The objective of this research was to examine the relationships of the five key foreign tourist markets in the Greater Mekong Sub-region (GMS), Cambodia, Laos, Myanmar, Thailand, and Vietnam. Quarterly data of tourist numbers from China, Japan, Korea, Malaysia, and the USA who traveled to the countries in GMS during the period 2001-2017 were used. Vector Autoregressive (VARs) was used to test Granger Causality to explain the relationships among tourist markets in the region. The findings revealed that tourist markets in Cambodia had forward relations with Laos and Vietnam. Those in Laos had forward relationship with Myanmar and Thailand. Tourist markets in Myanmar had forward relationship with Vietnam, Laos, and Thailand. Tourist markets in Thailand had forward relationship with Vietnam, Laos, and Myanmar whereas those of Vietnam had forward relationship with Laos, Myanmar, Thailand, and Cambodia. The overview shows that the key tourist markets in each country supported each other.

Evaluation of the software usability as concerns software alternatives represents a typical Multi-Criteria Decision-Analysis (MCDA) problem. Such a kind of problem can be successfully faced via structured models and approaches which validity have been widely shown in literature. In this work, a methodological framework based on a MCDA model integrating the DEMATEL method along with the ANP technique is proposed and explained with more detail to address the relevant issue of the software usability evaluation. The applicability of the considered DEMATEL-ANP (DANP) based model in the under analysis contest is demonstrated via a preliminary investigation, where the usability of the two major Mobile Operating Systems (MOSs) is compared and quantitatively prioritized. Results of both performed comparison method and sensitivity analysis confirm the validity of the proposed MCDA model as well robustness of its outcomes. Moreover, results obtained point out about the influenced, independent and core factors for the MOSs usability, as well as strengths, weaknesses and discrepancies in the usability as concerns the two investigated alternatives. Representing these outcomes crucial aspects for driving focused MOSs usability improvement processes and strategies, they give also evidence of the effectiveness of the proposed methodological framework.

Agri-food supply chains have received the attention of many researchers in recent years for various reasons, including food security and health-related issues. Wheat, as a staple food in many countries, is the most cultivated crop in the world. Due to the importance of wheat, this paper proposes a mixed-integer linear mathematical model for redesigning and planning of the wheat supply chain. The proposed model determines the location and capacity of new storage facilities while addressing supplier selection, ordering, storing, transportation, and distribution problems. This model considers the differences between long-term and short-term storage facilities and the quality of wheat. Moreover, the proposed model addresses the uncertainties associated with the quantity of domestic supply and demand through a stochastic scenario-based programming approach. Applicability of this model is investigated using real data from the wheat supply chain of Iran. Results show that seven new long-term storage facilities should be opened, which decreases total costs by 3.45 percent.

Community detection has gained much attention during the past few decades. So many algorithms have been developed to tackle this problem. In previous related works the weight of the edges and directionality were not considered at the same time in the models. Considering weights and directionality makes the models more realistic and prevents the loss of information in the network. In this article, we propose an overlapping community detection algorithm for networks with weighted and directed edges. We used the concept of information flows among the vertices i.e. the more flows exist in a community, the stronger the community. We implemented the concept of flow using weighted closed flows starting from a given node and ending to the same node. By using the mentioned assumption we developed a new modularity measure called weighted flow modularity (WFM) based on M function modularity. In addition, we developed an overlapping score criteria which considers overlap in vertices and edges at the same time and is much faster in the terms of run time. We compared the community detection results in terms of accuracy and running time with Order statistics local optimization method (OSLOM) on 74 LFR benchmark networks using normalized mutual information score. We also implemented the community detection process using LCFE on real world datasets and evaluated the community detection results using EQ measure. The experimental analysis results show that the LCFE is more accurate in most cases and is competitive in other cases with OSLOM.

This paper deals with retrial queues of the |MQ/M/c/∞|- type in which the rate of input flow depends on the number of sources of repeated calls and each call has only one retrial attempt. That is, if a call fails to enter the server facility at the retrial attempt, then it leaves the system without service. The existence conditions of stationary regime and the vector-matrix of the stationary probabilities of the service process are represented. This representation uses an approximation of the initial model by means of the truncated one and the directs passage to the limit. For these systems a threshold strategy for the rate of input flow is used. The multi-criterion optimization problem for finding optimal strategy of control is considered. The quality functionals of the optimization problem are represented through the stationary probabilities.

