• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.6
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• pp.32-48
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• 2023

Autonomous driving technology is shaping the future of personalized travel, encouraging personalized travel, and traffic impact could be influenced by individualized travel behavior during the transition of driving entity from human to machine. In order to evaluate traffic impact, it is necessary to estimate the total number of trips based on an understanding of individual travel characteristics. The Activity-based model(ABM), which allows for the reflection of individual travel characteristics, deals with all travel sequences of an individual. Understanding the relationship between travel and travel must be important for assessing traffic impact using ABM. However, the ABM has a limitation in the data hunger model. It is difficult to adjust in the actual demand forecasting. Therefore, we utilized a Tour-based model that can explain the relationship between travels based on household travel survey data instead. After that, vehicle registration and population data were used for correction. The result showed that, compared to the KTDB one, the traffic generation exhibited a 13% increase in total trips and approximately 9% reduction in working trips, valid within an acceptable margin of error. As a result, it can be used as a generation correction method based on Tour, which can reflect individual travel characteristics, prior to building an activity-based model to predict demand due to the introduction of autonomous vehicles in terms of road operation, which is the ultimate goal of this study.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.5
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• pp.688-699
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• 2017

Model-based test, a well-known method of the black box tests, is consisted of the following four steps : model construction using requirement, test case generation from the model, execution of a SUT (software under test) and detection failures. Among models constructed in the first step, state-based models such as UML standard State Machine are commonly used to design event-based embedded systems (e.g., weapon control systems). To generate test cases from state-based models in the next step, coverage-based techniques such as state coverage and transition coverage are used. Round-trip path coverage technique using W-Method, one of coverage-based techniques, is known as more effective method than others. However it has a limitation of low failure observability because the W-Method technique terminates a testing process when arrivals meet states already visited and it is hard to decide the current state is completely same or not with the previous in the case like the GUI environment. In other words, there can exist unrevealed faults. Therefore, this study suggests a Extended W-Method. The Extended W-Method extends the round-trip path to a final state to improve failure observability. In this paper, we compare effectiveness and efficiency with requirement-item-based technique, W-Method and our Extended W-Method. The result shows that our technique can detect five and two more faults respectively and has the performance of 28 % and 42 % higher failure detection probability than the requirement-item-based and W-Method techniques, respectively.

• The Transactions of the Korea Information Processing Society
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• v.7 no.11
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• pp.3490-3499
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• 2000

There are two approaches, HA(Home Agent)-based and FA(Froegn Agent)-based mulicasting in mobile computing environments based on mobile IP. If we consider efficiency of routing and bandwidth the FA-based model is better than the HA-based model. But in the case of a MH(Mobile Host) moves frequently it shows bad connection durability because of join and graph delays. To overcome this and to support effective mobile multicasting we propose an extended FA-based multicast routing. In our model previous FA for wards multicast packets to MH. while new FA processes a jion request from MH. That is in general case our model supports FA-based multicasting for efficiency but it provides unicast-based mulicasting for connection durability when MH moves to new FN(Roreign Network). To evaluate our model, we analyze connecction durability, bandwidth, overheads and routing sosts in many situations and compare with previous works.

• Journal of Distribution Science
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• v.18 no.5
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• pp.89-98
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• 2020

Purpose: The growth of online commerce is now becoming a major threat and a new opportunity for retailers. Existing offline retailers struggle to cope with new online retailers' threats by utilizing offline infrastructure. Besides, online retailers expand their online strengths to offline sales by opening their offline stores. Many retailers are paying close attention to the O2O business and the resulting changes. Thus, this research focuses on the O2O business model and process that retailers can adopt. Research design, data and methodology: Considering the features of products that retailers sell, this paper divides O2O business process with the following criteria: delivery lead-time and delivery area. And This research uses the business model canvas to define the features of O2O commerce business process. This paper also uses nine key elements in the business model canvas for analyzing the structure of O2O commerce business. Results: This paper suggests the delivery model of retailers respond to offline customer orders and summarizes the following results. (1) Considering characteristics such as logistics process, delivery area, and product type, we define the features of O2O business models: wide-area (warehouse) based O2O business model, regional area (store) based O2O business model and time-separated O2O business model. (2) This study checks the availability of the business model through the business cases of O2O business models. (3) This study also analyzes the O2O business model of domestic retail companies by the factors defined in the business model canvas. Conclusions: Retailers can adopt the O2O business process to fit their business requirements and strategy. The online retailers who deal with normal consumer products mainly have the wide-area based O2O business model. The wide-area based O2O business model can be suitable for retailers who manage inventory centrally. The time-separated O2O business model can be a good solution for fresh food retailers to operate the logistics process efficiently. And to shorten the delivery lead-time of fresh foods, the regional area based O2O business model can be fit to the retailer that utilizes its offline logistics or sales infrastructure. It may be much more important for retailers to share the inventory information with other branches and to change the role of offline stores.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.9
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• pp.1898-1904
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• 2009

Recently, real documents such as newspapers as well as blogs include newly coined words such as "Wikipedia". However, most previous information processing technologies cannot deal with these newly coined words because they construct their dictionaries based on materials acquired during system development. In this paper, we propose a model to automatically recognize Korean unknown words excluded from the previously constructed dictionary. The proposed model consists of an unknown noun recognition phase based on full text analysis, an unknown verb recognition phase based on web document frequency, and an unknown noun recognition phase based on web document frequency. The proposed model can recognize accurately the unknown words occurred once and again in a document by the full text analysis. Also, the proposed model can recognize broadly the unknown words occurred once in the document by using web documents. Besides, the proposed model fan recognize both a Korean unknown verb, which syllables can be changed from its base form by inflection, and a Korean unknown noun, which syllables are not changed in any eojeol. Experimental results shows that the proposed model improves precision 1.01% and recall 8.50% as compared with a previous model.

