• Asian Journal of Turfgrass Science
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• v.21 no.2
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• pp.127-135
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• 2007

Korea and Japan hosted the FIFA World Cup Soccer Game in 2002. Ten stadiums had been built and more than 30 soccer grounds for practice were renovated in Korea. Sport fields in both countries had problems on cool-season turfgrass growth and quality by summer decline during humid and warm climate especially followed by intensive uses. We measured the effects of air-flow system, which is designed to optimize rootzone soil gas and moisture levels to promote the growth and maintenance turfgrass. This experiment was carried out to verify the effects of the system on soil gas exchange, ground resilience, and turfgrass recovery in turfgrass rootzone. Within 1 or 2hr of operation of the system, rootzone soil gas ($CO_2$, $O_2$) levels returned to natural atmospheric levels completely Soil $CO_2$ levels began to decrease within the first 10 min of operation of the system. The levels were reduced from 1.3 to 0.06% after 30 min, and natural atmospheric levels within 1 hr. When the system was turned off, $CO_2$ levels increased to 0.36% and 0.7% after 5 and 20 hr, respectively. The application of the system did not affect the resilience of turf surface after traffic treatments. Higher traffic treatment resulted in higher surface resilience especially in zoysiagrass plots. Operation of the system had a significant beneficial impact on turf recovery by increased root dry wight and improved turf quality, as compared with the non-operated check plots.

• Journal of Information Processing Systems
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• v.6 no.3
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• pp.375-384
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• 2010

Trajectory modeling is foundational for 4D-Route modeling, conflict detection and air traffic flow management. This paper proposes a novel algorithm based Vincenty's fomulas for trajectory calculation, combined with the Dijkstra algorithm and Vincenty's formulas. Using flight plan simulations our experimental results show that our method of En-route trajectory calculation exhibits much improved performance in accuracy.

• Journal of Advanced Navigation Technology
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• v.14 no.4
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• pp.489-494
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• 2010

According to the recent increase in air traffic more efficient air traffic control automation is required. Aeronautical traffic environment is different from the common traffic environment since it exist controller for control of aircraft And controller have to control jurisdiction hand-off by manual when aircraft move to the other sector. This paper proposes the automatic control jurisdiction hand-off algorithm for efficient air traffic flow management. It is sector distinction algorithm that aircraft move sector to the other sector it recognized sector and then give permission to authorized controller. As a simulation result, so unlilke simply manual control sector hand-off of existing algorithm. we confirmed that proposed algorithm in this paper can do air traffic control more efficiently by performing automatic aircraft. control sector hand-off.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.9
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• pp.4287-4306
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• 2016

Network resilience provides an effective way to overcome the problem of network failure and is crucial to Internet protocol (IP) network management. As one of the main challenges in network resilience, recovering from link failure is important to maintain the constancy of packets being transmitted. However, existing failure recovery approaches do not handle the traffic engineering problem (e.g., tuning the routing-protocol parameters to optimize the rerouting traffic flow), which may cause serious congestions. Moreover, as the lack of QoS (quality of service) restrictions may lead to invalid rerouting traffic, the QoS requirements (e.g., bandwidth and delay) should also be taken into account when recovering the failed links. In this paper, we first develop a probabilistically correlated failure model that can accurately reflect the correlation between link failures, with which we can choose reliable backup paths (BPs). Then we construct a mathematical model for the failure recovery problem, which takes maximum rerouting traffic as the optimizing objective and the QoS requirements as the constraints. Moreover, we propose a heuristic algorithm for link failure recovery, which adopts the improved k shortest path algorithm to splice the single BP and supplies more protection resources for the links with higher priority. We also prove the correctness of the proposed algorithm. Moreover, the time and space complexity are also analyzed. Simulation results under NS2 show that the proposed algorithm improves the link failure recovery rate and increases the QoS satisfaction rate significantly.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.22 no.2
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• pp.53-59
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• 2014

Simultaneous parallel approaches in all weather conditions should be applied to manage efficiently increasing volume of air traffic flow and solve the problem of delayed arrivals. But All of the airports which have closely-spaced parallel-runways in Korea don't meet the interval-standards for IFR parallel approaches. In that regard, more accurate and safer System should be applied for the Korean airports. GNSS was adopted as an international standard of the next-generation navigation system and many studies and master plans have been activated by stages in Korea. In this paper, the current state of the domestic airports will be analyzed focusing on the interval of parallel runways and future specification of both flight operation system and air-side management will be recommended.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.32 no.1
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• pp.61-70
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• 2024