The maintenance of a sustainable mechanism to curb the rate of overfishing in similar water zones is one of the major challenges facing artisan fisheries in small island regions. Several factors instigate the decision by local fishermen to potentially choose a location to explore. Obviously, the demand to address these triggers, particularly those with negative impact tendencies, has become paramount. This study, therefore, is aimed at mapping out fishing heat spots based on arrival, background of the fishermen, and available species. Subsequently, an evaluation is conducted to ascertain the criteria influencing the decision on a specific position and also to determine the consequences of their negative impact on marine resource sustainability and coastal community welfare. For these reasons, data from fishermen, sellers and local distributors were collected by using questionnaires, and analyzed to generate useful information on related fishing ground. Furthermore, experts were involved in providing expert assessment for Fuzzy Decision Making Trial and Evaluation Laboratory (DEMATEL). The results showed significant insights and therefore offer support to help regulators preserve marine resources, especially by updating their decision making capacity for increased coastal community welfare. The direct implication of this research also serves as a basis for conducting traditional fisheries, estimated not only to meet economic impact, but also promote sustainable environment.

This study aims at investigating the relationship between the degree of internationalization and firm performance in Cameroon. Based on a panel dataset of 114 firms surveyed by the World Bank from 2009 to 2019, the regression results find evidence that there exists a relationship between internationalization and performance with respect to the W-shape while the model controls the characteristics of the business environment and firm characteristics. This result has confirmed the impact of internationalization on the firm performance going through 4 stages (W-shaped). We draw a number of implications for the study of internationalization in both theory and practice.

Bin packing problem is a constrained optimization problem with a huge search space due to large combinations. Bin packing problem has a wide range of applications in multiple fields. This paper presents harmony search algorithm with different initialization and adaptive PAR strategies for solving bin packing problem. The proposed Harmony search (HS) variations tests two partial feasible initialization strategies for bin packing problem. The paper presents adaptive PAR strategies for better exploration and exploitation of HS algorithm. The PAR values are tuned in every iteration. Improved initialization strategy, population initialization after premature convergence and adaptive PAR leads to the better exploration of harmony search algorithm for bin packing problem. The performance of variations are tested over 120 benchmark instances with 100 and 200 objects with varying complexities. The results show that improved HS performs better than basic HS with respect to best, mean, convergence rate. The performance of algorithms is tested with varying harmony memory size and harmony memory considering rate. Results show that variation in these two parameter values has less effect on performance of improved versions.

One of the most important solutions for dimensionality reduction in data preprocessing, and improving classification performance is gene selection in microarray data since they usually have several thousand genes with very few samples. Because of these characteristics, the complexity of classification models increases and their efficiency decreases. The gene selection problem inherently pursues two goals: reducing the number of genes and increasing the classification efficiency. Therefore, this paper presents a novel hybrid filter-wrapper solution based on the Fisher-score method and Multi-Objective Forest Optimization Algorithm (MOFOA). In the proposed method, as a preprocessing step, the Fisher-score method selects 500 discriminative genes by removing redundant/irrelevant genes. Then, MOFOA searches to find the subset of optimal genes using concepts such as repository, crowding-distance, and binary tournament selection. Moreover, the proposed method solves the gene selection problem and, at the same time, optimizes the kernel parameters in the SVM classification model. Six microarray datasets were used to evaluate the performance of the proposed method. Afterward, a comparison was made between its results and those of the four multi-objective hybrid methods presented in the literature in terms of classification performance, the number of selected genes, running time, and hypervolume criteria. According to the results, in addition to selecting fewer genes, the proposed solution has achieved greater classification accuracy in most cases and has been able to obtain a performance similar to or better than that of other multi-objective gene selection approaches.

This paper considered a case of supplier selection problem in a glove manufacturer located at Yogyakarta, Indonesia that uses genuine sheep leather as the raw material. The problem is solved using both Analytical Hierarchy Process (AHP) and Fuzzy AHP, in which three versions of Fuzzy AHP are applied i.e. Extent Analysis proposed by Chang (1996) [Chang, D. Y. (1996). Applications of the extent analysis method on fuzzy AHP. European Journal of Operational Research, 95(3), 649-655.], Extent Analysis proposed by Wang (2008) [Wang, Y. M., Luo, Y., & Hua, Z. (2008). On the extent analysis method for fuzzy AHP and its applications. European Journal of Operational Research,186(2), 735-747.], and the modified Fuzzy LLSM proposed by Wang (2006) [Wang, Y. M., Elhag, T. M., & Hua, Z. (2006). A modified fuzzy logarithmic least squares method for fuzzy analytic hierarchy process. Fuzzy Sets and Systems, 157(23), 3055-3071.]. Moreover, the research is conducted by incorporated four expert respondents, who have more than 12 years of experience in the problem. It is found that the top four priorities obtained from AHP are similar with those from Fuzzy AHP with Extent Analysis proposed by Chang (1996) and Fuzzy AHP with the modified Fuzzy LLSM proposed by Wang (2006). This priority list of supplier can be used by the manufacturer to select the raw material supplier.