• Journal of the Korean Geographical Society
• /
• v.39 no.3
• /
• pp.444-456
• /
• 2004

Recently spatial modeling that combined GIS and Cellular Automata(CA) which are based on dynamic process modeling has been discussed and investigated. However, CA-based spatial modeling in previous research only provides the general modeling framework and environment, but lacks of providing simulation or transition rules for modeling. This study aims to propose a methodology for extracting spatial relation rules using GIS and Knowledge Discovery in Database(KDD) methods. This new methodology has great potentials to improve CA-based spatial modeling and is expected to be applied into several examples including urban growth simulation modeling.

• IE interfaces
• /
• v.18 no.4
• /
• pp.390-401
• /
• 2005

In this paper, we propose an efficient internet-based logistics brokerage concept which can overcome the weakness of the traditional off-line method to intermediate between vehicle owners and shippers for matching empty vehicles and freights. For defining a business model based on the new concept and implementing an information system, it is necessary to analyze the business process for the internet-based logistics brokerage using a modeling methodology. In this paper, we analyze the logistics brokerage process using the UN/CEFACT Modeling Methodology (UMM) being utilized as a standard modeling methodology in the area of electronic commerce. After analyzing the business process, we can expect that the UMM can be used as a useful tool for modeling the business process of electronic commerce in which the description of the collaborative work is very important.

• The Journal of Information Systems
• /
• v.28 no.4
• /
• pp.271-291
• /
• 2019

Purpose The purpose of this study is to propose a methodology to derive positive keywords and negative keywords through deep learning to classify reviews into positive reviews and negative ones, and then refine the results of topic modeling using these keywords. Design/methodology/approach In this study, we extracted topic keywords by performing LDA-based topic modeling. At the same time, we performed attention-based deep learning to identify positive and negative keywords. Finally, we refined the topic keywords using these keywords as filters. Findings We collected and analyzed about 6,000 English reviews of Gyeongbokgung, a representative tourist attraction in Korea, from Tripadvisor, a representative travel site. Experimental results show that the proposed methodology properly identifies positive and negative keywords describing major topics.

• Proceedings of the Korean Society for Rock Mechanics Conference
• /
• 2011.09a
• /
• pp.23-33
• /
• 2011

The key features of an intelligent and dynamic design methodology for rock engineering projects has been introduced and summarized firstly, which include some new functions such as intelligent recognition of mechanical rockmass parameters, strategies to select modeling methods and codes, integrated feedback modeling and information, and technical auditing in rock engineering design process. Then typical examples of applications of the dynamic design methodology in some large slopes, underground powerhouses in China are summarized. The discussions are given for the future of the methodology.

• International Journal of Quality Innovation
• /
• v.6 no.1
• /
• pp.74-97
• /
• 2005

IDEF0 is the IEEE standard for functional enterprise modeling and has been used for business process modeling or process mapping in US and Europe. But it does not reflect the potential benefits of modeling and simulation of the dynamic aspects of an enterprise or a system. On the other hand, simulation tools concentrate mostly on the simulation of material flows and are difficult to include information flows and control flows. Additionally, the simulation models that include elements such as queues, event generators and process nodes is a visual interactive representation for the model builder, but is inconvenient for the domain expert. In an attempt to fill that void, we provide an integration of business process and simulation models in this paper. An enhancement of the IDEF0, called parameterized IDEF0, is proposed and its conversion mechanism to network simulation model is developed. Using this methodology, business process models for alternative systems can be evaluated and compared through simulation on time, cost, and quality metrics. As an application of the proposed methodology, economic evaluation of EDI (Electronic Data Interchange) for time-based BPR (Business Process Redesign) is demonstrated. In addition to BPR, the developed methodology may be further integrated with ABC (Activity Based Costing), TQM (Total Quality Management), and economic evaluation of information systems.