In response to the continuously increasing demand for air travel, various studies are being conducted. This research focuses on the design of a simulation model for improving airport slot allocation in the strategic phase. It addresses three aspects of model design, introducing considerations such as the objective function. Additionally, it explains the conceptual procedures for the overall simulation operation and detailed processes within the model including input and output data. Emphasizing the SAL, this study excludes policy and qualitative judgments from its scope. The target airport for application will be confirmed in future research. This study marks a crucial first step toward optimizing air traffic flow, with expectations of contributing to the enhancement of operational efficiency at airports.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.6
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• pp.77-90
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• 2015

An increasing number of vehicles is causing various traffic problems such as chronic congestion of highways and air pollution. Local governments have been managing traffic by constructing systems such as Intelligent Transport Systems (ITS) and Advanced Traffic Management Systems (ATMS) to relieve such problems, but construction of an infrastructure-based traffic system is insufficient in resolving chronic traffic problems. A more sophisticated system with enhanced operational management capabilities added to the existing facilities is necessary at this point. As traffic patterns of the urban traffic flow is time-specific due to the different vehicle populations throughout the time of the day, a local network-wide signal operation plan that can manage such situation-specific traffic patterns is deemed to be necessary. Therefore, this study is conducted for the purpose of establishment of a plan for contextual signal control management through signal optimization at the network level after setting the Frame Signal in accordance to the traffic patterns gathered from the short-term traffic forecast data as a means to mitigate the problems with existing standardized signal operations.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.3
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• pp.215-222
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• 2022

The purpose of air traffic flow management is to balance demand and capacity in the national airspace, and its performance relies on an accurate capacity prediction of the airport or airspace. This paper developed a regression model that predicts the number of aircraft actually departing and arriving in a terminal maneuvering area. The regression model is based on a boosting ensemble learning algorithm that learns past aircraft operational data such as time, weather, scheduled demand, and unfulfilled demand at a specific airport in the terminal maneuvering area. The developed model was tested using historical departure and arrival flight data at Incheon International Airport, and the coefficient of determination is greater than 0.95. Also, the capacity of the terminal maneuvering area of interest is implicitly predicted by using the model.

• Journal of ILASS-Korea
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• v.21 no.4
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• pp.214-222
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• 2016

Changes in road infrastructure affect driving patterns and pollutant emission characteristics. we analyzed the changes in driving patterns and pollutant emission characteristics of the driving route via measured driving patterns at year 2009 and 2016. Since 2009, there has been an increase in population and traffic demand, including residential areas and industrial facilities. Traffic conditions were improved such as the opening of the highway Inter-Change to Seoul and the construction of underground driveway. As a result, the average vehicle speed increased. More detail comparisons have made on the changes of the underground driveway section and the crossroad section, which are expected to have significant changes in the transportation infrastructure. The vehicle speed distribution of the underground driveway changed from low speed to high speed, and the increase of the time spent at the high speed and high load caused the increase of NOx emissions. The vehicle speed also increased at the crossroad section, and the consequence NOx and $CO_2$ emissions decreased. It is mainly because the decreased time spent at idle, which results from the proper traffic demand management at this area.

• 한국항공운항학회:학술대회논문집
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• 2016.05a
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• pp.269-275
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• 2016

This paper considers the arrival, airport and departure capacity as a whole, through which, the network effect between airports is fully emphasized, the flight action is coordinated, and the flight demand pattern is reasonably assigned. The optimization problem of flight queues in multi-airport is studied in detail; the mathematical model of multi-airport opening non-real time flow management in terminal area is established, and related problems such as the parameters, the simplification and the solving of the model are discussed in detail to some extent. Appropriate decision making variables are taken to make the multi-airport network system linear 0-1 integer programming model, thus, the solving of the model is available and the central flow management is realized. The heuristic implicit enumeration presented in this paper can effectively solve this kind of problems. Through the simulation of some airports network system, we not only validate the algorithm presented in this paper, but also give a deep analysis of the results, which would produce reference for later practicable use. The simulation proves that this algorithm offers a good way to settle the problem of multi-airport flight queue optimization in air traffic management automation system in terminal area.