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The issue of limiting power correlation of electromechanical systems of edging and horizontal rolls of universal mill stand is relevant and understudied. The paper determines causes of looping or tension in the strip in the steady-state rolling mode. Main causes are incoordination of linear speeds of edging and horizontal rolls and steady-state error of speed control of DC electric drive at on-load operation. The method of coordination of horizontal components of linear roll speeds at universal stand has been developed. It is based on condition of equality of metal second volumes at outputs of edging and horizontal rolls. The paper considers the method of control of electric drives at the universal stand that provides compensation of static speed deviation of horizontal rolls due to control of edging roll speeds during simultaneous rolling. It proposes the structural diagram and analyses the functional concept of the device implementing this method. There are oscyllographs of coordinates of electric drives of edging and horizontal rolls obtained during experimental investigations of this method. It is shown that speeds of edging rolls may be corrected practically without error. The authors substantiate that speed control of the edging roll electric drive according to the difference of horizontal roll speeds before and after strip gripping eliminates inter-stand forces. They give recommendations for commercialization of the algorithm realizing the developed methods of speed coordination of electric drives at the universal stand. [ABSTRACT FROM AUTHOR]

The paper describes the software module development for the processing of the experimental data obtained during the tests of running machines with the metal-concrete basic components. To develop the software module, an integrated block algorithm based on the method of computing the machine bed oscillation decrement is proposed. The module allows computing the damping decrement and filing a report according to user-preferred testing result files. The test data for thirteen machines has been processed in the developed module. As a result, a set of report files forming a summary table has been derived. The table data are analyzed and interpreted at the end of the paper. [ABSTRACT FROM AUTHOR]

Checking mesh validity is a mandatory step before doing any finite element analysis. If checking the validity of tetrahedra is trivial, checking the validity of hexahedral elements is far from being obvious. In this paper, a method that robustly and efficiently compute the validity of standard linear hexahedral elements is presented. This method is a significant improvement of a previous work on the validity of curvilinear elements [1]. The new implementation is simple and computationally efficient. The key of the algorithm is still to compute Bézier coefficients of the Jacobian determinant. We show that only 20 Jacobian determinants are necessary to compute the 27 Bézier coefficients. Those 20 Jacobians can be efficiently computed by calculating the volume of 20 tetrahedra. The new implementation is able to check the validity of about 6 million hexahedra per second on one core of a personal computer. Through the paper, all the necessary information is provided that allow to easily reproduce the results, i.e. write a simple code that takes the coordinates of 8 points as input and outputs the validity of the hexahedron. [ABSTRACT FROM AUTHOR]

The paper presents some conclusions on the differences between the manufacturers’ indications and the in situ practical observations of the optical fibers communications networks. Following the experimental results on preinstalled optical fiber telecommunication underground networks, blown by specific equipment, it is proposed a mathematical model for the whole system “network-equipment”, which can explain the physical phenomena. The experiments were developed made for real tubes, penetrated by optical tubes, both in laboratory and on real networks, and the results were similar. The differences from these real tubes and the tubes proposed for the ideal case is that these tubes are penetrated by several microtubes and that they are placed in positions similar to the real ones founded in practice. The providers technical specifications do not presents the differences between the laboratory and practical conditions and their effects on the blowing length of the optical fiber within the network. The proposed model considers the equipment providers indications as some theoretical ones, characterized by absolutely linear motion and parallel position of the optical fibers. This ideal situation is verified by the model. In practice, any exception from these hypotheses produces a shortening of the length of penetration. The paper emphases the reasons of differences between the optical fiber penetration lengths observed in practical situation of communication networks and the penetration length indicated by the equipment providers. [ABSTRACT FROM AUTHOR]

This paper presents the mathematical modeling of a multivariable process used in level control, under the assumptions that all pipes are filled with fluid and the inertial effects caused by flow variations, in case of small accelerations, are neglected. Because of the way the two tanks are interconnected and interact with each other, the resulting mathematical model is nonlinear. In the paper it is proposed a robust control algorithm for this plant developed based on H-infinity loop shaping procedure. The required computations and the study of the behavior of the system are done in the Matlab simulation environment. [ABSTRACT FROM AUTHOR]

The sequences play an important role on many application areas. The strings as symbol sequences are investigated mainly in natural language processing and biological modeling. This paper investigates the transformation process of the strings and it proposes a method for induction of the string transformation rules. The presented method is based on the application of an FCA lattice for generalization of the transformation rules. The paper introduces an efficient construction algorithm for building the conceptualization lattice. Based on the performed comparison tests, the proposed method outperforms the main incremental methods and for some parameter ranges, its efficiency is comparable with the efficiency of the best batch methods. [ABSTRACT FROM AUTHOR]

