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In this paper, we try to apply the advantages of principal component analysis (PCA) and online learning to the calculation of optimal portfolio investments. Each of these methods is widely used separately. This is done in order to make it possible to use online learning algorithms for high-dimension portfolios., Author(s): G. Beliavsky [sup.1], N. Danilova [sup.1], K. Yao [sup.1] Author Affiliations: (1) https://ror.org/01tv9ph92, grid.182798.d, 0000 0001 2172 8170, Operations Research, Mathematics, Mechanics and Computer Sciences Institute of Southern Federal [...]

This article analyzes the role of structural equation modeling in the field of management science. The approach by which the use of the technique is incorporated into the field of management. Additionally, a comparison is generated between the different algorithms and statistical packages available for the application of the technique. Finding in closed source, LISREL, EQS, AMOS, SmartPLS, Mplus, CALIS (in SAS), SEPATH (in Statistica), RAMONA (in Systat), SEM (Stata), Matlab, Semopy (in Python). And in open source: Scilab, Julia, R: lavaan, sem, lava, OpenMx, Strum. Identifying current trends and future approaches that embody the multivariate analysis technique within the management sciences. Finding suggested software for the area of management sciences, as well as mixing trends in the technique, such as the use of neural networks that is beginning to be incorporated as an alternative or complement to the SEM technique. [ABSTRACT FROM AUTHOR]

The key to the in-depth management of science and technology is to model the behavior characteristics of scientific and technological personnel and then find groups by analyzing the diverse associations among them. Aiming at the analysis of team relationship among scientific and technological personnel, this paper proposed a method to recognize the group of scientific and technological personnel based on relational graph. The relationship model of scientific and technological personnel was designed, and based on this, the entity and relationship recognition and extraction are performed on the structured and unstructured source data to construct a relational graph. An improved frequent item mining algorithm based on Hadoop was proposed, which enabled getting the group of scientific and technological personnel by mining and analyzing the data in the relational graph. In this paper, the proposed method was experimented on both open and private datasets, and compared with several classical algorithms. The results showed that the method proposed in this paper has a significant improvement in execution efficiency. [ABSTRACT FROM AUTHOR]

Finding the shortest path of the traveling salesman problem (TSP) is a typical NP-hard problem and one of the basic optimization problems. TSP in three-dimensional space (3D-TSP) is an extension of TSP. It plays an important role in the fields of 3D path planning and UAV inspection, such as forest fire patrol path planning. Many existing studies have focused on the expected length of the shortest path of TSP in 2D space. The expected length of the shortest path in 3D space has not yet been studied. To fill this gap, this research focuses on developing models to estimate the expected length of the shortest path of 3D-TSP. First, different experimental scenarios are designed by combining different service areas and the number of demand points. Under each scenario, the specified number of demand points is randomly generated, and an improved genetic algorithm and Gurobi are used to find the shortest path. A total of 500 experiments are performed for each scenario, and the average length of the shortest path is calculated. The models to estimate the expected length of the shortest path are proposed. Model parameters are estimated and k-fold cross-validation is used to evaluate the goodness of fit. Results show that all the models fit the data well and the best model is selected. The developed models can be used to estimate the expected length of the shortest path of 3D-TSP and provide important references for many applications., Author(s): Hongtai Yang [1]; Xiaoqian Lu [1]; Xinan Zhou [1]; Rong Zheng [1]; Yugang Liu (corresponding author) [1]; Siyu Tao [1] 1. Introduction The traveling salesman problem (TSP) is a [...]

We propose a quantum branch-and-bound algorithm based on the general scheme of the branch-and-bound method and the quantum nested searching algorithm and examine its computational efficiency. We also compare this algorithm with a similar classical algorithm on the example of the travelling salesman problem. We show that in the vast majority of problems, the classical algorithm is quicker than the quantum algorithm due to greater adaptability. However, the operation time of the quantum algorithm is constant for all problem, whereas the classical algorithm runs very slowly for certain problems. In the worst case, the quantum branch-and-bound algorithm is proved to be several times more efficient than the classical algorithm. Keywords and phrases: quantum computing, quantum computer, quantum search, Grover's algorithm, branch-and-bound method, travelling salesman problem. AMS Subject Classification: 81P68, 68Q12, 1. Introduction 2. Branch-and-Bound Method 3. Generalized Grover Algorithm 4. Quantum Branch-and-Bound Method 5. Application of the Quantum Branch-and-Bound Method to the Solution of the Travelling Salesman Problem 6. Conclusion [...]

