• Journal of Korea Port Economic Association
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• v.22 no.3
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• pp.189-207
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• 2006

As the development of Northeast Asian logistics hub becomes one of the national agenda for further development, the sea&Air transport around the Yellow Sea regions has drawn attention of many scholars and government officials. The Sea&air transport is a mode of transportation combining the advantage of high-speed in air transport with the advantage of low-price in sea transport. Hence the sea&air aims at a niche market between air and sea. This paper reviews the possibility of development of the sea&air transport in the aspects of competitiveness over other modes, future demand condition, and the change of the technology and transport environment. The result is that the sea&air is competitive in the aspect of time as well as cost, and sustainable in the aspect of future demand condition. But, it is not stable in the aspect of the conditions of technology or transport demand. Especially, the progress of air transport technology which is aiming at the door-to-door transport among mid- and small- cities, and the rapidly increasing strategic alliances of international airlines with Chinese airlines for the market of China will undermine the stability of the sea&air transport seriously As alternatives, this paper proposes the 3-stage development strategy of sea&air transport. First, at the stage of transshipement, the development of high speed vessels to reduce the time crossing the Yellow Sea and the proactive marketing strategy to induce Chinese-owned products should be emphasized. Second, the value added logistics activity which will secure the demand of the sea&air transport should be developed. Third, demand creation by developing the SCM hub in Incheon is final goal for the logistics hub strategy as well as the sea&air transport.

• Journal of Broadcast Engineering
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• v.20 no.2
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• pp.283-299
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• 2015

In this paper, we propose new broadcasting services that combine MMT (MPEG Media Transport) standard with MPEG-DASH (Dynamic Adaptive Streaming over HTTP) standard. MMT is a next-generation multimedia transport standard that is IP-friendly and provides functionalities appropriate for hybrid broadcasting that uses broadcast physical channels and the Internet simultaneously. MPEG-DASH enables media streaming services that can be dynamically adaptive both to the network traffic conditions of wired and/or wireless Internet and the receiving entity environment. We explain the scenarios of the proposed broadcasting services and demonstrate that various hybrid broadcasting services can be easily realized through the combined usage of MMT and MPEG-DASH. By making the test bitstreams containing contents for the new services and developing the receiver back-end software that performs the function of the receiving entity for the new services on personal computers, we verified that the proposed scenarios can be realized.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.12
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• pp.4795-4802
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• 2010

In order to solve the traffic problem in jeju, we must reduce demand for car travel. In addition, demand for passenger travel by public transport policy is needed for conversion. And to improve the quality of public transport services are desperately needed. The purpose of this study, personal characteristics of the trip traveler and the relationship between transportation choice, and personal effectiveness as a factor in travel costs and travel time on the impact of transportation choices will investigate. Restructure its public transportation routes, when to switch to buses to car traffic on the data as a basis for the factors that may be. In addition to improving the quality of public transport services is expected to be able to contribute. To study the performance of the May 2010 survey was conducted. And multinominal logit model were conducted. According to the analysis, People who own homes and families with more than 5 people are likely to use cars. If a prolonged travel time is likely to use buses. However, increasing the cost of travel increases the likelihood that the car is available.

• Journal of Korea Port Economic Association
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• v.28 no.4
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• pp.1-37
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• 2012

The purpose of this paper is to estimate the social costs induced by various transport modes such as truck, rail and sea vessel. For this purpose, we introduce the damage function of each transport modes, and estimate social costs for 10 items using Meta Analysis. As a results, this study can find that shipping is the most efficient transport mode because it gives the lowest social costs among them. This study also find that the iso-cost transport distance that gives the equal social costs between the transport modes. Our methodology can be thought somewhat inferior to the Contingent Valuation Methods, however the advantage of this methodology is that we can decomposite the total social costs into item by item and can apply it to other researches.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.2343-2358
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• 2008

The modal spilt for road has been increased, but, for railroad it has been decreased from 17.2%(1990) to 6.3%(2006). It is important to study on improving competition for railroad transportation so that freight transport industry for railroad which is getting to decrease in Korea will be increased. The objective of this study is to analyze the competitiveness of railroad transport compared with road by providing a high-speed railway. The indicators representing the competitiveness of railroad transport are determined. The main influenced factors for mode choice include transport cost, transport time, level of service. Precisely, three commodities type, container, cement, steel, are analyzed.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.6
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• pp.64-72
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• 2009