Malfunctions of contemporary IT systems caused by security violations are so common and frequent that in dependability analysis now they are treated in the same way as the traditional reliability theory considered “classic” failures. For this reason to improve overall system reliability today it is necessary to apply appropriate cryptographic methods. In this paper we are dealing with one class of such methods which are based on so called hash functions, considering one specific method – the BLAKE algorithm. BLAKE was developed as a candidate for the SHA-3 contest where it successfully qualified to the final round and although it eventually lost to KECCAK it is still considered as a suitable solution with good cryptographic strength and sound performance especially in software realizations. In this paper we discuss specific modification of its hardware implementations which use built-in block RAM modules available in contemporary Field Programmable Gate Arrays. The purpose of the modification is to eliminate involved distribution of message bits among the cipher rounds in order to reduce occupation of in-array resources and also to improve performance metrics. The idea is tested on 4 different architectures: the standard iterative one and three high-speed loop-unrolled organizations with 2, 4 and 5 rounds instantiated in hardware. The results found after their implementation in a popular Spartan-3 device form Xilinx are compared to parameters of analogous architectures implemented without memory so that the savings in array utilization can be compared against additional cost incurred by the RAM modules. [ABSTRACT FROM AUTHOR]

The paper describes various modified algorithms of classical sinusoidal pulse width modulation (PWM) serving for a three-phase two-level inverter control. The paper presents the results of a research of 3 PWM versions with varying duty cycle parameters and frequency of the pulse signal modulation. The method is to divide the modulated sinusoidal signal cycle (half-cycle) into intervals in order to change the modulation frequency within the separate sectors of forming the quasi-sinusoidal output voltage waves. In addition, algorithmic ways to compensate the additional losses in the inverter and the induction motor at high modulation frequencies of a discrete control signal are investigated and described in the paper. Calculations and simulations are performed by NI Multisim simulation program and NI LabVIEW visual programming environment. Theoretical studies are performed using the electric drive theories, discrete control systems and spectral analysis. The practical implementation performed by Texas Instruments Stellaris Launchpad using the Energia prototyping platform, field-programmable gate arrays (FPGA) of National Instruments CompactRIO-9074 and NI Single-Board RIO GPIC (sbRIO-9606, NI 9683 (GPIC), LX45 FPGA) using NI LabVIEW software and add-on modules (LabVIEW Real Time, LabVIEW FPGA). The suggested inverter control methods make it possible to reduce the distortion of the output quasi-sinusoidal signal and reduce the power consumption of the DC link while significantly reducing the number of inverter transistor switching in comparison with the classical method without premodulation or technical devices (filter-compensating devices). [ABSTRACT FROM AUTHOR]

Two major generalizations of the Precedence Diagramming Method (PDM) and an algorithm solving the generalized network are discussed in this paper: a) Two new types of precedence relations are introduced: minimal point-to-point and minimal continuous relations; b) Non-linear production-time functions can be defined in order to better adapting the model for real life situations. The activity progress-in-time function can be any strictly increasing continuously derivable function. The mathematical model, and the algorithm is shortly described, then the calculations are shown in details through an artificial example project. The emphasis is on the calculations, as this example project will be used in other papers on generalized PDM models. [ABSTRACT FROM AUTHOR]

In simulated annealing the probability of transition to a state with worse value of objective function is guided by a cooling schedule. The more iterations are spent, the more strict the acceptance probability function becomes. In the end of the optimization process, the probability of transfer to worse state approaches zero. In this paper the principles of cooling schedules are used to control the parameters of local search methods in the memetic algorithm. The memetic algorithm in this paper is a combination of genetic algorithm, Hooke-Jeeves method, Nelder-Mead simplex method and Dai-Yuan version of nonlinear conjugate gradient method. The controlled parameter of Hooke-Jeeves method is the radius r, for Nelder Mead method the size of edge of the simplex and the length of step for nonlinear conjugate gradient method. [ABSTRACT FROM AUTHOR]

In this paper, the problem of accuracy control of machined complex profiles is investigated. Presented are schemes of the mechanical load of the cutting tool as a function of the current angle of the machined profile. A simple method for compensating the profile error caused by mechanical deformations is suggested. Presented is an algorithm for the automatic measurement of the machined profile and for the compensation of the profile error. [ABSTRACT FROM AUTHOR]

This paper proposed a TRIZ-based systematic Device Trimming Algorithm with theory and application. The method can be used to resolve process-machine problems by re-designing the problematic processing machines or simply used to trim components for various purposes. The trimming process is orchestrated by a trimming plan which consists of sequenced trimming tasks. Elements of each trimming task include function carrier, useful functions, objects, trimming rules, new carriers, trimming problem statement, and trimming method. A 2-loop depth-first recursive trimming process is proposed to maximize the trimming effect. Applied on a slit-valve failure of a chemical vapor deposition equipment in one of major Taiwanese foundry companies, the proposed problem solving process successfully identified the critical key disadvantages of the problem and solved the slit-valve failure with breakthrough results. A number of solutions were generated by the integrated process which involves a number of TRIZ tools. This paper describes only the solution by the trimming process. The main contributions of this paper include:1) Establishing an integrated trimming process consistent with TRIZ problem-solving model and capable of breakthrough problem solving and cost savings; 2) Solving the slit-valve problem with 83.3% component count reduction, 95% component cost reduction, 99% operational energy reduction, and completely designed-out the original failure mode. The results have been converted into a patent pending approval. [ABSTRACT FROM AUTHOR]

