• IE interfaces
• /
• v.25 no.4
• /
• pp.458-471
• /
• 2012

In this study, we investigate the cooperative relationships between researchers who have co-authorship in the logistics-related journals in Korea by using social network analysis (SNA). We analyzed the co-authorship data of 781 articles published from 2005 to 2011 in four journals of 'Logistics Study', 'Journal of Korean Society of SCM', 'Korea Logistics Review' and 'Journal of Shipping and Logistics.' We examined the trend of cooperative research in the field of logistics with basic data of the co-authorship network. Then, we analyzed structural properties of the network and the sub-networks of research groups having co-authorship. We could verify the authors who play important roles within the network by using SNA indicators. In addition, we constructed the keyword networks based on the keyword data of all articles by research groups in order to understand the research topics of each group, and thereby we could draw several implications on the cooperative researches in the field of logistics.

• Journal of Korean Institute of Industrial Engineers
• /
• v.37 no.4
• /
• pp.311-322
• /
• 2011

The core of this research studies the strategic alliance of airlines, container shipping liners, and port operators that have shown successful results through the recent differentiated strategic Alliance Network, although a difference of scale exists between these firms and the small and mid-sized International Logistics firms, but because of the worldwide traditional Alliance Network of International Logistics firms, HTFN's(High Tech Forwarder Network) half hearted attitude and the small scale alliance of the small and mid-sized International Logistics firms organized in 1998 cannot breakthrough the present strenuous situation. And these results, creating an attempt to save our country's International Logistics Industry which have fallen into depression, suggests an awakening of a new strategy based on specialized nationals innovative IT-which does not exist in the world market-by categorizing our country's small and mid-sized International Logistics firms which are active worldwide.

• Journal of Intelligence and Information Systems
• /
• v.9 no.2
• /
• pp.1-18
• /
• 2003

The automatic recognition of transport containers using image processing is very hard because of the irregular size and position of identifiers, diverse colors of background and identifiers, and the impaired shapes of identifiers caused by container damages and the bent surface of container, etc. We proposed and evaluated the novel recognition algorithm of container identifiers that overcomes effectively the hardness and recognizes identifiers from container images captured in the various environments. The proposed algorithm, first, extracts the area including only all identifiers from container images by using CANNY masking and bi-directional histogram method. The extracted identifier area is binarized by the fuzzy binarization method newly proposed in this paper and by applying contour tracking method to the binarized area, container identifiers which are targets of recognition are extracted. We proposed and applied the ART2-based RBF network for recognition of container identifiers. The results of experiment for performance evaluation on the real container images showed that the proposed algorithm has more improved performance in the extraction and recognition of container identifiers than the previous algorithms.

• Asian review of World Histories
• /
• v.4 no.2
• /
• pp.191-205
• /
• 2016

The Periplus of the Erythraean Sea is a Roman period guide to trade and navigation in the Indian Ocean. Justly famous for offering a contemporary and descriptive account of early Indian Ocean trade, the work has been subject to and a point of departure for numerous studies. Its extensive influence on scholarship is, however, also problematic, as it reflects the limited information and cultural and personal bias of its unknown author. Arguably this might have led scholars to overemphasise so-called western or Roman participation in early Indian Ocean trade. Network analysis allows us to map, visualize and measure interconnectedness in the Periplus Maris Erythraei. Many of these connections are not explicitly mentioned in the text, but by connecting not only places with places, but also products with places that export and import them, we get a partly different impression of Indian Ocean trade from that conventionally gathered from the Periplus. It allows us to ask questions about the relationship between coastal cabotage and transoceanic shipping, to identify regional trading circuits, and unexpected centres of long-distance exchange.

• Industrial Engineering and Management Systems
• /
• v.8 no.1
• /
• pp.14-21
• /
• 2009

We formulate a mathematical model of remanufacturing system as multi-stage reverse Logistics Network Problem (mrLNP) with minimizing the total costs for reverse logistics shipping cost and inventory holding cost at disassembly centers and processing centers over finite planning horizons. For solving this problem, in the 1st and the 2nd stages, we propose a Genetic Algorithm (GA) with priority-based encoding method combined with a new crossover operator called as Weight Mapping Crossover (WMX). A heuristic approach is applied in the 3rd stage where parts are transported from some processing centers to one manufacturer. Computer simulations show the effectiveness and efficiency of our approach. In numerical experiments, the results of the proposed method are better than pnGA (Prufer number-based GA).