On‐demand service firms secure market power by cultivating and operationalising calculative asymmetries between the platform and labour. In this article, I analyse dynamic (or 'surge') pricing as an exemplary calculative technique. I show how the asymmetrical application of price‐setting allows firms to leverage control at the aggregate level while maintaining the façade of autonomy at the individual level, thereby legitimising workers' classification as independent contractors but solving the coordination problems that the classification introduces. The article complements and extends previous critical research into the platform or 'on‐demand' service economy by analysing how management scientists model and simulate on‐demand marketplaces. I consider management science to be a calculative technique for optimising operational efficiency. A critical review of management science provides novel insights into platforms' efforts to monopolise calculative agency at the expense of other market participants. The article concludes by considering implications for broader critiques of platform labour management. [ABSTRACT FROM AUTHOR]

This paper proposes a new idea, namely genetic algorithms with dominant genes (GADG) in order to deal with FMS scheduling problems with alternative production routing. In the traditional genetic algorithm (GA) approach, crossover and mutation rates should be pre-defined. However, different rates applied in different problems will directly influence the performance of genetic search. Determination of optimal rates in every run is time-consuming and not practical in reality due to the infinite number of possible combinations. In addition, this crossover rate governs the number of genes to be selected to undergo crossover, and this selection process is totally arbitrary. The selected genes may not represent the potential critical structure of the chromosome. To tackle this problem, GADG is proposed. This approach does not require a defined crossover rate, and the proposed similarity operator eliminates the determination of the mutation rate. This idea helps reduce the computational time remarkably and improve the performance of genetic search. The proposed GADG will identify and record the best genes and structure of each chromosome. A new crossover mechanism is designed to ensure the best genes and structures to undergo crossover. The performance of the proposed GADG is testified by comparing it with other existing methodologies, and the results show that it outperforms other approaches. [ABSTRACT FROM AUTHOR]

This correspondence corrects an algorithm by Huang et al. [International Journal of Production Research, 2001, 39, 283-305] that is used in the development of a deadlock prevention policy for a class of flexible manufacturing systems (FMS) where deadlocks are caused by unmarked siphons in their Petri net models. The algorithm was initially designed to derive a minimal siphon from a maximal unmarked siphon that can be obtained due to the MIP (Mixed Integer Programming)-based deadlock detection method. Also, some minor mistakes detected in the same paper are corrected. [ABSTRACT FROM AUTHOR]

We present an ant-based algorithm to solve multi-level capacitated lot-sizing problems. We apply a hybrid approach where we use the ant system to optimize the decomposition of the problem into smaller subproblems. These subproblems, containing only a few items and periods, are solved using CPLEX. Then the overall solution is derived by consolidating the partial solutions. This hybrid approach provides superior results with respect to solution quality in comparison with the existing approaches in the literature. §This research emerged from the PhD thesis of Rapeepan Pitakaso during his stay at the University of Vienna. [ABSTRACT FROM AUTHOR]

This paper addresses timing constraints' optimization for tasks in a single resource reserved by negotiation in agent-based distributed shop-floor scheduling. The proposed algorithm finds an optimal schedule that meets all the timing and other constraints, where timing constraints such as release times and deadlines are determined in advance through bidding-based production reservation. Even if the algorithm is terminated prematurely, it would still provide a complete schedule that is at least as good as any schedule currently obtained. Furthermore, it assists in managing unpredicted events by increasing marginal time space between the expected completion time of a task and its deadline. [ABSTRACT FROM AUTHOR]