The paper describes an algorithm for the synthesis of neural networks to control gyrostabilizer. The neural network performs the role of a state vector observer. The role of such an observer is to provide feedback on gyrostabilizer, which is illustrated in the article. The paper details the issue of specific stage-related peculiarities of classic algorithms: choosing the network architecture, learning the neural network and verifying the results of feedback control. The article presents an optimal configuration of the neural network like memory depth, number of layers and neurons in these layers, and activation layer functions. It also provides data on dynamic systems to improve learning neural network learning. There is also provided an optimal training pattern. [ABSTRACT FROM AUTHOR]

Recently developed point-to-point relations have greatly extended the modeling capability of the Precedence Diagram Method. These relations can connect any inner (and extreme) points of the related activities. Furthermore, the definition of multiple relations is allowed between the same two activities. These features make point-to-point relations suitable for modeling overlapping activities more easily and with greater precision than it was possible before. However, there is a lot of work ahead. Although both proper mathematical modeling, and the algorithm that handles both minimal and maximal relations are available, re-investigation of well-known definitions for float, critical path, critical path metrics, classification of critical activities etc. are still missing. This paper deals with the investigation of the critical path. It describes the ways in which an activity can be part of the critical path. Collecting the possible cases provides the opportunity for classifying critical activities. The main result of the paper is that it provides a method for determining the type of the critical activity based on the relationships going in and out of the activity. [ABSTRACT FROM AUTHOR]

Energy consumption monitoring and regulation on large-scale public buildings are always an indispensable part in building energy conservation. With the mounting establishment of the building sub-metering platform, massive amounts of historical power consumption data are provided. In this paper, different building types of six large-scale public buildings in Shanghai are selected, with their sub-metering data deeply analyzed. The concept of CDHs/HDHs (cooling/heating degree hours) is introduced and weekly prediction models of total building power consumption are proposed by the way of multiple linear regression algorithm which is relatively simple and easy to understand. The prediction models are validated to have great accuracy and general applicability in the paper, offering reliable instructions to the building facility manager and relevant competent authorities in terms of decision making and policy implementation. [ABSTRACT FROM AUTHOR]

Mesoscale modelling of porous materials may require building explicit geometric models for porous microstructure. Such microstructure models are composed of connected voids (pores) embedded in an otherwise impermeable solid. Having such a model at hand it is possible to directly calculate several characteristics of the pore microstructure, for instance pore radii, pore lengths, pore wall surface area as well as spatial distribution statistics. Additionally, having a solver capable of simulating fluid flow through such model, it is possible to gain insight into the effects of pore microstructure characteristics on flow properties, both macroscopic, such as permeability, or microscopic, such as tortuosity. In their recent paper Hyman and Winter [1] discuss an algorithm for stochastic generation of explicit pore structures by thresholding Gaussian random fields. Unfortunately their paper is missing an discussion on effective implementation of the presented algorithm. In our paper we fill this void by providing detailed discussion on implementation side of the algorithm discussed by Hyman and Winter. Besides presenting a microstructure generator which we provide as Open Source program, this paper shows how generated model can exported to data formats suitable for analysis and visualisation with various tools, for instance data formats based on VTK library. The programs described in this paper can form a base for handy tools and reduce the programming effort of building simulation environment for materials microstructure analysis. [ABSTRACT FROM AUTHOR]

This paper is based on specific applications of Material Flow Theory (MFT) in industrial engineering material flow management (MFM). The accent is put on exploring different possibilities to increase productivity and profit in processing architectures using the MFM approach based on virtual modelling and simulation. In this context the paper presents a case study using virtual modelling of a flexible processing architecture and MFM simulation algorithms for diagnosis and optimization. The virtual model of the processing architecture will be used as a tool for identifying and eliminating the flow concentrators and obtaining an improved productivity of the system. [ABSTRACT FROM AUTHOR]

This paper studies on key techniques of aeronautical ad hoc network MAC and network layer based on the analysis of aeronautical ad hoc network application requirements as well as its own characteristics. MAC core processing architecture and binary exponential back-off algorithm based on QoS are designed based on the analysis of the SPMA state flow.Network layer core architecture is designed in view of the network layer functional requirements, and several key technique pointssuch as network synchronization, network admittance and routing maintenance are designed and analyzed. The simulation results show the effectiveness of the design in this paper, and the design has a positive significance for designing of new concept aviation wireless communication products based on network centric warfare. [ABSTRACT FROM AUTHOR]

