A Model for Anomaly Detection Using the Metaheuristic Methods

Today detection of new threats has become a need for secured communication to provide complete data confidentiality, integrity and availability. Design and development of such an intrusion detection system in the communication world, should not only be new, accurate and fast but also effective in an environment encompassing the surrounding network. In this paper, a new approach is proposed for network anomaly detection by combining neural network and clustering algorithms. We propose a modified Self Organizing Map algorithm which initially starts with null network and grows with the original data space as initial weight vector, updating neighborhood rules and learning rate dynamically in order to overcome the fixed architecture and random weight vector assignment of simple SOM. New nodes are created using distance threshold parameter and their neighborhood is identified using connection strength and its learning rule and the weight vector updating is carried out for neighborhood nodes. The Fuzzy k-means clustering algorithm is employed for grouping similar nodes of Modified SOM into k clusters using similarity measures. Performance of the new approach is evaluated with standard bench mark dataset. The new approach is evaluated using performance metrics such as detection rate and false alarm rate. The result is compared with other individual neural network methods, which shows considerable increase in the detection rate and 1.5% false alarm rate.

A Hybrid Genetic Algorithm and Sperm Swarm Optimization (HGASSO) for Multimodal Functions

In this paper, we propose a hybrid algorithm combining two different metaheuristic methods, “Genetic Algorithms (GA)” and “Sperm Swarm Optimization (SSO)”, for the global optimization of multimodal benchmarks functions. The proposed Hybrid Genetic Algorithm and Sperm Swarm Optimization (HGASSO) operates based on incorporates concepts from GA and SSO in which generates individuals in a new iteration not only by crossover and mutation operations as proposed in GA, but also by techniques of local search of SSO. The main idea behind this hybridization is to reduce the probability of trapping in local optimum of multi modal problem. Our algorithm is compared against GA, and SSO metaheuristic optimization algorithms. The experimental results using a suite of multimodal benchmarks functions taken from the literature have evinced the superiority of the proposed HGASSO approach over the other approaches in terms of quality of results and convergence rates in which obtained good results in solving the multimodal benchmarks functions that include cosine, sine, and exponent in their formulation.

Large-Scale Truss Topology and Sizing Optimization by an Improved Genetic Algorithm with Multipoint Approximation

Truss size and topology optimization problems have recently been solved mainly by many different metaheuristic methods, and these methods usually require a large number of structural analyses due to their mechanism of population evolution. A branched multipoint approximation technique has been introduced to decrease the number of structural analyses by establishing approximate functions instead of the structural analyses in Genetic Algorithm (GA) when GA addresses continuous size variables and discrete topology variables. For large-scale trusses with a large number of design variables, an enormous change in topology variables in the GA causes a loss of approximation accuracy and then makes optimization convergence difficult. In this paper, a technique named the label–clip–splice method is proposed to improve the above hybrid method in regard to the above problem. It reduces the current search domain of GA gradually by clipping and splicing the labeled variables from chromosomes and optimizes the mixed-variables model efficiently with an approximation technique for large-scale trusses. Structural analysis of the proposed method is extremely reduced compared with these single metaheuristic methods. Numerical examples are presented to verify the efficacy and advantages of the proposed technique.

Assessment of jeans sewing thread consumption by applying metaheuristic optimization methods

