• Fire Science and Engineering
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• v.25 no.3
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• pp.51-56
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• 2011

The full-scale experiments are carried out to investigate the fire suppression characteristics of water-based fire fighting systems in a road tunnel. Applied systems are the low-pressure water spray system at 3.5 bar and the high-pressure water mist system at 60 bar. The water flow rate of the high-pressure system is one sixth only of the water spray system. A passenger car and a heptane fuel pan with area of $1.4m^2$ are used as fire sources. A blower system is installed at the tunnel exit to realize the longitudinal ventilation conditions (0.9~3.8 m/s) in the tunnel. Temperatures from the fire source to the down-stream direction are measured by K-type thermocouple trees. The experimental results show that the cooling effect of the high pressure water mist system in the test conditions were equivalent to that of the low pressure water spray system for B-class fire.

• Korean Journal of Social Welfare
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• v.65 no.3
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• pp.183-206
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• 2013

Using Korean Labor and Income Panel Study (wave 1~11) database, this study analyzed the poverty duration of the poor as a whole and by households' characteristics. For this purpose, I first estimated poverty exit rates and reentry rates applying discrete-time hazard model to the sample, and then calculated poverty duration combining these two probability rates. The results show that about a half of poor households are transitory (short-term) poor with 1~2 years of poverty duration. A quarter is chronic (long-term) poor lasting for 5 or more years of poverty duration. The remained quarter can be categorized as the recurrent or mid-term poor. The socioeconomic characteristics of households greatly affect poverty duration. Long-term poverty is prevalent among female-head households, elderly households, single households, or households headed by a person with a lower level of education. If households' heads do not work, or work as temporary or daily-employed workers, the poverty duration tends to be longer. The findings suggest that the poor consist of various social classes with different characteristics. Efficient anti-poverty policy should be based on thoroughly identifying the specific characteristics and needs of each class.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.4 no.2 s.7
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• pp.33-43
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• 2005

In autumn 2000, the Korea Ministry of Construction and Transportation (MOCT) announced that Daejeon metropolitan city, Jeonju and Jeju were chosen to showcase deployment of Intelligent Transportation Systems(ITS). The program called the Advanced Transportation Systems Model Deployment Initiatives makes a significant step in Intelligent Transportation Infrastructure (In) in Korea. The Initiative is poised to increase the performance and efficiency of the area's roadway and transportation systems to meet growth demand. Three citie's $\$$50 million Model Deployment Initiative project is poised to increase the performance and efficiency of the area's roadway and transportation systems to meet growth demand. The effort particularly focused on the traveler information systems that should raise the level of ITS awareness in Korea. In this paper, project management, funding, private investment, procedures and detailed review of ITS Model Deployment Initiatives are discussed.

• Journal of the Korea Convergence Society
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• v.9 no.10
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• pp.209-215
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• 2018

The level of cultural enjoyment in Korea has improved every year, but the culture that the general public possesses artworks has not developed so much. Most artwork trading systems, from traditional ones to the latest blockchain-based ones, are designed for expensive artwork trading and are hardly accessible to the general public. In this paper, we propose a blockchain-based artwork trading system that can improve the culture of the general public's art collection and contribute to the popularization of fine art. The proposed system consists of three interacted blockchains for identification, artwork registration and smart contract. The proposed system utilizes the advantages of the blockchain system for users to provide trust to each other, and introduces the concept of art notebook for artists to build trust in their own artwork. Since the proposed system builds a trust system through participants rather than experts or external organizations, it can reduce the cost of trading and deal with artworks that can be owned by the general public.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.1
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• pp.83-91
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• 2000

This paper presents a new technique to reduce a large interconnect circuit with tens of thousands of elements into the one that is small enough to be analyzed by circuit simulators such as SPICE. This technique takes a fundamentally different approach form the conventional methods based on the interconnect circuit structure analysis and several rules based on the Elmore time constant. The time moments are computed form the circuit consisting of the interconnect circuit and the CMOS gate driver model computed by the AWE technique. Then, the equivalent RC circuit is synthesized from those moments. The characteristics of the driving CMOS gate can be reflected with the high degree of accuracy and the size of the compressed circuit is determined by the number of output nodes regardless of the size of the original interconnect circuits. This technique has been implemented in C language, applied to several interconnect circuits driven by a 0.5${\mu}m$ CMOS gate and the equivalent RC circuits with more than 99% reduction ratio and accuracy with 1 ~ 10% error in therms of propagation delays were obtained.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.1
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• pp.72-79
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• 2011

The importance of parallel programming seriously emerges ever since the modern microprocessor architecture has been shifted to the multi-core system. Transactional Memory has been proposed to address synchronization which is usually implemented by using locks. However, the lock based synchronization method reduces the parallelism and has the possibility of causing deadlock. In this paper, we propose an efficient method to utilize transactional memory for the situation which has high contention. The proposed idea is based on the theoretical analysis and it is verified with simulation results. The simulation environment has been implemented using HTM(Hardware Transactional Memory) systems. We also propose a model of the dining philosopher problem to discuss the efficient resource management using the transactional memory technique.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.9
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• pp.60-67
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• 2013