A structural health monitoring system consists of permanently installed sensors to collect structural information, and these sensors are required to be placed at ‘good’ positions for damage identification. Conventional sensor placement methods make use of dynamic characteristics of a structure, i.e., mode shapes and natural frequencies, to determine optimal sensor positions. The engineering community has traditionally relied on these modal methods and finite element analysis for dynamic predictions in the low frequency range. However, these techniques become ineffective in mid frequency range due to large number of modes and high modal density. In view of this, in this paper, an optimal sensor placement technique which can be employed for low as well as mid frequency range structures for structural health monitoring as well as structural system identification is presented. The frequency domain based optimal sensor placement technique (FEfi) presented in this paper makes use of principal components evaluated from frequency response functions at the desired frequency levels. Numerical examples with optimally placed sensors dictated by the proposed algorithm are presented and compared with the popular effective independence (Efi) technique based on mode shapes. [ABSTRACT FROM AUTHOR]

Existing and widely used scheduling techniques suffer from many shortcomings and drawbacks. These are mainly due to the oversimplifications made in the late 50s, early 60s to adjust these scheduling models to the available mathematical and IT tools. In this paper, these shortcomings of network techniques are collected and classified. Following this, a new general model can be defined using a new representation system that allows, for example: • the use of loops for determining recurring activities, • precedence relations with arrows at both ends for modeling the sequencing problem in construction, • precedence relations that can be used to describe minimal and maximal spatial distances, • decision nodes with or without probability, etc. The third point of the above list is discussed in detail; an algorithm is presented in order to define the start of the succeeding activities, when the intensity of the activities change and both spatial and time distances can be defined. The algorithm is presented with the help of a practical example; generalization can easily be done based on this. Resources are assumed to be unlimited throughout the paper unless explicitly stated otherwise. The main result of this research is a more general scheduling model that better fits the needs of project planners than the existing methods. [ABSTRACT FROM AUTHOR]

Abstract: The present paper concentrates on the actual use - in the framework of a Tsunami Early Warning System - of the algorithms to be implemented in the software of wind-wave gages in order to automatically perform the real-time detection of tsunamis within recorded signals. Focus is on the amplitude-discriminating algorithm, mainly based on an infinite impulse response time domain filter, proposed by the authors in a previous paper. In particular, the problems that may arise in filtering out ‘disturbances’ such as long tidal waves are addressed, and an original method to perform the full characterization of the waveform of an actually detected tsunami, automatically and in ‘quasi’ real-time is proposed. Tests were carried out using time-series resulting from the superposi- tion of actual tsunami signals recorded by some of the tsunamometers of the Deep-ocean Assessment and Reporting of Tsunamis program, and different wind-wave signals synthesized by means of the random-phase method. In particular, the tsunamometers’ records collected during the events triggered by the earthquakes occurred off the coast of Chile on February 27, 2010, and off the Pacific Coast of Tohoku (Japan) on March 11, 2011, were used. The results show that the overall detection and characterization of a tsunami can be effectively carried out, automatically and in real-time, using the proposed new algorithm. [Copyright &y& Elsevier]

Abstract: Industries have lots of benefit by integrating sensors in industrial plants for continuous sensing and monitoring the status of the system. This paper discusses the efficient process monitoring of pipelines that carry oil, gas, water, and other important resources for an essential infrastructures. A Wireless Sensor Networks (WSN) should be designed to obtain maximum throughput of data to efficiently monitor the health condition of the system and obtain timeliness for handling critical events in case of emergency. A real-time Multichannel Process Control Monitoring System is designed to monitor and control large network. For any real time system timeliness and throughput are equally important but are obtained on the compromise of each other. This paper proposes a Multichannel Process Monitoring Algorithm (MPMA) which brings a balance between timeliness and throughput by increasing in number of operating channels. The protocol has been implemented and experimentally evaluated on a testbed using nodes with standard IEEE 802.15.4. It has been observed that the proposed algorithm has shown an increase in timeliness and throughput compared with the standard algorithm. [Copyright &y& Elsevier]

Abstract: This paper presents an overview on optimal overcurrent relay coordination in protection system and protective relays. Efforts have been made to include all methods used for the coordination of overcurrent relays. It includes techniques, such as Artificial Intelligence (AI) and Nature Inspire Algorithm (NIA) as well as other conventional methods used for overcurrent protection. A brief mentioned is made about conventional methods while more prominence is given on the application of AI and NIA for the protection of overcurrent relays. This paper presents a set of references of all respective papers related and provides a brief summary of the research work. In addition, the results of these techniques also provided in the respective references. [Copyright &y& Elsevier]

Abstract: In most of the medium scale industries, demand is uncertain and difficult to forecast. Hence Ordering in right quantities at right time is always a crucial issue. In this paper; the authors present a model for determining the ordering policy which will minimize the total inventory cost. This paper takes into consideration various models such as lot by lot size, economic order quantity, periodic order quantity, least unit cost, least total cost, least period cost, Wagner-Whitin algorithm etc. Total annual inventory costs for various items are calculated by each method. The results obtained by applying each model for different items are summarized which shows that Wagner-Whitin algorithm gives optimum cost in each case. [Copyright &y& Elsevier]

