Network Programming Method Research Articles

Network programming - theory and application to manager building projects

The paper deals with network programming method and its application for solving multi-extreme and discrete optimization problems in Project Management. The purpose of the paper is to develop a new approach to solving optimization problems, called the network programming method and to solve a number of optimization problems of project management based on this method. This method is used to solve the problem of building a business-supporting project portfolio. The life cycle of a building project can be represented as a great number of interrelated and interacting actions leading to the achievement of the set goals in the presence of existing constraints (resources, time, cost, quality, reliability, safety, etc.). Such a representation is called a network representation. On the basis of the network programming method and its special case - the dichotomous programming method, new algorithms for solving a number of optimization problems in project management are proposed. The proposed method makes it possible to use it in solving the problems of managing the life cycle of a construction object. It can be used not only throughout the entire life cycle, but also independently during the planning, implementation and completion phases of project management.

Application network programming method – knapsack problem and it’s modification

New method of multi-extremal optimization has been developed - a network programming method, which is based on the possibility to represent a complex function as a superposition of simpler functions. The paper deals with network (dichotomous) programming method and its application for solving multi-extremal and discrete optimization problems in Project Management. The main goal of the paper is to develop a new approach to solving knapsack problem and to solve a number of optimization problems of project building management. The optimal structure of the dichotomous representation is determined. On the basis dichotomous programming method new algorithm to solve a optimization problem is proposed

A secure drone-to-drone communication and software defined drone network-enabled traffic monitoring system

This paper proposes a novel lightweight security-enabled distributed software-defined drone network (SDDN) for traffic monitoring. Security of drone/Unmanned Aerial Vehicles (UAV) communication and data exchange is ensured through lightweight key generation and encryption/decryption algorithm. A hybrid (static and dynamic) OpenMP/MPI-based distributed processing is used to compute the security primitives for drone-to-drone communication. The proposed approach is more reliable, scalable and interoperable compared to other centralized logical control and incorporating network programming methods. Additionally, the use of cryptographic primitives and protocols make it more secure against attacks. A comparative analysis of proposed lightweight key generation and encryption/decryption algorithms with state-of-the-art algorithms shows that both proposed algorithms require fewer Gate Equivalents (GEs), and it varies from 18.4k to 29.6k. In terms of performance, both algorithms’ computational delay varies from 1.5 to 2 s. Jitter lies between 0.7 msec and 2 msec. The proposed algorithms are found to have communicational costs varying with 0.4 and 0.7 times of input in bytes with a base value of 1.4 and 1.25. Further, energy consumption is varying with 0.4 and 0.7 times of input in bytes with a base value of 0.3 and 0.25. Security interruption probability variation analysis show that the proposed security algorithms are better compared to state-of-the-art approaches. Further, security analysis of both algorithms (using a statistical and formal model) shows that the proposed system is protected against various attacks.

Primena teorije mrežnog programiranja za formiranje portfolia projekta

The paper deals with an application of the network (dichotomous) programming method for solving multi-extremal problems and discrete optimization problems. The concept of a generalized dual problem is introduced and a theorem on its convexity is proved. Network programming method is used to build a business-forming project portfolio as well as an algorithm for solving completely dependent related projects is developed. Also, this method is used to solve the problem of building a business-supporting project portfolio for which the lower cost estimate is obtained. A computational experiment is carried out to evaluate the suggested algorithm, which showed that for large dimensions of the problem it is more effective than for solving the problem by linear programming methods.

The Network Programming Method in Project Scheduling Problems

The network programming method is applied to the discrete problem of minimizing the costs of a project with a given duration. Two basic algorithms for solving this problem in the cases of independent and sequential jobs are described. More complex cases of project scheduling on networks (tree network and aggregated network) are treated by the sequential application of the basic algorithms. For the case of a build-up assembly network, a new method based on the following idea is proposed: an appropriate set of jobs is determined and their durations are fixated so that the resulting network becomes either a tree or an aggregated network. All possible alternatives for fixating the durations of jobs from such a set are considered and, for each alternative, the problem is completely solved. The best alternative among all possible ones is selected. The case of project scheduling on an arbitrary network is also studied.