• International Journal of Highway Engineering
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• v.13 no.3
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• pp.111-119
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• 2011

The noise prediction model, KRON-2006, in South Korea has been developed for obtaining the average noise level. The model is based on an outdoor sound propagation method based on ISO9613 and ASJ Model-1998 and supports the analysis of the linear noise source, such as highway, for obtaining Leq. Because of that, the model can't obtain Lmax, Lmin from the time series noise profile based on traffic at every moment. In order to address this problem, the real time noise prediction model based on traffic simulation using GIS model and algorithm is proposed. It can predict the vehicle point noise level based on vehicle type, speed generated from traffic simulation by using headway and obtain Lmax, Lmin as integrating the noise profile generated from it at every moment. An evalution of the noise prediciton model using field measurements finds good agreement between predicted and measured noise levels at 1m, 8m, 15m from curb of the near side lane.

• Journal of Forest and Environmental Science
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• v.28 no.4
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• pp.205-211
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• 2012

Yield tables are a frequently used data base for regional timber resource forecasting. A normal yield table is based on two independent variables, age and site (species constant), and applies to fully stocked (or normal) stands while empirical yield tables are based on average rather than fully stocked stands. Normal and empirical yield tables essentially have many limitations. The limitations of normal and empirical yield tables led to the development of variable density yield tables. Mathematical models for estimating timber yields are usually developed by fitting a suitable equation to observed data. The model is then used to predict yields for conditions resembling those of the original data set. It may be accurate for the specific conditions, but of unproven accuracy or even entirely useless in other circumstances. Thus, these models tend to be specific rather than general and require validation before applying to other areas. Dalbergia sissoo forms a major portion of irrigated plantations in the hot desert of India and is an important timber tree species where stem wood is primarily used as timber. Variable density yield model is not available for this species which is very crucial in long-term planning for managing the plantations on a sustained basis. Thus, the objective of this study was to develop variable density yield model based on the data collected from 30 sample plots of D. sissoo laid out in IGNP area of Rajasthan State (India) and measured annually for 5 years. The best approximating model was selected based on the fit statistics among the models tested in the study. The model develop was evaluated based on quantitative and qualitative statistical criteria which showed that the model is statistically sound in prediction. The model can be safely applied on D. sissooo plantations in the study area or areas having similar conditions.

• Journal of Korean Society of Transportation
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• v.18 no.2
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• pp.73-89
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• 2000

This Paper documents the development of a cycle free based, coordinated dynamic signal timing model for minimizing queue lengths using Genetic A1gorithm. The model was embodied using MAT-LAB, the language of technical computing. A special feature of this model is its ability to manage queue lengths of turning movements at the start of green times. The model produces a cycle-free based signal timing(cycles and green times) for each intersection to minimize queue lengths of turning movements on the cycle basis. Concurrently, appropriate offsets could be accomplished by applying cycle-free based signal timings for respective intersections. The model was applied to an example network which consists of three intersections. The result shows that the model produces superior signal timings to the existing signal timing model in terms of managing queue lengths of turning movements.

• Journal of KIISE:Software and Applications
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• v.36 no.9
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• pp.718-731
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• 2009

Software Maintenance needs to continually improve from corrective maintenance to operational management and service improvement. In this study, we propose a software maintenance maturity model and its evaluation criteria based on 4 maintenance projects of K organization. For the proposal, we derive 13 process areas and 64 evaluation criteria based on some references such as SMMM, ITSMM, ITIL. We evaluate the criteria using 5-point scale, and then establish the maturity model of K organization classified by levels of the maturity model based on the evaluation result. And, to verify and improve the maturity model of K organization, we propose improvements for evaluation criteria. In addition, we apply the maturity model to the 4 projects, evaluate the projects, and propose improvements for the projects based on the evaluation result to identify how the model shows software maintenance improvement.

• Proceedings of the Korea Society for Simulation Conference
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• 2001.10a
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• pp.306-312
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• 2001

In this research, we are trying to develop a framework to evaluate the prevention program for Tsunami disaster based on the Multi-agent simulation model. Tsunami has arisen by the earthquake. It happened after flew minutes or few hours when it occurred. It is clear that Tsunami will come after earthquake and from seashore. If we prevent the damage by Tsunami, we should make people who is in the seashore and lived near the seaside escape from there. Moreover we must forecast the escape activity from Tsunami. Former research of this field, some researches try to forecast the escape activity as macro level. However, people who escape from Tsunami is differ from their physical ability and ability of information processing. It needs a more accuracy model to forecast the escape activity of them. Furthermore they make a decision step by step using the various information. Therefore escape activity from Tsunami will describe using an agent based model which can only treat the information processing of human being. In this paper, we develop the evacuation model from Tsunami disaster using the Multi agent based model. The purpose of this study is to analyze the human action pattern when Tsunami occurred, and to make an accurately assessment for damages by Tsunami. The Fujisawa city government is planning and operating the various prevention program far Tsunami. However nobody assess it, because they do not have any simulation models for Tsunami disaster. If they want to set an effective prevention program for Tsunami, they should have any kinds of simulation model. The results of this study are 1) To develop the Multi agent based evacuees escape activity model. 2) Assess the damage of Tsunami in Fujisawa-City.