This paper presents a newly developed mesoscopic model with grid-based structure for building evacuation simulation. The evacuation space in this model is discretized into cells with larger size than that of the microscopic models. This mesoscopic model directly computes the density flow between the cells governed by the density flow algorithm. The computation speed is higher than the traditional cellular automata model in which the movements of all pedestrians should be tracked for calculating the crowd density. To test the feasibility of this model, we applied it to a typical scenario in which pedestrians evacuate from a square room with single exit and conducted parameter sensitivity study on the length of the time step δ. The simulation results show that, within a valid range, changing δ only has minor influence on the evacuation process. We can directly identify area with high density as bottleneck from dynamically changed density map even the relatively large time step is adopted. In addition, the commercial package AnyLogic was used to benchmark the performance of this model. The results show that the mesoscopic model discerns evacuation patterns in more details compared to the macroscopic models and with higher efficiently computational speed than the microscopic models. [ABSTRACT FROM AUTHOR]

The paper investigates the production planning process. Due to the large dimensions and complex constraints of the production sequencee of parts and assembly units, the process-planning problem belongs to the NP-complex class. The aim of the work was to develop an algorithm that allows forming a feasible schedule, which is close to the optimum, minimizing the length of the production cycle. The authors propose an algorithm for determining the order of the item and assembly processing units of the product to entitle it "Falling Leaves". The algorithm is based on a stratified cutting the end vertices (leaves) of the tree structure of electronic products and ranking the group leaves depending on the duration of the production path. This approach allows us to start the production of products with the parts having the longest production cycle. Computational experiments on the products of varying complexity and the comparison with the existing algorithm have been conducted to determine the order of processing of parts and assembly units at the level of entry into the structure of the product. The results show that the developed algorithm "Falling Leaves" decreases the production cycle of products by 2% to 30%. [ABSTRACT FROM AUTHOR]

Indirect hex-dominant meshing methods rely on the detection of adjacent tetrahedra that may be combined to form hexahedra. In this paper we introduce an algorithm that performs this identification and builds the set H of all possible combinations of tetrahedral elements of an input mesh T into hexahedra. All identified hexahedral elements are valid for engineering analysis. The new method first computes all combinations of eight vertices whose connectivity in T matches the connectivity of a hexahedron. The subset of tetrahedra of T triangulating each potential hexahedron is then determined. Quality checks allow to early discard poor quality hexahedra and to dramatically improve the efficiency of the method. Each potential hexahedron is computed only once. Around 3 millions potential hexahedra are computed in 10 seconds on a laptop. We finally demonstrate that the set of potential hexes H built by our algorithm is significantly larger than those built using predefined patterns of subdivision of a hexahedron in tetrahedral elements. [ABSTRACT FROM AUTHOR]

This paper describes the implementation of an efficient and robust advancing layer viscous mesh generation method for complex 3D configurations. The method employs a pre-processing algorithm to identify cells that can be generated without further checkings, whereas the rest of the cells are checked by a standard layer-by-layer procedure. This method significantly reduces the number of proximity/intersection checking operations, substantially decreasing the mesh generation wall-clock time while maintaining the same robustness and quality of the baseline method. The practicability of the algorithm is demonstrated using examples of industrial complexity. Mesh generation time is reduced typically by a factor which oscillates between four and ten, with respect to the conventional advancing layer method. This factor grows with the number of layers and depends on the complexity and topology of the domain. This approach has proved to be useful for large size 3D complex configurations where mesh generation time and interactivity are crucial. [ABSTRACT FROM AUTHOR]

The sweeping algorithm is a classical algorithm that can generate high quality hexahedral meshes for swept volumes. However, the traditional sweeping algorithm can only generate single axis swept meshes. In order to expand the scope of the model that sweeping algorithms are applicable to, this paper proposes a global multi-axis swept mesh generation approach, which can robustly generate hexahedral meshes for solid models composed by multi-axis swept volumes. We first globally generate all the surface meshes by applying an optimized structured quadrilateral mesh generation algorithm. After that we generate a swept mesh for each swept volume. Finally, we determine an appropriate way to optimize the topology of the generated mesh so as to improve the mesh quality. The experimental results show the effectiveness and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

The eye’s fundus is a complex object with a high density of filling vessels. The procedure of fundus treatment requires a lot of experience and skill from the physician. The basic tool in fundus treatment is laser coagulation, when a series of metered microscopic thermal wounds – laser coagulates – are applied in edema on the eye’s retina. Currently available software packages are focused first on the use of the specified template (pattern) for coagulate location. Effects of the pattern application are caused by irregular coagulate location by reason of high variability in edema and vasculature forms. The paper presents algorithms for calculating a coagulate map within the framework of the solution of the sphere close-packing problem in a random region and research results for developed algorithms. For automatic coagulate arrangement, we proposed a software package including the proposed algorithms. [ABSTRACT FROM AUTHOR]

In this paper, we present models, methods and algorithms designed and developed with the aim of increasing the efficiency of information technology for producing digital graphic documents. The hierarchical model of structured description of raster images of graphic documents, 3D контроль ошибо1the two-criteria recognition algorithm with self-learning, algorithms for automatic assembling of composite linear and discrete objects, methods for increasing the automated component of interactive editing procedures and assigning classification types to automatically generated templates, 3D modeling and visualization methods at the stages of interactive control and editing that have been implemented in the framework of the proposed technology contribute to a significant increase in time efficiency. The results obtained are demonstrated using the example of digitizing some typical images of real-world documents. [ABSTRACT FROM AUTHOR]