PurposeThis work highlights the optimization of the consumed amount of sewing thread required to make up a pair of jeans using three different metaheuristic methods; particular swarm optimization (PSO), ant colony optimization (ACO) and genetic algorithm (GA) techniques. Indeed, using metaheuristic optimization techniques enable industrialists to reach the lowest sewing thread quantities in terms of bobbins per garments. Besides, the compared results of this research can obviously prove the impact of each input parameter on the optimization of the sewing thread consumption per pair of jeans.Design/methodology/approachTo assess objectively the sewing thread consumption, the optimized sewing conditions such as thread composition, needle size and fabric composition are investigated and discussed. Hence, a Taguchi design was elaborated to evaluate and optimize objectively the linear model consumption. Thanks to its principal characteristics and popularity, denim fabric is selected to analyze objectively the effects of studied input parameters. In addition, having workers with same skills and qualifications to repeat each time the same sewing process will involve having the same sewing thread consumption values. This can occur in some levels such as end of sewing, the number of machine failures, the kind of failure and its complexity, the competency of the mechanic and his way to repair failure, the loss of thread caused by threading and its frequency. Seam repetition due to operator lack of skill will obviously affect clothing appearance and hence quality decision. Interesting findings and significant relationship between input parameters and the amount of sewing thread consumption are established.FindingsAccording to the comparative results obtained using metaheuristic methods, the PSO and ACO technique gives the lowest values of the consumption within the best combination of input parameters. The results show the accuracy of the applied metaheuristic methods to optimize the consumed amount needed to sew a pair of jeans with a notable superiority of both PSO and ACO methods compared to experimental ones. However, compared to GA method, ACO and PSO algorithms remained the most accurate techniques allowing industrials to minimize the consumed thread used to sew jeans. They can also widely optimize and predict the consumed thread in the investigated experimental design of interest. Consequently, compared to experimental results and regarding the low error values obtained, it may be concluded that the metaheuristic methods can optimize and evaluate both studied input and output parameters accurately.Practical implicationsThis study is most useful for denim industrial applications, which makes it possible to anticipate, calculate and minimize the high consumption of sewing threads. This paper has not only practical implications for clothing appearance and quality but also for reduction in thread wastage occurring during shop floor conditions like machine running, thread breakage, repairs, etc. (Kawabata and Niwa, 1991). Unless the used sewing machine is equipped within a thread trimmer improvement in garment seam appearance cannot be achieved. By comparing and analyzing the operating activities of the regular lock stitch 301 machine with and without a thread trimmer, a difference in time processing can be grasped (Magazine JUKI Corporation, 2008). Time consumed in trimming by a lockstitch machine without a thread trimmer equals 3.1 s compared to 2.6 s by a thread trimming one. Hence, the reduction rate in the time processing equals 16.30%. This paper aimed to implement the optimal consumption (thread waste outstanding number of trials). Unless highly skilled workers are selected and well-motivated, the previous recommended changes will not be applied. The saved cost of the sewing thread reduction can be used to buy a better quality of fabric and/or thread. However, these factors are not always the same as they can vary according to customer's requirements because thread consumption is never a standard for sewn product categories such as trousers, shirts and footwear (Khedher and Jaouachi, 2015).Originality/valueUntil now, there is no work dealing with the investigation of the metaheuristic optimization of the consumed thread per pair of jeans to minimize accurately the amount of sewing thread as well as the sewing thread wastage. Even though these techniques of optimization are currently in full development due to some advantages such as generality and possible application to a large class of combinatorial and constrained assignment problems, efficiency for many problems in providing good quality approximate solutions for a large number of classical optimization problems and large-scale real applications, etc., are not applied yet to decrease sewing thread consumption. Some recent published works used statistical techniques (Taguchi, factorial, etc.), to evaluate approximate consumptions; conversely, other geometrical and mathematical approaches, considering some assumptions, used stitch geometry and remained insufficient to give the industrialists an implemented application generating the exact value of the consumed amount of sewing thread. Generally, in the clothing field 10–15% of sewing thread wastage should be added to the experimental approximate consumption value. Moreover, all investigations are focused on the approximative evaluations and theoretical modeling of sewing thread consumption as function of some input parameters. Practically, the obtained results are successfully applied and the ACO method gives the most accurate results. On the other hand, in the point of view of industrialists the applied metaheuristic methods (based on algorithms) used to decrease the amount of consumed thread remained an easy and fruitful solution that can allow them to control the number of sewing thread bobbin per garments.

