• Journal of the Korean Institute of Gas
• /
• v.16 no.2
• /
• pp.52-59
• /
• 2012

The sprinkler system is regarded as the most effective fire extinguishing system. In this study, we proposed a sprinkler layout optimization framework based on fire simulation and mathematical programming. As a case study, the target space in the form of ordinary residence was set up with the size of $5.2m(L){\times}5.4m(W){\times}2.4m(H)$, and we constructed the fire scenario that polyurethane couch was ignited through carelessness. And we simulated and analyzed fire speed, temperature change and heat release rate according to the type and number of sprinklers installed. Through the formulation of installation and damage costs depending on sprinklers, the sprinkler layout showing optimal performance was resulted from mathematical programming.

• Journal of the Korea Society for Simulation
• /
• v.22 no.1
• /
• pp.63-75
• /
• 2013

The School Bus Routing Problem(SBRP) seeks to plan an efficient schedule of a fleet of school buses that must pick up student from various bus stops and deliver them by satisfying various constraints; maximum capacity of the bus, maximum riding time of students, arrival time between a school's time window. By extending the existing SBRP, we consider a case study of SBRP with allowance of mixed-loading and dynamic arrivals reflecting the school bus operation of university in Korea. Our solution procedure is based on constructing the initial solution using sweep algorithm and then improving solution within the framework of the evolutionary approach known as efficient meta-heuristics. By comparing the various scenarios through the constraints relaxation for reflecting the real operational strategies, we assess the merit of our proposed procedure.

• Journal of the Korea Society for Simulation
• /
• v.20 no.4
• /
• pp.41-48
• /
• 2011

The act of writing a unit test is more an act of design than of verification. It is also more an act of documentation than of verification. The act of writing a unit test closes a remarkable number of feedback loops, the least of which is the one pertaining to verification of function. Unit testing is a fundamental practice in Extreme Programming, but most non-trivial code is difficult to test in isolation. Normal unit testing is hard because It is trying to test the code from outside. On the other hand, developing unit tests with Mock Objects leads to stronger tests and to better structure of both domain and test code. In this paper, I first describe how Mock Objects are used for unit testing of federation integration. Then I describe the benefits and costs of Mock Objects when writing unit tests and code. Finally I describe a design of Mock federate for using Mock objects.

• Journal of the Korean Geotechnical Society
• /
• v.28 no.12
• /
• pp.65-76
• /
• 2012

In this study, probabilistic analysis of seepage through a two-layered soil foundation was performed. The hydraulic conductivity of soil shows significant spatial variations in different layers because of stratification; further, it varies on a smaller scale within each individual layer. Therefore, the deterministic seepage analysis method was extended to develop a probabilistic approach that accounts for the uncertainties and spatial variation of the hydraulic conductivity in a layered soil profile. Two-dimensional random fields were generated on the basis of the Karhunen-Lo$\grave{e}$ve expansion in a manner consistent with a specified marginal distribution function and an autocorrelation function for each layer. A Monte Carlo simulation was then used to determine the statistical response based on the random fields. A series of analyses were performed to verify the application potential of the proposed method and to study the effects of uncertainty due to the spatial heterogeneity on the seepage behavior of two-layered soil foundation beneath water retaining structure. The results showed that the probabilistic framework can be used to efficiently consider the various flow patterns caused by the spatial variability of the hydraulic conductivity in seepage assessment for a layered soil foundation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2011.10a
• /
• pp.466-469
• /
• 2011

Recently, a new theoretical and methodological approach for computational science is becoming more and more popular for analyzing and solving scientific problems in various scientific disciplines such as Computational fluid dynamics, Chemistry, Physics, Structural Dynamics, Computational Design and applied research. Computational science is a field of study concerned with constructing mathematical models and quantitative analysis techniques and using large computing resources to solve the problems which are difficult to approach in a physical experimentally. In this paper, we present R&D of EDISON open integration platform that allows anyone like professors, researchers, industrial workers, students etc to upload their advanced research result such as simulation SW to use and share based on the cyber infrastructure of supercomputer and network. EDISON platform, which consists of 3 tiers (EDISON application framework, EDISON middleware, and EDISON infra resources) provides Web portal for education and research in 5 areas (CFD, Chemistry, Physics, Structural Dynamics, Computational Design) and user service.