A new attack aimed at DM-QIM watermark was proposed in (Mitekin, 2016). Key recovery results obtained during proposed attack show that for a set of watermarked images it is possible to detect DM-QIM watermark in case if non-local image statistics is utilized. In the present paper, a new modified QIM-based algorithm is proposed for images and video watermarking which shows better robustness against known histogram-based attack. The proposed algorithm is based on modified “correlation-immune” scalar quantizer and does not introduce any correlation between the key bit and the intensity of an individual pixel of the host image. Also, the robustness of proposed algorithm against AWGN is investigated. [ABSTRACT FROM AUTHOR]

With the goal of reducing the investment in monitoring equipment and simultaneously keep an adequate accuracy in structural condition assessment, this paper studies the results that can be obtained with different strategies of instrumentation of a 2.0 MW onshore wind turbine. The data processing strategy is based on the continuous tracking of the wind turbine main vibration modes using Operational Modal Analysis techniques combined with algorithms that deal with the particularities of operation of the wind turbines and that permit an online automated identification. A database of continuously collected acceleration time series during one year is used to evaluate the efficiency on the monitoring system on the detection of simulated damage scenarios, considering variations on the number of sensors, on their distribution in the wind turbine tower and on their noise level. [ABSTRACT FROM AUTHOR]

Approximate Bayesian Computation (ABC) methods are originally conceived to expand the horizon of Bayesian inference methods to the range of models for which only forward simulation is available. However, there are well-known limitations of the ABC approach to the Bayesian model selection problem, mainly due to lack of a sufficient summary statistics that work across models. In this paper, we show that formulating the standard ABC posterior distribution as the exact posterior PDF for a hierarchical state-space model class allows us to independently estimate the evidence for each alternative candidate model. We also show that the model evidence is a simple by-product of the ABC-SubSim algorithm. The validity of the proposed approach to ABC model selection is illustrated using simulated data from a three-story shear building with Masing hysteresis. [ABSTRACT FROM AUTHOR]

The paper deals with the estimation problems for uncertain nonlinear dynamical systems in the case when a probabilistic description of noise and errors is not available, but only bounds on them known. Such models are found in many applied areas ranged from engineering problems from physics to economics as well as to biological and ecological modeling when it occurs that a stochastic nature of the errors is questionable because of limited data or because of complexity and nonlinearity of the model. As alternative to a stochastic characterization, a so-called set-membership approach has been proposed and intensively developed in the last decades. The solution of many control and estimation problems under uncertainty involves constructing reachable sets and their analogs. For models with linear dynamics under such set-membership uncertainty, there are several constructive approaches, which allow finding effective estimates of reachable sets. Certainly, concrete problems are mostly nonlinear in their parameters and the set of feasible system states is usually non-convex or even non-connected. The key issue in nonlinear set-membership estimation is to find suitable techniques, which produce related bounds for the set of unknown system states without being too computationally demanding. Here the problem of estimating reachable sets of nonlinear dynamical control systems with combined bilinear and quadratic nonlinearity and with uncertainty in initial states is studied. Applying results of the theory of trajectory tubes of control systems and related techniques of differential inclusions theory we present approaches that allow finding the upper ellipsoidal estimates of reachable sets. The main new result consists in obtaining ellipsoidal estimates for reachable sets of nonlinear dynamical system with additional state constraint of ellipsoidal type. Related numerical algorithms, examples and results of computer simulations are included. [ABSTRACT FROM AUTHOR]

This paper presents a modified form of clipped-optimal control for seismic mixed base isolation, combining passive isolators and semi-active viscous dampers. The objective is to limit base displacement while avoiding undesirable amplification of the response of the non-isolated modes. To this end, the proposed algorithm takes into account information on the excitation. In addition to the state feedback an additional term, proportional to the earthquake ground acceleration is considered for the determination of the desired active control force. Numerical analyses results demonstrate the efficacy of the above method, especially in improving floor response spectra, and its superiority with respect to clipped-optimal algorithms. [ABSTRACT FROM AUTHOR]

There is a strong need for user-friendly software among urban planners and climatologists in order to develop climatologically conscious urban designs. In this paper we present possibilities (i.e. software packages) for the improvement of outdoor thermal comfort in built urban environments using Universal Thermal Climate Index (UTCI) calculations. For this purpose, automatic algorithms for changing body locations, buildings heights and trees locations in street parking lot areas were developed and applied in the Grasshopper software. The applicability of the algorithms was tested in real-world street parking lot in a Central European city as an example. Temporal analyses were performed during heat wave period in 2015. Outdoor thermal comfort was improved at approximately 66% of body locations during heat wave period. Usage of automatic algorithms in appropriate software showed to be a valuable contribution for urban planning strategies aimed at counterattacking the adverse effects of urban climate and expected climate change (i.e. temperature rise) in cities. [ABSTRACT FROM AUTHOR]

