Dynamic Continuous Processes Research Articles

Optimal Timing Selection Approach to Moving Target Defense: A FlipIt Attack-Defense Game Model

The centralized control characteristics of software-defined networks (SDNs) make them susceptible to advanced persistent threats (APTs). Moving target defense, as an effective defense means, is constantly developing. It is difficult to effectively characterize an MTD attack and defense game with existing game models and effectively select the defense timing to balance SDN service quality and MTD decision-making benefits. From the hidden confrontation between the actual attack and defense sides, existing attack-defense scenarios are abstractly characterized and analyzed. Based on the APT attack process of the Cyber Kill Chain (CKC), a state transition model of the MTD attack surface based on the susceptible-infective-recuperative-malfunctioned (SIRM) infectious disease model is defined. An MTD attack-defense timing decision model based on the FlipIt game (FG-MTD) is constructed, which expands the static analysis in the traditional game to a dynamic continuous process. The Nash equilibrium of the proposed method is analyzed, and the optimal timing selection algorithm of the MTD is designed to provide decision support for the selection of MTD timing under moderate security. Finally, the application model is used to verify the model and method. Through numerical analysis, the timings of different types of attack-defense strategies are summarized.

Physical Simulation Experimental Study on Fault Activation based on Total Station Polar Coordinate Method

Based on the observation principle of total station polar coordinate method, this paper studies the development rule of the fault zone fracture when the working face is pushed from the footwall to the normal fault, and analyzes the fault activation sequence, time and slippage of different fault layers. The results show that the facture firstly generates at the high-level of the fault, gradually develops to the low-level and eventually connects to the gob. In the meantime, the fracture experiences the process from scaling to decreasing to closing. Fault activation is a dynamic continuous process that occurs firstly at the high-level, and gradually develops to the low-level, eventually spreads to the whole fault. The footwall strata subsidence is larger than the hanging wall’s. The fault slipping tendency is similar to the footwall subsiding tendency. The footwall strata migrate more violently than the hanging wall. The fault begins to activate when the distance between the working face and the fault (L0) is 50 m. The fault activation mainly occurs at the high and middle levels when L0 is larger than 20 m, but the low-level activation is primary when L0 is less than 20 m. The fault slippage is the largest when L0 is less than 10 m where the fault activates violently. Therefore, the control of the low-level activation disasters should be strengthened.

Formation of bachelor architects’ creative thinking

The purpose of the article is to characterize the basic methods and principles of forming the creative thinking of bachelors in the process of studying visual disciplines at the Faculty of Architecture of the National Academy of Fine Arts and Architecture, focused on the development of educational and professional activities of future architects. The methodology of the research is to apply analytical, comparative and systematic methods of research for the formation of bachelors-architects‘ creative thinking by means of visual training. To achieve the stated goal and to solve the tasks, the analysis of scientific and methodological sources, normative documents, a generalization of scientific and pedagogi- cal experience on the issues of professional training of future architects has been used. The scientific novelty of the study is that it is the first attempt of a systematic analysis of the study of the development of future architects‘ creative thinking in the process of studying visual disciplines, which is based on a personally oriented approach, namely: the use of methods and techniques of pedagogical influence in accordance with the creative possibilities of students in order to ensure their personal development; the concept of students‘ creative thinking as a dynamic continuous process of indi- vidual properties modification of professional qualities together with professional visual abilities, which takes place during active educational and creative activity is specified. Conclusions: on the basis of the scientific and methodologi- cal analysis of work on the research, the potential of professional disciplines in the development of bachelor-architects‘ creative thinking is revealed; it relies on the fact that productive educational activity requires the intensification of the corresponding psychological processes, in turn, it stimulates the development of creative abilities of the person neces- sary for this activity. It is specified that creative thinking is an individual-psychological feature associated with gifted- ness, creativity, creative potential and other creative qualities of the individual.

A Demand Response Strategy for Continuous Processes Using Dynamic Programming Approach

This work considers the problem of optimizing the energy management in the operation of dynamic continuous processes subject to demand response objectives. A dynamic programming approach that aims to lower the operating cost is developed and presented. The dynamics of process transition between operating modes, as well as the time-sensitive energy profiles, are incorporated into the optimization formulation. The merits of the proposed approach are demonstrated using a jacketed continuous stirred tank reactor where the energy required is assumed to be proportional to the material flow.

Towards Improved Analysis Methods for Two-Level Factorial Experiments with Time Series Responses

Dynamic processes exhibit a time delay between the disturbances and the resulting process response. Therefore, one has to acknowledge process dynamics, such as transition times, when planning and analyzing experiments in dynamic processes. In this article, we explore, discuss, and compare different methods to estimate location effects for two-level factorial experiments where the responses are represented by time series. Particularly, we outline the use of intervention-noise modeling to estimate the effects and to compare this method by using the averages of the response observations in each run as the single response. The comparisons are made by simulated experiments using a dynamic continuous process model. The results show that the effect estimates for the different analysis methods are similar. Using the average of the response in each run, but removing the transition time, is found to be a competitive, robust, and straightforward method, whereas intervention-noise models are found to be more comprehensive, render slightly fewer spurious effects, find more of the active effects for unreplicated experiments and provide the possibility to model effect dynamics. Copyright © 2012 John Wiley & Sons, Ltd.

Variable reconstruction and sensor fault identification using canonical variate analysis

The detection and identification of faults in dynamic continuous processes has received considerable recent attention from researchers in academia and industry. In this paper, a canonical variate analysis (CVA)-based sensor fault detection and identification method via variable reconstruction is described. Several previous studies have shown that CVA-based monitoring techniques can effectively detect faults in dynamic processes. Here we define two monitoring indices in the state and noise spaces for fault detection and, for sensor fault identification, we propose three variable reconstruction algorithms based on the proposed monitoring indices. The variable reconstruction algorithms are based on the concepts of conditional mean replacement and object function minimization. The proposed approach is applied to a simulated continuous stirred tank reactor and the results are compared to those obtained using the traditional dynamic monitoring technique, dynamic principal component analysis (PCA). The results indicate that the proposed methodology is quite effective for monitoring dynamic processes in terms of sensor fault detection and identification.

GAME CONTROL OF MOVING OBJECTS

The paper describes the application of elements of the game theory for the purpose of optimal control of some dynamic continuous processes. Using as an example the process of safe ship's control, the paper presents the problem of applying a positional noncooperative game and multi-step matrix game of j objects for the description of the process considered as well as for the synthesis of optimal strategies. A mathematical model of dynamic game is formulated and its approximation in the form of dual linear programming problem is used for the synthesis of safe ship's trajectory as a multistage process decision. The considerations have been illustrated an example of a computer simulation the POSGAME and RISKGAME algorithms to determine the safe ship's trajectory in situation of passing a big number of the objects encountered, recorded on the radar screen in real navigational situation at sea.

Positional Game Control of Ship in Collision Situations

The paper concerns the application of elements of the game theory for the purpose of optimal control of some dynamic continuous processes. Using as an example the process of safe ship's control, the paper presents the problem of applying a positional noncooperative game of "j" objects for the description of the process considered as well as for the synthesis of optimal strategies. A mathematical model of differential game is formulated and its approximation in the form of linear programming problem is used for the synthesis of safe ship's trajectory as a multistage process decision. The considerations have been illustrated an example of a computer simulation the POSGAME programme to determine the safe ship's trajectory in situation of passing a big number of the objects encountered, recorded on the ship's radar screen in real navigational situation at sea.