Models and mechanisms for planning service improvements

Models and mechanisms for project portfolio management, constantly generated by the IT service provider and designed to optimize IT processes of IT service life cycle stages are the subject of this article. The service improvement plan is formed from the project portfolio and is aimed at achieving critical indicators of IT services market success relevant for the current period. Two linear and one nonlinear models of the problem of forming a service improvement plan were considered. The criteria chosen for task optimization are absolute and relative value of the complex IT process efficiency indicator. Problems take into account the investment costs on implementing projects and changing the operational costs on functioning of optimized IT processes. All the problems were solved with the use of network programming methods.

Planning a Research Process in Security Sciences Through Methods of Operational Research

This article presents fundamental issues related to the process of planning scientific research in security sciences based on methods belonging to operational research. Operational research is one of the areas that are intensively developed and implemented towards security and performance improvement in areas such as planning, organizing, implementing or controlling various types of projects. Therefore, issues related to operational research, its methodological foundations, and the use of network programming methods in the field of planning research process required a broader explanation in the context of security sciences. As a consequence, a reference to the decision model was made. It was stated that each decision related to security research increases the demand for methods of analysis and objective assessment. Each undertaking, in particular this related to security research, is associated with specific goals, the achievement of which requires possession of appropriate forces and resources. This study refers to the essence of project implementation time, which is very often limited and can be used in a variety of ways, which is determined by the specific conditions in which the technical, organizational or other activities are carried out. As a consequence of the above, it is stated that the research process is characterized by conducting a sequence of activities aimed at achieving research goal, solving research problem or verifying hypothesis within a specified time frame. It is also stated that each research process has a specific duration and one can be tempted to state that it is usually unique.

The mechanism for the generalized dual problem of network programming solving

The generalized dual problem (GDP) is formulated as a search task of the upper bound minimum (lower bound maximum) for the optimum obtained by solving discrete linear and nonlinear problems by the network programming method. The need for GDP solution arises when, in order to meet the applicability conditions of the method, the right side of the constraint is divided into several unknown summands. The GDP consists in finding of such a partition that ensures achievement of corresponding minimum (maximum). There is no evidence for an existence of the GDP solution for today. However, the conditions for the GDP optimum solution have been formulated. The article proposes an iterative mechanism for search solution of the generalized dual problem. This mechanism is based on the software implementation of the procedure for solving the optimization problem by means of network programming. The application of the mechanism is illustrated on the developing competences task of IT services users. It was shown that the GDP solution exists and is not the only one.

Development of training programs for users of enterprise resource planning system

One of the important factors (may be, the main one) determining duration of initial (trial) operation of Enterprise Resource Planning (EPR) is quality of users training to collaboration in integrated (at the level of elementary transactions) control system. It is obvious that duration of initial operation and corresponding losses from the incidents arising at EPR operation can be significantly reduced not only due to high-quality design and EPR testing, but, considerably, due to increase in level of competences of users reached by their training. Mathematical definition of training program development for EPR users of large metallurgical company is given in the article. The main criterion there is general increment of users’ competences as a result of implementation of training program. Procedure of task solution is based on method of network programming which relies on structural and similar network representation of criterion and restrictions. General scheme and an example of solution of the studied task are provided in which separate estimated tasks are solved by method of dichotomizing programming. Received approximate solutions of an objective can be improved by means of finding global optimum of initial task by method of branches and borders in which values of criterion function of found approximate decision are applied as borders. In practice it is expedient to consider a task, opposite to described in the article in which costs of training are the criterion. Owing to structural similarity of functions of an increment of competences and costs of training the return task can be decided according to the same scheme that it is offered for a direct task. The considered task can be generalized by taking into account the preferences of users regarding the significance of individual programs relative to others by introducing appropriate “scales”. General scheme of task solution won’t change.

About the mechanism of ERP-system pilot test

In the paper the mathematical problem of defining the scope of pilot test is stated, which is a task of quadratic programming. The procedure of the problem solving includes the method of network programming based on the structurally similar network representation of the criterion and constraints and which reduces the original problem to a sequence of simpler evaluation tasks. The evaluation tasks are solved by the method of dichotomous programming.