• Korean Journal of Computational Design and Engineering
• /
• v.21 no.2
• /
• pp.204-214
• /
• 2016

Shipbuilding process takes a long time for producing final products, and needs many different resources. Because of these characteristics, it has been studied about shipyard simulation and virtual manufacturing that is able to implement the virtual manufacturing process. However, among the previous researches, it requires considerable time and effort to construct simulation model since the systematic methodology has not been used for simulation modeling. Also, reusability of constructed simulation model was low. Therefore, this research defines the method to construct shipyard simulation system using the process-centric simulation modeling methodology and shipyard simulation framework. This paper also validates the utility of this methodology through applying to construct simulation model for the shipyard master plan validation.

• Journal of Information Technology Services
• /
• v.16 no.3
• /
• pp.113-125
• /
• 2017

Customers have been affected by others' opinions when they make a purchase. Thanks to the development of technologies, people are sharing their experiences such as reviews or ratings through online or social network services, However, although ratings are intuitive information for others, many reviews include only texts without ratings. Also, because of huge amount of reviews, customers and companies can't read all of them so they are hard to evaluate to a product without ratings. Therefore, in this study, we propose a methodology to predict ratings based on reviews for a product. In a methodology, we first estimate the topic-review matrix using the Latent Dirichlet Allocation technic which is widely used in topic modeling. Next, we predict ratings based on the topic-review matrix using the artificial neural network model which is based on the backpropagation algorithm. Through experiments with actual reviews, we find that our methodology can predict ratings based on customers' reviews. And our methodology performs better with reviews which include certain opinions. As a result, our study can be used for customers and companies that want to know exactly a product with ratings. Moreover, we hope that our study leads to the implementation of future studies that combine machine learning and topic modeling.

• Nuclear Engineering and Technology
• /
• v.48 no.5
• /
• pp.1192-1205
• /
• 2016

Field programmable gate array (FPGA)-based systems are thought to be a practical option to replace certain obsolete instrumentation and control systems in nuclear power plants. An FPGA is a type of integrated circuit, which is programmed after being manufactured. FPGAs have some advantages over other electronic technologies, such as analog circuits, microprocessors, and Programmable Logic Controllers (PLCs), for nuclear instrumentation and control, and safety system applications. However, safety-related issues for FPGA-based systems remain to be verified. Owing to this, modeling FPGA-based systems for safety assessment has now become an important point of research. One potential methodology is the dynamic flowgraph methodology (DFM). It has been used for modeling software/hardware interactions in modern control systems. In this paper, FPGA logic was analyzed using DFM. Four aspects of FPGAs are investigated: the "IEEE 1164 standard," registers (D flip-flops), configurable logic blocks, and an FPGA-based signal compensator. The ModelSim simulations confirmed that DFM was able to accurately model those four FPGA properties, proving that DFM has the potential to be used in the modeling of FPGA-based systems. Furthermore, advantages of DFM over traditional reliability analysis methods and FPGA simulators are presented, along with a discussion of potential issues with using DFM for FPGA-based system modeling.

• Journal of KIISE:Computing Practices and Letters
• /
• v.16 no.11
• /
• pp.1041-1045
• /
• 2010

Clusters can provide scalable and flexible architectures for parallel computing servers and data centers. Their performance prediction has been a very challenging issue. Existing performance measurement methodologies are able to measure the performance of servers already constructed. Thus they cannot provide a way to predict the overall system performance in advance when designing the system at the initial phase or adding more nodes for more capacity. Therefore, the performance modeling and prediction methodology for large-scale clusters is highly required. In this paper, we suggest a methodology to predict the performance of large-scale clusters, which consists of measurement, modeling and prediction steps. We apply the methodology to a real cluster server and show its usefulness.

• Journal of the Korea Society for Simulation
• /
• v.8 no.4
• /
• pp.109-124
• /
• 1999

The major objective of this research is to design and build the variable structure DEVS modeling & simulation framework. To do this, we have proposed the direct message passing mechanism between the model and its simulator to deal with the structural demand from the model during the simulation. In this approach, four types of basic messages are introduced for the vertical(creation/deletion of the child) and horizontal(creation/deletion of the brother) structural changes. Proposed methodology has been successfully applied to the multi-processor system and the forest fire information system.