRACT FROM AUTHOR]

In many ways, engineering has always been dependent on mathematical background. This was usually mathematical analysis. In recent years, one of the areas of discrete mathematics - graph theory has been increasingly used in many fields, such as automation, programming or algorithms. In automatization process directed graphs are used for description and analysis of control system, where nodes represent states and arrows direct edges or transitions between states automaton that manages processes. In fact, as well as in other disciplines, automation for analysis and synthesis of control units are used in achievements of discrete mathematics. In this paper we show how to use graph to simplify the process of automation. We analyze the possibilities of using directed graphs for the purposes of analysis and synthesis of dynamic control system (elevator) with the aim of its simplification or minimization. [ABSTRACT FROM AUTHOR]

Huge amounts of visual data have been generated daily on the Internet. Created data requires not only massive storage but also massive computational power for processing and analyzing data in efficient manner. Therefore, new distributed platforms like Hadoop are becoming more popular because of their capability to deal with huge amount of complex data in real time. MapReduce, a part of Hadoop, is frequently used programming model for writing distributed applications. This paper describes and presents results of MapReduce-based face detection process using Hadoop platform on BIOID image database. [ABSTRACT FROM AUTHOR]

The issue of cost calculation of processes pursued in enterprise in the context of effective management of these processes has been carried out in the paper. The essence of process management and difficulties linked with measurement and improvement of processes in organizations have been described. Next the discussion concerns the imperfection of traditional methods of cost calculation. The cost calculation method based on Activity Based Costing has been proposed to enable precise processes cost determination together with its structure and continuous improvement of these processes. Finally, benefits and difficulties related to the implementation of the proposed method have been pointed out. [ABSTRACT FROM AUTHOR]

The choosing of a structural variant, is one of the main problems solved during the design process of complex technical systems. The real world conditions demand this choice to be made, on the basis of a set of criteria, which in the general case are conflicting. In the present paper are given the results, from the development of an interactive software system for multicriteria optimization, aiding the designers of technical products, during the decision making process of choosing of a structural variant. While developing the software system, the specifics of the problem have been taken into account. An effort has been made, for avoiding the disadvantages of similar, already known software systems. The application of the development is illustrated with a solved example. [ABSTRACT FROM AUTHOR]

The dynamic model of a planetary chain increaser used in small hydro is presented in this paper. The dynamical aspects presented in (Saulescu et al, 2009) represent the basics for the dynamic model presented in this paper. The dynamic response is obtained by means of Matlab-Simulink software. [ABSTRACT FROM AUTHOR]

The dynamic model of a planetary chain increaser used in small-hydros is presented in this paper. The paper approaches the appropriate structural, kinematical and dynamical aspects; the presented relations are going to be used during the dynamic modelling of the increaser. [ABSTRACT FROM AUTHOR]

The paper present a method for optimal design of non-standard spur gears, with the aim of minimising multi-objectives optimisation functions, obtained by weighted sum of different evaluation function, represented of the significant values of some functional parameters. Those parameters can be carrying out with designing and analysing computer applications. The paper is focused on using original MATLAB application, based on genetic algorithms, developed for optimal design, with the aim of simultaneous minimising the contact stress and bending stress on the pinion and on the gear, of asymmetric gears. Having asymmetrical involutes teeth profiles, asymmetric gears are non-standard gears obtained with the "direct gear design method", used for improving the performances of the involutes toothed gears. [ABSTRACT FROM AUTHOR]

The main objective of this paper is the numerical investigation of fracture behaviour in polymeric particulate composite with rigid particles. This article is focused on estimation of next micro-crack propagation in nonlinear matrix. The composite is modelled as a three-phase continuum and using finite element method is solved. The interaction of micro-crack and particles covered by the interphase is analyzed. [ABSTRACT FROM AUTHOR]

In the paper behaviou of a function present graphs of a functions by using mathematical analysis and graphical methods that include plotting points and determined symmetry. These techniques are adequate for obtaining a graph. We can use properties of the functions to predict some parameters of he technological experiments for example the height and speed of the manufacturing. The presentation functions are inspirative and motivated for the manufacturing experiments. We study important geometric properties of the curves. [ABSTRACT FROM AUTHOR]

This paper highlights analysis and optimization method of junction layered composites structures using finite elements analysis (FEA). In practice, there are many junction structures made from alloy or composite materials. The authors was effectuated a study for one type of structures made from layered composites material namely a junction between a tube and a flange. The optimization process was accomplished in two steps: the first step was the static analysis of the structure and the second step was the optimization process aiming at the weight reduction of the entire structures. [ABSTRACT FROM AUTHOR]

The paper present the effects of change of lean manufacturing implementation in a company focusing on following objective: to synthesis all involved procedures, stages and instruments, to draw up a FMEA table for a real case study (a windmill farm), to measure the efficacy, efficiency for cell versus line manufacturing. [ABSTRACT FROM AUTHOR]

The paper presents an original stern shape design. It leads to a better fluid flow, which reduces the drag. There are presented the direct and reverse problems and the numerical implementation. A current tube is taken into consideration. It contains the propeller, extends towards the prow and includes the entire stern section of a classic hull. The dynamics of a propeller depends on environment system. The fluid flow around a propeller working on a ship is different to that one tested in free water or in a cavitation tunnel. The fluid flow near the stern is a key factor for the ship design. The consequence is that a new stern design is a solution of drag reduction of ships. [ABSTRACT FROM AUTHOR]