Analyzing metaheuristic methods to build an optimal composite foot prosthesis insole

This paper uses metaheuristic algorithms to develop and optimize composite materials. To calculate the characteristics that allow the planned item to withstand particular loads, ABC and Differential Evolution algorithms are utilized. One of the key challenges in these designs is determining the piece's thickness. Designing a carbon fibre insole for Latin American users will improve the design process by generating functional solutions that are feasible to manufacture and in less time than traditional design methods. The results reported in this work demonstrate that a functional design may be developed, validated by finite element method, with minimal material waste and in a reasonable period.

A new approach to solving multiobjective flowshop scheduling problems: A multi-MOORA-based genetic algorithm

Flowshop scheduling problems constitute a type of problem that is frequently discussed in the literature, where a wide variety of methods are developed for their solution. Although the problem used to be set as a single purpose, it became necessary to expect more than one objective to be evaluated together with increasing customer expectation and competition, after which studies started to be carried out under the title of multiobjective flowshop scheduling. With the increase in the number of workbenches and jobs, the difficulty level of the problem increases in a nonlinear way, and the solution becomes more difficult. This study proposes a new hybrid algorithm by combining genetic algorithms, which are metaheuristic methods, and the Multi-MOORA method, which is a multicriterion decision-making method, for the solution of multiobjective flowshop scheduling problems. The study evaluates and tries to optimize the performance criteria of maximum completion time, average flow time, maximum late finishing, average tardiness, and the number of late (tardy) jobs. The proposed algorithm is compared to the standard multiobjective genetic algorithm (MOGA), and the Multi-MOORA-based genetic algorithm (MBGA) shows better results.

PROSPECTIVE TRENDS OF HARMONIOUS POSSIBILITIES IN OPTIMIZATION OF PRODUCTION SYSTEMS OF CONSTRUCTION

Purpose. Scientific formation of algorithmic support of construction organization and management processes with the use of metaheuristic methods in solving practical problems of optimal control of nonlinear dynamic production systems. Methodology. Use of metaheuristic methods of optimization, system analysis and system substantiation, use of methods of systems theory, use of methods of modeling theory for the purpose of perspective management of production systems of building branch on the basis of the general laws and principles of harmony. Results. The scientific formation of the concept of harmonious optimization of production systems of construction by the metaheuristic method of the golden section is performed. The scheme of work of the method of golden section in optimization problems of construction production is developed and the detailed visualization of this method on levels of symmetry is executed. The ways of application of the principles of harmonious management in the optimization of construction production systems in the direction of sustainable and logical development are substantiated. The components of harmonious production in improving the interaction of different departments and accelerating the response to rapid change, which will accelerate the level of success of any organization. Originality. The concept of harmonious optimization of production systems of construction by metaheuristic method of golden section is offered. The scheme of work of the method of golden ratio in optimization problems of construction production is developed and the detailed visualization of this method on levels of symmetry is executed. Practical value. The use of optimization measures to increase the efficiency of construction production is proposed to be implemented according to the developed basic algorithm for optimizing the functioning of the construction production system according to the concept of the golden ratio method. Conclusions. The substantiation of ways of application of principles of harmonious management in optimization of building production systems in the direction of steady and logical development is executed. The components of harmonious production in improving the interaction of different departments and accelerating the response to rapid change, which will accelerate the level of success of any organization. The result is the creation of all conditions for the harmonious interaction of performers and equipment at all levels of construction management, which confirms the need to develop modern approaches to production on the principles of harmony.

Flexible open-shop problem for minimizing weighted total completion time

In this article, scheduling flexible open shops with identical machines in each station is studied. A new mathematical model is offered to describe the overall performance of the system. Since the problem enjoys an NP-hard complexity structure, we used two distinct metaheuristic methods to achieve acceptable solutions for minimizing weighted total completion time as the objective function. The first method is customary memetic algorithm (MA). The second one, MPA, is a modified version of memetic algorithm in which the new permutating operation is replaced with the mutation. Furthermore, some predefined feasible solutions were imposed in the initial population of both MA and MPA. According to the results, the latter action caused a remarkable improvement in the performance of algorithms.