The paper discusses a method for simultaneous localization and identification of vehicles by active visual ID tags - small LED arrays. Lights from ID tags are captured by the standard camera which allows low cost of the overall solution, high flexibility of changing ID if needed and resistance against changes in ambient light. The proposed localization algorithm is capable of detecting not only position but also direction of the vehicle. Algorithm has been implemented in the OpenCV framework and tested on multiple E-puck mobile robotic platforms. Output of the algorithm can be used for real-time navigation of the vehicle inside parking house, applicable for both indoor and outdoor environments. [ABSTRACT FROM AUTHOR]

Evaluation of objective function for problems of structural optimization is generally considered as computationally expensive and can take from few seconds to hours or even days. After certain number of solutions has been evaluated during optimization, artificial neural networks (ANNs) can be trained and used to approximate the objective function. The number of training points depends on the character and topology of objective function, but the most important factor is the dimensionality of objective function. Similarly as the performance of optimization algorithms, requirements on training data for ANNs are affected by so called “curse of dimensionality”. To achieve the same precision of ANN approximation over n-dimensional space, the number of training points grows exponentially with the number of dimensions. This paper presents a feasibility study of using ANNs for approximation of objective function for problems solved by structural optimization with respect to the number of optimization variables. The goal of this study was to find the maximum number of dimensions, where it is feasible to use ANNs for approximation of objective function. Test problem with varying number of optimization variables was used to assess the feasibility of using ANN. [ABSTRACT FROM AUTHOR]

Architecture is mostly perceived as a static, unchanging and rigid element without an ability to react to the changing environment around it and the specific conditions of its location. The digital approach to architectural design has already shown that it is possible to create architectural prototypes that react to the external inputs by changes in their material properties or even in the shape. The conventional, stationary architecture is not able to react to the environmental factors, nor to the changing needs of building occupants, which brings architects, designers, and engineers to the issue of movement in architecture. This paper describes selected adaptive materials and structures used in architecture. An adaptive shape is designed and analyzed using a combination of 3D modeling tool Rhinoceros and the visual algorithmic plug-in Grasshopper, together with the extension for Grasshopper, Kangaroo. The wind simulation is made in the Flow Design. [ABSTRACT FROM AUTHOR]

The results obtained from the numerical simulations of the vehicle-bridge interaction are appreciate sources of information that help to better understand the mechanism how the bridge responses to the moving vehicle. Several commercial computer programs that contain suitable contact algorithm are used for this purpose. Even though, there are often restrictions that define the limits for the simulation especially in the case when the irregularities on the road are treated. The development of the whole program which can solve this problem is difficult so there is good to use some open source applications that requires only some modifications to be used for this purpose. EasyDyn framework is a C++ library which can be used to create a multibody model of a vehicle. Then the development of the algorithm is only reduced to the finite element model of the bridge and the contact algorithm. In the paper there is presented this approach and the results are compared with the results obtained from the commercial software ADINA. [ABSTRACT FROM AUTHOR]

This paper presents new algorithm for sectorisation of a Water Distribution Network (WDN) named Water Network Sectorisation (WNS) algorithm. Algorithm relies on Graph Theory to search for the Strong Connected Components (SCCs) in the graph, that are later on topologically sorted and aggregated in the sectors. Aggregation is driven by engineering criteria and heuristics such as sectors of approximately equal size with smallest number of links connecting them. Interventions in the network are not implemented in order to avoid negative effects on the networks’ hydraulics. This is important especially for primary stages of sectorisation in which preserving hydraulic performance and minimal investment are the main objectives. Methodology is illustrated on a real size WDN. The results obtained show that the WNS algorithm can be used as an effective support tool in engineering practice. [ABSTRACT FROM AUTHOR]

The problem of controlled spacecraft motion in vicinity of asteroids is an important flight dynamics task. Solution of the problem consists of gravitational field simulations and control trajectory scheme defininition. We propose to use the model of single gravity points for motion simulation of a spacecraft in an irregular gravitational field of the Eros 433 asteroid. The equations of spacecraft motion are the corresponding equations of the n-body problem. The motion trajectory can be split into a number of from-point-to-point motion parts. Each part can be considered as a two-point Boundary task. The Authors developed a concept of Boundary problem solution based on the Pontryagin's principle and modified Newton's step-by-step approximation method. The Authors developed a special software for the Boundary problem solutions. A boundary task of the controlled spacecraft's transfer between circular orbits from 200 km to 100 km is presented in the paper. [ABSTRACT FROM AUTHOR]

The objective of this paper is to demonstrate the opportunities of topology optimization applied to additive technology which will permit to design ultra-light structures practically without regard to the technological limits. The article gives a brief historical overview of the mutual influence of structures, materials and manufacturing technologies. The additive technology seems to have the broadest opportunities for producing existing structures using conventional materials without design changes. A hypothetical variable density material provides the means to solve an auxiliary problem of optimal material distribution considering stress or stiffness constraints. The special optimization algorithm allows the optimal topology layout to be found which will have a minimum value of the integral characteristic, called “load-carrying factor” (LCF). The LCF is a powerful tool for estimating the perfection limit of any structural and technological solution. Along with the optimal structure, such solutions are difficult for manufacturing using conventional materials and technologies. A creation of real material with the characteristics of hypothetical material is considered as one of the nearest areas of additive technology's development for finding optimal structures. [ABSTRACT FROM AUTHOR]