Test cost reduction is necessary to test a complex System-on-a-Chip(SoC) which adopts various Intellectual Properties (IP). In this paper, test architecture with low pin count which is able to IP-based SoC test, using IEEE Std. 1149.7 and IEEE Std. 1500, is proposed. IEEE Std. 1500 provides independent access mechanism for each IP in IP-based SoC test. In this paper, just two test pins are required by composing that these independent access mechanism can be controlled by IEEE Std. 1149.7. The number of Chips which are tested at the same time is increased by reducing required test pin count at wafer and package level test, and consequently the overall manufacturing test cost will be reduced significantly.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.7
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• pp.720-728
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• 2011

In this paper, development of the monopulse secondary surveillance radar antenna which can be used for IFF system is presented. This antenna that is passive linear array is comprised of the row-feeder and several array-elements. The row-feeder provides sum, different and SLS(Sidelobe Supression) channels which are optimized the distribution of the power and phase ratio. The azimuthe sidelobe level of the sum channel beam pattern is -20 dBc or less. The SLS channel covers the sidelobe of the sum-chanel in the whole azimuth angle range. And the difference channel is used to perform the mono-pulse function, improves the detection accuracy in the azimuth direction. Meanwhile, the arrayelement makes shaped beam in the elevation angle, in order to eliminate the clutter and multipath effects from the ground. Performance of the antenna developed is verified by the measurement of S-parameters and far-field beam pattern, and satisfies all of the development specifications well.

• Journal of the Korean Geotechnical Society
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• v.21 no.2
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• pp.67-84
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• 2005

This research was conducted to evaluate the effectiveness of reinforcement for nearly saturated soft clay compaction. The effectiveness was investigated by roller compaction test using nearly saturated clay specimens. The nearly saturated condition was obtained by submerging clay in the water for 12 hours. High water content specimens were compacted in plane strain condition by a steel roller. A specimen was compacted by four 5 cm horizontal layers. Specimens were prepared fur both reinforced and unreinforced cases to evaluate the effectiveness of reinforcement. Used reinforcement is a composite consisted of both woven and non-woven geotextile. The composite usually provides drainage and tensile reinforcement to hi인 water-contented clay so that it increases bearing capacity. Therefore, large compaction load can be applied to reinforced clay and it achieves higher density effectively. The reinforcement also increases compaction efficiency because it reduces the ratio between shear and vertical forces during compaction process. The maximum vertical stress on the base of specimen usually decreased with higher compaction thickness. The reinforcement increases soil stiffness under the compaction roller and it initiates stress concentration. As a result, it maintains higher vertical stress level on the base of specimen that provides better compaction characteristics. Based on test results, it can be concluded that the reinforcement is essential to achieve effective compaction on soft clay.

• 한국HCI학회:학술대회논문집
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• 2006.02b
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• pp.770-779
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• 2006

한국 사회에서 사이버 공간, 특히 온라인 게임 세계가 사용자들에게 단순한 게임이나 가상 공간이 아닌 다양한 활동을 통해 현실과는 다른 방식의 또 다른 인생을 살아가는 새로운 생활공간으로 기능하고 있다. 본 연구에서는 온라인 게임 공간에서의 라이프스타일 유형을 확인하고, 리니지 2 와 메이플스 토리라는 두 가지 MMORPG 게임에서 이 유형이 어떻게 나타나는지를 확인하였다. 온라인 게임 '리니지'에서 구분된 온라인 라이프스타일은 '싱글 플레이어', '공동체지향 게이머', '탈사회적 게이머'였다.'리니지 2'를 대상으로 연구 결과, 온라인 게임 공간에서의 공동체 활동은 크게 공동목표, 집단유대감, 집단존중감, 집단영향력의 요인들로 구성되어있는 것으로 확인되었다. 온라인게임 사용자들은 온라인 게임에서 현실감, 조작용이성, 성취감, 친밀감, 소속감, 일탈적 행위를 통한 카타르시스를 통해 재미를 느끼는 것으로 확인되었다. 하지만, 이런 성향은 메이플스토리라는 저 연령층의 게임에서는 비교적 다르게 나타났다. 혈맹 또는 길드의 가입 비율은 비슷한 수준이었지만, 활동방식은 라이프스타일에 따라 다르게 나타났다. 게임세계에서의 라이프스타일은 연령이나 게임 사용기간에서는 큰 차이가 없는 것으로 나타났다. 그러나 공동체 활동과 온라인 게임에서 얻는 재미의 하위 요인들에서는 분명한 차이가 있는 것으로 확인되었다. 공동체 활동과 재미를 느끼는 측면에서의 차이로 인해 결국 온라인 게임에 몰입하는 정도도 차이가 있는 것으로 나타났다. 본 연구는 사이버 공간에서의 사람들의 심리적, 행동적 특성, 특히 온라인 게임에서의 사람들의 공동체 활동과 재미의 요소들을 탐색하였다는 측면에서 의의가 있다. 사람들이 온라인 게임 세계에 몰입하도록 만드는 요인들을 구체적으로 확인할 수 있었다는 측면에서 향후 사이버 공간을 기획하는 사람들에게 구체적인 시사점을 제시할 것이다.