In this paper, a high efficiency 2.45 GHz rectenna with a microstrip patch antenna and a dual-mode band-pass filter in which the 2nd and 3rd harmonics are suppressed, is presented. From the experimental results, the 2.45GHz rectenna using 3rd harmonic suppressed dual-mode BPF shows the conversion efficiency of 41.6% with incident power density of 0.3 mW/cm2 and the received power of 1.66 mW. This result shows high conversion efficiency because the received power of this rectenna is lower than other rectennas to be compared with. This rectenna can be applied to the WPT (Wireless Power Transmission) field for energy harvesting. Also, it is expected to be used to provide the stand-by power for the low power devices for USN, and wireless power transfer in sensor application of MEMS devices.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.2
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• pp.77-83
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• 2011

In this paper, we present the design procedure of the synchronizer and the demodulator of a 13.56MHz RFID PJM tag, which was standardized in ISO 18000-3 mode 3. We optimize the algorithms in order to minimize the number of registers and implement them based on international standard. The designed module is simulated by Modelsim and FPGA. The synchronizer is composed of 3 correlators that is implemented by 1,024(16bit ${\times}$ 64cycle) registers. The demodulator is composed of 2 correlators that is implemented by 128(2bit ${\times}$ 64cycle) registers. The simulation performed with the demodulator integrated with the synchronizer shows that it works at about 87% success rate with the test data of SNR -2dB and 100% with those of SNR 4dB.

• Journal of Environmental Science International
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• v.22 no.6
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• pp.651-666
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• 2013

This study introduces a novel approach to the differentiation of two phenomena, Asian Dust and haze, which are extremely difficult to distinguish based solely on comparisons of PM10 concentration, through use of the Optical Particle Counter (OPC), which simultaneously generates PM10, PM2.5 and PM1.0 concentration. In the case of Asian Dust, PM10 concentration rose to the exclusion of PM2.5 and PM1.0 concentration. The relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration were below 40%, which is consistent with the conclusion that Asian Dust, as a prime example of the coarse-particle phenomenon, only impacts PM10 concentration, not PM2.5 and PM1.0 concentration. In contrast, PM10, PM2.5 and PM1.0 concentration simultaneously increased with haze. The relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration were generally above 70%. In this case, PM1.0 concentration varies because a haze event consists of secondary aerosol in the fine-mode, and the relative ratios of PM10 and PM2.5 concentration remain intact as these values already subsume PM1.0 concentration. The sequential shift of the peaks in PM10, PM2.5 and PM1.0 concentrations also serve to individually track the transport of coarse-mode versus fine-mode aerosols. The distinction in the relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration in an Asian Dust versus a haze event, when collected on a national or global scale using OPC monitoring networks, provides realistic information on outbreaks and transport of Asian Dust and haze.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.5
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• pp.72-79
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• 2010

In this paper, we describe the design and implementation of a high efficiency Doherty power amplifier using gallium nitride (GaN) high-electron mobility transistor (HEMT). The carrier and peaking amplifiers of the proposed Doherty power amplifier consist of the switching-mode Class-E power amplifiers. The test conditions are a duty of 10% and a pulse width of $100\;{\mu}s$ and pulse repetition frequency (PRF) of 1 kHz for a S-band radar application. A RF performance peak PAE of 64% with drain efficiency of 80.6%, at 6 dB output back-off point from saturated output power of 45.5 dBm, was obtained at 2.85 GHz.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.13 no.2
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• pp.68-79
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• 2014

This paper analyzes the characteristics of trip chaining activities of elderly and explores temporal and spatial distribution. The research also estimates ordered probit model and binary logistic model to investigate various factors affecting trip chaining and mode choice patterns. We utilized household survey data for elderly conducted in 2006 and 2010 in Seoul metropolitan area. Research results indicate that trip chaining showed an increasing trend and simple trip chaining counts for more than 85%. GIS mapping expressed spatial distribution of trip departure and arrival areas, particularly showing regional changes in job-related trips. We also found that more factors influence trip chaining in 2010, compared with 2006, and travel cost is more sensitive than travel time in determining travel mode. The research contributes to establish transportation policies based on travel behavior of elderly in a upcoming super-aged society.