Thermal Power plant (TPP) is biggest source of power in India. About 65% of electricity is generated by using thermal power plant. The equipment of TPP runs for 24x7 days through the year. The fault of TPP equipment needs to identify at early stage before the breakdown of system or unit. The maintenance functions of TPP should be optimized carefully by selecting suitable maintenance strategy at least cost. Identification and confirmation of fault in TPP equipment is very important step for decision making. It helps to optimize the maintenance activity. This paper proposes an algorithm for use of co-ordinated condition monitoring approach for identification and confirmation of fault. The objective of this study is to improve the availability and heath of critical equipment of Dahanu Thermal Power Station (DTPS) located in western region of India. [ABSTRACT FROM AUTHOR]

Gearing studies, gear-manufacturing simulations or FEM analysis are nowadays performed mostly in virtual environment. Basically, studies in virtual environment require models, in present cases gear models. The reliability of the results of further studies requires gear models that are built with an adequate precision, and in a shortest possible time too. A shorter modeling time allows numerous rebuilds caused by different parameter changes, profile displacements, tool profile changes or even manufacturing error simulations. Our final goal is to develop a new, simplified gear model generating method, based on the relative movements of the tool(s) and work piece. The generating procedure proposed in the present paper makes possible instantaneous modification of the cutting tool or manufacturing motions without of the use of complicated mathematical formulae – still ensuring a satisfying precision. This pure Computer Aided Design method is intended to work much faster than other usually used gear modeling methods, with a sufficient precision which can be used for any intended further technical or scientific purpose. The authors have developed a points cloud generating and filtering method based on Alpha Shape filtering algorithm. The generating algorithm was completed with arbitrary chosen feed type motions. The initial algorithm was optimized for a faster generating time, with the keeping of the imposed precision. The developed method was used to generate the asymmetrical tooth structure of a helical teethed cylindrical gear. [ABSTRACT FROM AUTHOR]

This paper presents the problem of using simulation modelling - both with a view of assessing the efficiency of online service systems control and improving such efficiency by applying simulation models within the framework of the corresponding control algorithms. In the first case, the model is used in emulation mode when it is used as a tool for creating various situations in servicing environment which interacts with the already used algorithms of dispatching and control. In the second case, the model is used in the real-time mode when it is used as a tool for checking candidate solutions to be taken in a specific on-the-spot situation. A review of literature is presented showing the experience of using simulation models both in emulation mode and in the mode of tracking real-time processes. [ABSTRACT FROM AUTHOR]

Era of knowledge economy, how to effectively mining, the use of knowledge is the enterprise growing concern. CBR system from the field of artificial intelligence is a self-learning system to manage tacit knowledge (case). Case retrieval link is the core link, the advantages and disadvantages of search methods directly affect the efficiency of case retrieval and case matching accuracy. Therefore, this paper proposes a new case matching process: when the size of the case database is small, it searches based on the case similarity algorithm; when the case database is large, it searches based on the FCM secondary retrieval model. And illustrates the fastness and efficiency of FCM in matching large-scale case database. [ABSTRACT FROM AUTHOR]

In this paper, the 6-RSS parallel mechanism is studied to deal with multiple DOF vibration isolation problems of precision control, the active isolation vibration control is investigated. Based on the dynamics model of active isolation vibration system, a Grey Fuzzy Control (GFC) approach is proposed to improve the performance and stability of the 6-RSS parallel mechanism. It proves that GFC is a better design method in the presence of constraints. And the control algorithm utilizes the grey predictive theory to predict the system next-step output response for pre-correction. Simulation results demonstrate the feasibility of the GFC algorithm for real-time implementation. [ABSTRACT FROM AUTHOR]

The world has entered the era of knowledge economy, knowledge is becoming the core of social production. Any organization or individual can only continue to strengthen the application of knowledge, in today's changeable, fast changing, change in the competition to stand out. Provides a rich source of data explosion of information and knowledge for knowledge application, knowledge management research direction of past and existing knowledge, needs the shortcomings, which introduced the large-scale data adapter based on knowledge. Large data sets in the memory not only need to consume a large amount of storage space, but also put forward higher requirements for data retrieval, and the existing search engine is not very good to meet the needs of knowledge adaptation system. Based on large data sets, this paper mainly studies the retrieval system of knowledge adaptation system. The selection of the algorithm for the search engine, the analysis of the deficiencies, and put forward a targeted improvement program-kNN algorithm to increase the pre process, expand the scope of application and effect of the engine. Finally, the efficiency and effectiveness of the model are verified by the example of forest cover. [ABSTRACT FROM AUTHOR]