A league championship algorithm equipped with network structure and backward Q-learning for extracting stock trading rules

Buying and selling stocks are the main activities of investment in the financial markets. During several years, financial experts have designed various indices and indicators to develop intelligent methods to decide whether buy or sell or no trade a specific stock. In this paper, the league championship algorithm (LCA) is adapted and equipped with a network structure (which provides the implicit memory function, compact structure and gives the ability of reusing nodes) for stock trading rule extraction process. The proposed algorithm is able to extract and save various stock trading rules for various kinds of stock market conditions. Each individual in LCA makes role as a sport team which could learn from weaknesses and strengths of others to enhance its performance. The network structure used for each individual is equipped with reinforcement learning to strength the searching power and extracting better rules. The backward Q-learning (BQL), which is a combination of Sarsa learning and Q-learning algorithms, is also hybridized with LCA to increase the learning speed to extract better rules. A trend clustering technique is also developed to determine uptrends and downtrends and to remedy delay in the trend direction reflection along with moving average of stock prices. Finally, to use the trading rules extracted and saved in the rule pools, a new approach through average matching degree is introduced which could create trinary signals of buying, selling, and no trade. The effectiveness of the proposed approach is tested on a set of 20 companies, which have high liquidity and large market capitalization, chosen from various fields of Tehran Stock Exchange. The used historical price data was adjusted through factors of dividends and capital increase. Computational tests and simulations indicate that our hybrid method clearly offers higher profits and lower losses than those of genetic network programming method with rule accumulation (GNP-RA) on all stocks and those of the Buy&Hold strategy on 17 out of 20 instances (85%), especially when the price uptrends are sharp.

Задача равномерного распределения требований по узлам вычислительной сети

The tasks of computing organizations in computer networks have become very popular lately. This is the scheduling of solving many problems on a single computer network and various tasks of loading nodes of the computer network. The article deals with the problem of uniform loading of nodes of the computer network. As a criterion, the maximum relative loading of nodes by the amount of memory is taken. The problem is generalized to the case of two criteria. Heuristic algorithms for solving problems are offered, which favorably differ from the algorithm of branches and boundaries used earlier to obtain estimates based on the method of network programming. With a large number of requirements, this method of obtaining estimates leads to a large amount of computation, since obtaining estimates requires, at each step, solutions of systems of linear inequalities.

Задачи и методы повышения уровня зрелости организации в области управления проектами

The article considers the task of the organization's maturity level increasing on the convergence mechanisms basis. The essence of these mechanisms in the transfer of effective elements of various methodologies of project, programs and project portfolios management (best practices) to the methodology of project, programs and project portfolios management of the organization to improve its maturity level in the field of project management. The article presents the formulation and methods for solving the problem of the methodological elements optimal to increase the level of organizations maturity with minimum expenditure of funds and (or) time. The first task is to select m elements of the methodology with a minimal cost of increase their value to the required level. The second task is also to choose the m elements of the methodology in the presence of two criteria: the time of adaptation of new elements and the cost of their adaptation. The problem is reduced to the previous one based on a linear convolution of the criteria. Finally, the third task is to minimize one of the criteria (for example - time) while another criterium is limited. The Lagrange multipliers method is proposed to solve this problem. This method either gives an approximate solution, or - an estimate for the initial problem, which can be used in the method of branches and boundaries. A different algorithm of estimates obtaining based on the network programming method (I.V. Burkova) is also proposed. The essence of the method consists in splitting the costs of adapting each element into two parts. We obtain two evaluation problems. The sum of optimal values of these problems gives us an upper bound for the original problem. The problem of finding the optimal partition is called a generalized dual problem, which is the problem of convex programming. Optimality conditions for solutions of the direct and generalized dual problems are obtained. Using computer experiments, the advantage of the network programming method is shown.

Robust phase unwrapping for phase images in Fourier domain Doppler optical coherence tomography.