• Industrial Engineering and Management Systems
• /
• v.9 no.2
• /
• pp.88-96
• /
• 2010

This paper presents a two-phase quantitative framework to aid the decision making process for effective selection of an efficient freight logistics hub from 8 alternatives in Thailand on the North-South economic corridor. Phase 1 employs both multiple regression and Pearson Feature selection to find the important criteria, as defined by logistics hub score, and to reduce number of criteria by eliminating the less important criteria. The result of Pearson Feature selection indicated that only 5 of 15 criteria affected the logistics hub score. Moreover, Genetic Algorithm (GA) was constructed from original 15 criteria data set to find the relationship between logistics criteria and freight logistics hub score. As a result, the statistical tools are provided the same 5 important criteria, affecting logistics hub score from GA, and data mining tool. Phase 2 performs the fuzzy stochastic AHP analysis with the five important criteria. This approach could help to gain insight into how the imprecision in judgment ratios may affect their alternatives toward the best solution and how the best alternative may be identified with certain confidence. The main objective of the paper is to find the best alternative for selecting freight logistics hub under proper criteria. The experimental results show that by using this approach, Chiang Mai province is the best place with the confidence interval 95%.

• Journal of Intelligence and Information Systems
• /
• v.10 no.3
• /
• pp.11-26
• /
• 2004

Software for analyzing documents on the net to detect specific categories of occurrences is in great demand. In the current world where detecting terrorist threats is critical there is a great need for such systems. One of the critical application areas of such software is the automatic detection of a national infrastructure emergency. In this research an agent-based generic architecture for emergency warning systems is proposed and implemented. This system, called the National Infrastructure Emergency Warning System (NIEWS), is designed to analyze given documents, to detect threats, and to report possible threats with the necessary information to the appropriate users autonomously. In addition, a systematic analysis framework to detect emergencies on the subject of defensive information warfare is designated and implemented through a knowledge base. The developed system along with the knowledge base is implemented and successfully deployed to Strategic Crisis Exercise (SCE) at the United State Army War College (USAWC), saving a good amount of money by replacing human SMEs (subject matter experts) in the SCE.

• Journal of Information Technology and Architecture
• /
• v.9 no.3
• /
• pp.275-285
• /
• 2012

DIFs (Data Interchange Formats) are needed to enhance interoperability of physically distributed organizations in SBA (Simulation Based Acquisition) process. DIFs play a role as a template of DPDs (Distributed Product Descriptions) and provide capability to use information directly without data format interchange process by allowing access to DPDs, which include various information and M&S (Modeling & Simulation) resources. This characteristic is essential for interoperability in ICE (Integrated Collaborative Environment) based SBA. This paper proposes a framework for the DIF and outputs from each phase of acquisition process for configuration data related to design and manufacturing in SBA process - Conceptual Data Model, Logical Data Model, Physical Data Model and Physical DIF based on XML. Finally, we propose the DIF model architecture and demonstrate the implementation of DIF example based on it.

• Journal of KIISE:Computing Practices and Letters
• /
• v.16 no.11
• /
• pp.1126-1130
• /
• 2010

Research on intelligent robot is in active progress as the next generation IT education area. Since intelligent robots are closely related to the real human world, they should provide human behaviors or judging ability as their functions. For this reason, research is recently done not only on diverse hardware of robot education but also on service component architecture which includes various functions. In this paper we propose a study on learning to creative solve problems using RDS(Robotics Developer Studio). RDS is a software tool to control or program intelligence robot as a software module. Using service component framework which considers standardization of the integrated development of intelligent robot, we expect to provide 3-dimensional visual simulation environment, and save time and costs in education the environment for the intelligence robot experiment.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2017.05a
• /
• pp.199-199
• /
• 2017

Sustainable wheat production is of paramount importance for attaining/maintaining the food self-sufficiency status of the rapidly growing nation of Pakistan. However, the average wheat yield per unit area has been dwindling in recent years and the climate-induced variations in rainfall patterns and temperature regimes, during the wheat growth period, are believed to be the reason behind this decline. Crop growth simulation models are powerful tools capable of playing pivotal role in evaluating the climate change impacts on crop yield or productivity. This study was aimed to predict the plausible variations in the wheat yield for future climatic trends so that possible mitigation strategies could be explored. For this purpose, Aquacrop model v. 4.0 was employed to simulate the wheat yield under present and future climatology of the largest agricultural province of Punjab in Pakistan. The data related to crop phenology, management and yield were collected from the experimental plots to calibrate and validate the model. The future climate projections were statistically downscaled from five general circulation models (GCMs) and compared with the base line climate from 1980 to 2010. The model was fed with the projected climate to simulate the wheat yield based on the RCP (representative concentration pathways) 4.5 and 8.5. Under the worst, most likely future scenario of temperature rise and rainfall reduction, the crop yield decreased and water footprint, especially blue, increased, owing to the elevated irrigation demands due to accelerated evapotranspiration rates. The modeling results provided in this study are expected to provide a basic framework for devising policy responses to minimize the climate change impacts on wheat production in the area.