• Journal of Navigation and Port Research
• /
• v.43 no.5
• /
• pp.273-280
• /
• 2019

This study developed an optimization model, defined as the IPS (Itinerary for Passenger Satisfaction), for a cruise ship to identify an itinerary that maximizes passenger satisfaction. A 0-1 integer programming model was developed to provide an optimal sequence of ports of call, assigning a destination to each day of the cruise. The concepts of the destination access network and the neighborhood of a destination were designed and manipulated to organize the complex network of destinations so that each next destination is selected within a practical overnight sail. The developed model can also be viewed as a reduced variant of the traveling salesperson problem with less constraints. A set of example tests shows that practical scenarios of the IPS with moderate cruise duration can be easily solved with light computation loads. Considering cruise ship passengers usually make their decisions not relying on only one destination but on an itinerary in its entirety, the purpose of this study was to identify itinerary alternatives to attract potential cruise passengers for attaining maximum occupancy level.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.29 no.3
• /
• pp.163-174
• /
• 2023

Though box compression strength (BCS) is commonly used as a performance criterion for shipping containers, estimating BCS remains a challenge. In this study, artificial neural networks (ANN) are implemented as a new tool, with a focus on building up ANN architectures for BCS estimation. An Artificial Neural Network (ANN) model can be constructed by adjusting four modeling factors: hidden neuron numbers, epochs, number of modeling cycles, and number of data points. The four factors interact with each other to influence model accuracy and can be optimized by minimizing model's Mean Squared Error (MSE). Using both data from the literature and "synthetic" data based on the McKee equation, we find that model estimation accuracy remains limited due to the uncertainty in both the input parameters and the ANN process itself. The population size to build an ANN model has been identified based on different data sets. This study provides a methodology guide for future research exploring the applicability of ANN to address problems and answer questions in the corrugated industry.

• Journal of Navigation and Port Research
• /
• v.44 no.3
• /
• pp.187-194
• /
• 2020

It is very important to forecast freight volume accurately to establish major port policies and future operation plans. Thus, related studies are being conducted because of this importance. In this paper, stepwise regression analysis and artificial neural network model were analyzed to compare the predictive power of each model on Gwangyang Port, the largest domestic port for coal and iron ore transportation. Data of a total of 121 months J anuary 2009-J anuary 2019 were used. Factors affecting coal and iron ore trade volume were selected and classified into supply-related factors and market/economy-related factors. In the stepwise regression analysis, the tonnage of ships entering the port, coal price, and dollar exchange rate were selected as the final variables in case of the Gwangyang Port coal volume forecasting model. In the iron ore volume forecasting model, the tonnage of ships entering the port and the price of iron ore were selected as the final variables. In the analysis using the artificial neural network model, trial-and-error method that various Hyper-parameters affecting the performance of the model were selected to identify the most optimal model used. The analysis results showed that the artificial neural network model had better predictive performance than the stepwise regression analysis. The model which showed the most excellent performance was the Gwangyang Port Coal Volume Forecasting Artificial Neural Network Model. In comparing forecasted values by various predictive models and actually measured values, the artificial neural network model showed closer values to the actual highest point and the lowest point than the stepwise regression analysis.

• Journal of Korea Port Economic Association
• /
• v.29 no.3
• /
• pp.175-207
• /
• 2013

The purpose of this study is to examine the effects of the interdependent partnership between liner shipping companies and port-related service firms on the service quality and transaction performance. The empirical analysis found that sharing information and mutual trust of partnership factor positively affected service quality of the port-related service firms, but the communication had negative effects on it. The interdependence had the interaction effect between the partnership and the service quality. Also, the service quality affected satisfaction of transaction and re-purchasing of the shipping companies. This study shows that the partnership to be formed mutual dependent relationship between shipping companies and the port-related firms improve the service quality of shipping service network and enhance transactional satisfaction of both parties.

• Journal of the Korean Institute of Navigation
• /
• v.23 no.2
• /
• pp.11-22
• /
• 1999

This paper is concerned with the development of a tractable model to assist liner shipping companies in the decision-making of empty container repositioning and leasing. A hybrid methodology is presented which properly accounts for the specific characteristics of empty container management. For this mathematical models are developed based on dynamic network models, covering both land and marine segment. Then a stochastic method is presented to deal with the uncertainty of the future demand and supply. Especially, the concept of opportunity cost has been introduced in order to explain interactions between the variation of the future demand and supply and the stock level at each depot.