To solve the 2 ? phase ambiguity for phase-resolved Doppler images in Doppler optical coherence tomography, we present a modified network programming technique for the first time to the best of our knowledge. The proposed method assumes that error of the discrete derivatives between unwrapped phase image and wrapped phase image can be arbitrary values instead of integer-multiple of 2 ? , which makes the real-phase restoration accurate and robust against noise. We compared our proposed method with the network programming method. Parameters including root-mean-square-error and noise amplification degree were adopted for comparison. The experimental study on simulated images, phantom, and real-vessel OCT images were performed. The proposed method consistently achieves optimal results.

FORMATION OF FUNCTIONAL VOLUME AND WORKING GROUPS OF ERP-PROJECT OF THE ENTERPRISE

Critical in the creation of ERP-system of the enterprise is the first stage of the system. Simultaneous introduction of all services for all business processes of the enterprise, as a rule, isn’t possible or expedient for various reasons: lack of sufficient resources, difficulties of creation of necessary technical infrastructure in short terms, big risks of radical reorganization of the operating control system, etc. Therefore, the functional volume of the 1st turn of the project joins the IT services providing effective functioning of the most interconnected business processes. The paper presents a mathematical formulation and procedure for solving the problem of determining the portfolio of IT services that realize the functions of the main business processes and make up the functional volume of the first stage of the ERP system of a large metallurgical company. Problem definition considers three important indicators of efficiency of the ERP-project: size of the project budget, number of communications between the IT services making the functional volume of the project (its “integration kernel”), number of the inherited design decisions from the systems of a “scrappy” computerization finding application in the enterprise resource planning. The first of these indicators is accepted as criterion of a task, other two – as its restrictions. As a result of formalization, the problem under consideration reduces to the problem of integer-valued quadratic programming. The method of network programming in modification used for the solution of nonlinear programming problems of is applied for its decision. The method decomposes a complex initial problem into a generalized dual task of network programming and a set of essentially simpler subtasks. An example is given of the solution of the problem under study in which the generalized dual problem of network programming is solved by the method of Lagrange multipliers, and individual subtasks are solved by the method of dichotomous programming, which reduces the solution of subproblems to the solution of a sequence of simple estimation problems. The solution of the task of forming a portfolio of services delivers the initial data for the task of scheduling the implementation of services by project groups responsible for the computerization of individual business processes of the enterprise.

Nonlinear optimization problem of interdependent investment projects portfolio

The optimal portfolio problem of effect-interdependent investment projects is considered. An algorithm yielding the optimal solution based on the method of network programming is suggested. The performance of this algorithm is illustrated using an example.

Задачи оперативного управления проектами

We consider the problems of operational management of projects. The tasks are to reduce the completion date of the project to the desired value with minimal cost. It is assumed that for each job there is the variant of reducing its duration. An efficient algorithm for solving the problem for the case when cost functions are discrete, for a network graph with tree view, and for the aggregated networks is suggested. Theorems about necessary and sufficient conditions in order that the network graph has been aggregated, about the lower evaluation for the original problem and the reduction of the problem of the variables choice maximized the lower bound to the problem of convex programming are proved. For the general case of the method of branches and borders with obtaining of the estimates based on the method of network programming is suggested.

Wireless Network Based Image Transmission between Heterogeneous Operating System

This paper presents the video image acquisition, transmission and display using wireless Internet network between two heterogeneous operating systems. First of all, the design of video acquisition system is designed. Based on V4L2 standard, the video acquisition program is devised. Secondly, by using the method of network programming, the design of network communication is completed based on TCP socket. Finally, based on OpenCV database, the image display interface is realized using MFC technology. The experiment shows that the designed system can realize image transmission between two different operating systems.

The network programming method in control over target programs

We consider the problem of optimizing programs with respect to cost. The state of a program is defined via several goals (criteria) based on a complex evaluation system. For each goal, there exist several projects that contribute to achieving this goal. A number of projects contributes to several goals (multipurpose projects). To solve the problem, we propose two methods. One is based on enumerating all possible ways to include multipurpose projects into the program. The other is based on a network programming technique. We give results of numerical experiments that compare these approaches.

A method of network programming in problems of nonlinear optimization

A method of network programming for solving problems of nonlinear optimization is used. A notion of dual problem is introduced. It is proved that a dual problem is a problem of convex programming. Necessary and sufficient conditions for optimality of dual problem of integer linear programming are obtained.