Analytical methods have been proposed in the literature for performance evaluation of kanban control systems. Among them, the method presented by Di Mascolo and colleagues appears to be of special interest since it can handle manufacturing stages consisting of any number of machines and it is fairly accurate. This paper presents a new way of deriving the analytical method presented by Di Mascolo et al. The approach is to see the queueing network of the kanban control system as a multiclass queueing network in which each kanban loop is represented by a class of customers. This allows one to use the general technique proposed in Baynat and Dallery for analysing multiclass queueing network using product-form approximation methods. In terms of equations, the new method is equivalent to that previously presented. However, the computational algorithm is much more efficient since it avoids the two levels of iterations involved in the original algorithm. Another major advantage of the new method over that originally proposed is that it provides a general framework for the analysis of more general kanban systems. Indeed, it is shown in this paper how this approach can easily be extended in order to handle kanban systems with multiple consumers and multiple suppliers, kanban-controlled assembly systems and generalized kanban systems. [ABSTRACT FROM AUTHOR]

Flexible configuration of manufacturing facilities is a key strategy for efficiently improving market responsiveness and market share in the face of uncertain future product demand. Flexible facility configurations can produce an efficient production system that allows higher capacity utilization given uncertainty in product demand and mix. The aim of this paper is to consider the alternative choices of flexible equipment available at the strategic planning level and to make decisions about the facility design and configuration that best suits the specific needs of the manufacturing system under consideration. A chance constrained mixed integer programming model for strategic configuration and capacity planning of flexible multiple-stage production facilities under time-varying production requirements is introduced in this paper. It is an integrated model that determines the number of assembly lines required, the flexible automation levels required in each line, capacity levels, and product assignments/reassignments for a multiple-stage production system, considering the stochastic nature of the demand. A two-step heuristic based on genetic algorithms is proposed and tested. Experimental results indicate that the two-step heuristic performs well in terms of both computation speed and solution accuracy. [ABSTRACT FROM AUTHOR]

Analysis of human judgment and decision making provides useful methodologies for examining the human decision process and substantive results. One such methodology is a lens model analysis. The authors used such a model to study how well a model of expert decisions can capture a valid strategy in the decision process. The study also addresses whether a model of an expert can be more accurate than the expert. The predictive accuracy (predictive validity) of two linear (statistical) models and two nonlinear models of human experts is compared. The results indicate that nonlinear models can capture factors (valid nonlinear strategy) that contribute to the experts' predictive accuracy. However, linear models cannot capture the valid nonlinear strategy as well as nonlinear models. One linear model and two nonlinear models performed as well as the overall average of a group of experts. However, all of the models were outperformed by the most accurate expert. By combining validity of decision strategy with characteristics of modeling algorithms, it is possible to explain why certain algorithms perform better than others. [ABSTRACT FROM AUTHOR]

Among operation research problems, there exist practical problems that can be formulated as network models. Of the results of research of previous years, more than half of the problems on mathematic programming can be realized via network modeling. One of the important problems of network modeling is finding the shortest distance and its realization on a computer. Unlike the known algorithm of finding the shortest distance when we must adopt the formal sum [U.sub.1] =0 and minimizing sum on the following integrations, in the case discussed in this work we maximize the multiplication product and accordingly in the beginning we adopt the formal multiplication product of [U.sub.1] = 1. In this work, one problem is solved via two different forms and methods, and an example of its corresponding realization on computer is provided., UDC 519.7 Among operation research problems, we often meet practical problems that can be formulated as network models. As of the results of research of previous years, more than half [...]

The article presents abstracts of dissertations related to management. They include "Management of Multi-Industry (Conglomerate) Corporations: An Investigation of Decision-Making at the Division Level," "An Efficient Allocation of General Hospital Facilities in Rural Areas: A Computer Algorithm Methodology," and "Management of Learning for the Learning of Management." [ABSTRACT FROM AUTHOR]

The bipartite traveling tournament problem (BTTP) is an NP-complete scheduling problem whose solution is a double round-robin inter-league tournament with minimum total travel distance. The 2n-team BTTP is a variant [...]