• Proceedings of the Korea Society of Design Studies Conference
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• 2001.10a
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• pp.18.2-18
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• 2001

• JOURNAL OF ELECTRICAL WORLD
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• no.2 s.110
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• pp.14-17
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• 1986

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.3
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• pp.141-150
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• 2013

Simulation is an important technique to test and verify routing protocol correctness. However, simulation does not guarantee that the protocol works expectedly on a real world environment because it needs to rely on assumptions and simplified properties such as radio characteristics and effects of geographical constraints that may not reflect the real world networking environments. Therefore, a real world experiments are necessary to gain a practical insight into the actual performance of ad hoc networks. In this paper, we build a test-bed to evaluate multi-hop ad hoc networks for high speed video streaming inside a building using AODV-UU routing protocol. Our observation indicates that the considered ad hoc network can provide a sufficient performance for a low rate streaming data in terms of throughput, PDR (Packet delivery ratio) and the average delay.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.4
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• pp.60-67
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• 2012

Most of a driving cycle is used to measure fuel consumption (FC) and emissions for a specified vehicle. A driving cycle was reflected geography and traffic characteristics for each country, also, driving pattern is affected these parameters such as vehicle dynamics, FC and emissions. Therefore, this study is an attempt to develop a driving cycle for military operational area. The proposed methodology the driving cycle using micro-trips extracted from real-world data. The methodology is that the driving cycle is constructed considering important parameters to be affected FC. Therefore, this approach is expected to be a better representation of heterogeneous traffic behavior. The driving cycle for the military operational area is constructed using the proposed methodology and is compared with real-world driving data. The running time and total distance of the final cycle is 1461 s, 13.10 km. The average velocity is 32.25 km/h and average grade is 0.43%. The Fuel economy in the final cycle is 5.93 km/l, as opposed to 6.10 km/l for real-world driving. There were about 3% differences in driving pattern between the final driving cycle and real-world driving.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.4
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• pp.1824-1845
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• 2016

The GMM is a conventional approach which has been recently applied in many face recognition studies. However, the question about how to deal with illumination changes while ensuring high performance is still a challenge, especially with real-world databases. In this paper, we propose a Visual Observation Confidence (VOC) measure for robust face recognition for illumination changes. Our VOC value is a combined confidence value of three measurements: Flatness Measure (FM), Centrality Measure (CM), and Illumination Normality Measure (IM). While FM measures the discrimination ability of one face, IM represents the degree of illumination impact on that face. In addition, we introduce CM as a centrality measure to help FM to reduce some of the errors from unnecessary areas such as the hair, neck or background. The VOC then accompanies the feature vectors in the EM process to estimate the optimal models by modified-GMM training. In the experiments, we introduce a real-world database, called KoFace, besides applying some public databases such as the Yale and the ORL database. The KoFace database is composed of 106 face subjects under diverse illumination effects including shadows and highlights. The results show that our proposed approach gives a higher Face Recognition Rate (FRR) than the GMM baseline for indoor and outdoor datasets in the real-world KoFace database (94% and 85%, respectively) and in ORL, Yale databases (97% and 100% respectively).

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.4
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• pp.489-493
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• 2020

The technological development of the Fourth Industrial Revolution is accelerating the development of the world and society. Fourth industrial technology is connected to Cyber World to develop national and social infrastructure. The application of the fourth industrial technology can create Cyber-city and Cyber-life systems. In the ICT business industry that connects Cyber with the real world, we need to connect Cyber with real-life work. It is to use AR business cards as one of the ways to connect Cyber business with real business. When an AR business card is recognized as a smartphone, a 3D character appears to introduce the main character of the business card. In addition, AR business cards are reflected in AR for product and service of business operators, enabling promotion of products, services, etc. Using connected wired and wireless 5G communication, real-time e-commerce is also possible. In this paper, AR business card will be produced with Source Coding and AR business card platform will be designed.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.246-249
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• 2005

Satellite ground track display computer program is designed and implemented for the KOMPSAT-2 mission operations. Digitized world map and detailed Korean map is realized with zoom and pan capability. The program supports real-time ground trace and off-line satellite image planning on the world map. Satellite mission timeline is also displayed with the satellite ground track for the visualized mission operations. In this paper, the satellite ground track display is described in the aspect of the functional requirements, design, and implementation.

• Knowledge Management Research
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• v.9 no.1
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• pp.147-161
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• 2008

In the previous KM (Knowledge Management) studies, it has been repeatedly pointed that CoP (Community of Practice) should be used as a platform for boosting up corporate innovative activities. Despite this, it is very rare to find relevant literature in which real-world cases are introduced showing critical success factors, implemented strategies, and objective analysis of results. In this sense, main objective of this paper is very timely- to introduce a real-world CoP case in which POSCO, world-leading steel company, sorted out creative CoP strategies to nurture knowledge-sharing activities to solve various kinds of problems at hand, and maintain appropriate level of knowledge circulation throughout all the working units of company. In a nutshell, POSCO has been successful in any measure in utilizing the creative CoP activities as strategic means to change the paradigm of innovation and extract fruitful outcomes from integrating three important individual activities such as work, learning, and innovation.

• Journal of the Korean Institute of Navigation
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• v.22 no.4
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• pp.15-19
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• 1998

This paper concerns a bulk or semibulk cargo ship scheduling problem with a single loading port. This type of ship scheduling problem is frequently needed in real world for carrying minerals or agricultural produce from a major single production zone to many destinations scattered over a large area of the world. The first optimization model for this problem was introduced by Ronen (1986) as a nonlinear mixed integer program. The model developed in this paper is an improvement of his model in the sense that nonlinearities and numerous unnecessary integer variables have been eliminated. By this improvement we could expect real world instances of moderate sizes to be solved optimal solutions by commercial integer programming software. Similarity between the ship scheduling model and the capacitated facility location model is also discussed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.9
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• pp.3885-3906
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• 2020

Hybrid fuzzing which combines fuzzing and concolic execution, has proved its ability to achieve higher code coverage and therefore find more bugs. However, current hybrid fuzzers usually suffer from inefficiency and poor scalability when applied to complex, real-world program testing. We observed that the performance bottleneck is the inefficient cooperation between the fuzzer and concolic executor and the slow symbolic emulation. In this paper, we propose a novel solution named EPfuzzer to improve hybrid fuzzing. EPfuzzer implements two key ideas: 1) only the hardest-to-reach branch will be prioritized for concolic execution to avoid generating uninteresting inputs; and 2) only input bytes relevant to the target branch to be flipped will be symbolized to reduce the overhead of the symbolic emulation. With these optimizations, EPfuzzer can be efficiently targeted to the hardest-to-reach branch. We evaluated EPfuzzer with three sets of programs: five real-world applications and two popular benchmarks (LAVA-M and the Google Fuzzer Test Suite). The evaluation results showed that EPfuzzer was much more efficient and scalable than the state-of-the-art concolic execution engine (QSYM). EPfuzzer was able to find more bugs and achieve better code coverage. In addition, we discovered seven previously unknown security bugs in five real-world programs and reported them to the vendors.