Designing a manufacturing system requires modelling and performance evaluation techniques. To support this, a modelling method based on timed Petri nets is presented in this paper. A graphic construction of the net is achieved; transporting it into a specific mathematical formalism it is made, so that the fulfilled structure to be fully retrieved and used to bring out the internal dynamics of the model. The timed Petri net model is implemented in Petri Net Toolbox under MATLAB environment. There are determined the global performance indicators in order to evaluate the performance of the considered flexible manufacturing system. [ABSTRACT FROM AUTHOR]

The complexity of an algorithm is usually expressed using complexity functions and complexity classes, in this paper we present a method to reduce the work with multi-variable complexity functions to the work with one-variable complexity functions. We define five complexity classes for multi-variable complexity functions and then we prove some properties for these classes. [ABSTRACT FROM AUTHOR]

This paper presents a method to calculate the stress intensity factor using in the J-integral method. After the explanation of theoretical aspects, an application using two different F.E.A. programs is solved to illustrate feasibility of the method. The results obtained using F.E.A. are similar to those obtained with the analytical method. [ABSTRACT FROM AUTHOR]

The paper presents a numerical determination of the strain state in a structure using the finite element method. The omputation results were compared with the ones obtained using experimental measurements with electric transducers. The aim of this work was to determine the strain state in the bed of a press for curing the component elements of a rubber belt with a metallic insertion. [ABSTRACT FROM AUTHOR]

This paper presents an original greedy constructive algorithm for solving the permutation flowshop scheduling problem with makespan optimization criterion. The algorithm starts with a pair ofjobs chosen based on optimization criterion and adds every new job to the schedule by means of a greedy selection procedure. Expansive computational experiments indicate that, concerning the quality of solutions, selective greedy heuristic performs almost as well as NEH algorithm. [ABSTRACT FROM AUTHOR]

This paper solve a problem of optimal control with fixed limits using The Pontreaguine Maximum Principle. (Pontreaguine, 1974) This problem is modelling in mathematical way the new products launch. The order of these two control functions application conduce to two minimum strokes. Therefore we have the possibility to choose the smallest one. [ABSTRACT FROM AUTHOR]

The present technology used for the generation of an electromagnetic pulse (EMP) in defence applications has been implemented starting with three sorts of generators so far: flux compression generators (FCG), magneto-hydrodynamic (MHD) generators and virtual cathode oscillators (VCO). This paper describes the basic principles of the most common and effective type of generator, the FCG and particular results obtained by a research team of the Romanian naval academy during designing and building an electromagnetic bomb prototype. As the FCG requires a coil, the authors present hereinafter the preliminary calculations of the output current that have been used in the actual design. All the results presented hereby have been demonstrated by the actual prototype developed. [ABSTRACT FROM AUTHOR]

The paper describes the implementation of a two method in which an initial CAD model is updated from a physical model. To obtain a geometric model from an existing physical model relatively complex and for which there is no technical documentation we will present two methods - reverse engineering and 3D sketch. [ABSTRACT FROM AUTHOR]

This paper presents specific aspects of the beam structures junctions nonlinear calculus. The substructuring method applied with the help of some high-performance numerical methods is considered the only way to study some high level stress zones. The working methodology has an original character and may be generalized to all structures with geometrical and material discontinuities. The stress state configurations obtained using the finite element method allow a correct evaluation of the safety coefficients and reliability of the analyzed structure. [ABSTRACT FROM AUTHOR]

CFRP laminated composite plates subjected to low velocity impact have been investigated in this paper using an instrumented drop-weight test device. For response parameters evaluation of the low velocity impact test a simple block diagram using LabVJEW program is presented. The investigations was done on composite laminates plates carbon/epoxy vinyl ester made of symmetrical laminate with 8 unidirectional laminae and [01-451+45/90], stacking sequence, simply supported at the edges. [ABSTRACT FROM AUTHOR]

This paper presents results obtained from computational simulation models for cutting process. The objective of the present study is to evaluate tool wear using simulation of mechanical cutting. The orthogonal cutting process has been simulated by the finite element code, explicit code DEFORM 3D. This software is a commercial code which contains a module developed especially for simulating mechanical metal cutting. [ABSTRACT FROM AUTHOR]

Multi-disciplinary design optimization methods of sandwich structures have not been clearly established yet. in this paper, it is presented a method that uses a fuzzy control loop system to fit the individual components properties of a sandwich assembly to its overall properties or functional capabilities. The method may be useful in the primary stage of a sandwich panel design in order to reduce time and cost, providing useful information for further analysis. [ABSTRACT FROM AUTHOR]

The paper presents a method of designing a solid model of the deformed flexspline of a harmonic drive. The deforming curve was considered an ellipse. The purpose is to create a deformed flexspline with real positions of the teeth around the circumference of the flexspline. The technology for the model definition uses the program AutoCAD 2009, and involves two special functions: lofting and divide. [ABSTRACT FROM AUTHOR]

The paper is analysing the dynamic stresses induced by the mechanical vibrations of an electronic circuit plate, considering the most usual situations dealt with in engineering practice. The corresponding calculi models are deduced and for one of these models the results of the experimental study carried out are presented and discussed. [ABSTRACT FROM AUTHOR]