• International Journal of Aerospace System Engineering
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• v.4 no.1
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• pp.1-8
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• 2017

This paper proposes the load distribution control allocation technique. The proposed method is designed by combining a conventional control allocation method with load distribution ability in order to reduce the stress acting on ailerons. By designing the weighting matrix as a function of the load distribution rule, the optimal deflection angles of each surface to satisfy both control goal and load distribution can be achieved. Moreover, rule based fault-tolerant control technique is also proposed. The rules are generated by considering both dominant control surfaces and the ratio of load distribution among surfaces. The performance of the proposed method is evaluated through numerical simulations.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.13 no.2
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• pp.27-34
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• 2005

This study is performed to analyze the turbulence distribution of Fev. & Mar. in 2000 by the analysis of the parameters related with flight data of FDR(Flight Data Recorder). In the analysis, we selected the Solid State Flight Data Recorder(SSFDR) & Universal Flight Data Recorder(UFDR) flight data of the exact same aircraft(capacity 120 persons). Through this study, we verified that turbulence is concerned with configuration of the ground and flight situation of aircraft.

• Korean Journal of Agricultural Science
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• v.50 no.3
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• pp.427-435
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• 2023

This study was conducted to evaluate the spraying performance according to the flight conditions of agricultural drones for the development of a variable control system. The analyzed flight conditions comprised six factors: spraying direction, flight speed, altitude, wind speed, wind direction, and rotor rotational speed. The ratio of the area sprayed on the water-sensitive paper was used as the coverage, and the distribution and amount of the coverage were evaluated. The coverage distribution based on the distance from the drone was used to evaluate a spray pattern, and the distribution was expressed as a Gaussian function approximation. In addition, the probability distribution based on coverage was expressed as the cumulative probability via Gamma function approximation to analyze the spraying efficiency in the target area. The results showed that the averaged coverage decreased significantly as the flight speed and wind speed increased, and the wind direction changed the spray pattern without a coverage decrease. This study contributes to the development of a control technique for the precision control system of agricultural drones.

• Journal of Environmental Impact Assessment
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• v.18 no.3
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• pp.143-150
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• 2009

The present study investigates the effects of the flight paths of military aircraft on noise map and its WECPNL(Weighted Equivalent Continuous Perceived Noise Level) distribution. Aircraft noise modeling and simulation have been performed on a Korean military air base by means of INM(Integrated Noise Model) with the input data of airfield location, aircraft specifications, flight paths and aircraft's operation schedules. The result of noise modelling has been verified in comparison with the result of measured noise level. The flight path of military aircraft, as the key parameter of the present study, was modeled by combining takeoff, overfly, approach and touch-and-go modes. The present INM simulations have been conducted for various flight path cases with different takeoff, approach modes and overfly modes. The simulation results showed that the change of flight path can remarkably affect the noise influence region and the WECPNL distribution around the airfield.

• International Journal of Aeronautical and Space Sciences
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• v.6 no.2
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• pp.84-96
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• 2005

Helical tip vortex is known as stable vortex structure, however the specific frequency component of far wake perturbation induces the vortex pairing in hover and axial flight. It is expected that the tip vortex pairing phenomena may happen in transition flight and very low advance ratio flight so that inflow may be most nonuniform in the low advance ratio flight. The objectives of this paper are that a tip-vortex instability during the transition from hover into very low advance ratio forward flight is numerically predicted to understand a physics by using a time-marching free-wake method. To achieve the objectives, numerical method is firstly validated in typical axial and forward flights cases. Present scheme with trim routine can predict airloads and inflow distribution of forward flight with good accuracy. Then, the transition flight condition is calculated. The rotor used in this wake calculation is a small-scale AH-1G model. By using a tip-vortex trajectory tracking method, the tip-vortex pairing process are clearly observed in transient flight($\mu$=0.03) and disappears at a slightly higher advance ratio($\mu$=0.05). According to the steady flight simulation at $\mu$=0.03, it is confirmed the tip-vortex pairing process is continued in the rear part of rotor disk and not occurs in the front part. Time averaged inflow in this case is predicted as smooth distribution.

• Journal of Distribution Science
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• v.18 no.3
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• pp.43-51
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• 2020

Purpose: This study demonstrated and analyzed the role of distributive justice and procedural justice in explaining the organizational effectiveness of flight attendant. In addition, analyzing the role of the airline type in the coordination between reward justice and organizational effectiveness. Research design, data and methodology: An abstract is the impact relationship between the reward justice and organizational effectiveness of flight attendant and the adjustment effect of the airline type was reviewed. To examine these research models, samples were collected from 281flight attendants during Nov, 2019. Results: Reward justice has a positive effect on organizational effectiveness, and the types of airlines have a meaningful adjustment effect in terms of the effect of reward justice on organizational effectiveness. Conclusions: Procedural justice and distributive justice have positive influence on two sub factors of organizational effectiveness of the flight attendant. It suggests that the standards, procedures and processes of compensation must be fair, the degree of effort, the stress or the tension of the flight attendant should be considering, and it is necessary for the airline to respect the personality of the flight attendant and provide them with accurate compensation information in a timely manner. This will increase the awareness of reward.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.29 no.1
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• pp.30-37
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• 2021

This study wanted to confirm whether the DiSC behavior types of student pilots and instructors in the training course of Helicopter pilots affect the flight training achievement. The results of the study are as follows. First, in the distribution of DiSC behavior types of student pilots and instructors, student pilots had the largest number of Dominance with 40.2 percent, while Instructors had the highest number of conscientiousness with 46.5 percent. Second, it was analyzed that the flight training achievement was influenced by the behavior type of student pilots. In basic flight and aircraft type conversion flight, Steadiness had the highest achievement in flight training, and in tactical flight, conscientiousness was the highest. Third, the behavior patterns of student pilots and instructors have been confirmed to have interaction effects in tactical flight.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.1
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• pp.108-117
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• 2017

This paper presents a distribution simulation model for dual purpose improved conventional munitions based on flight test data. A systematic procedure for designing a dispersion simulation model is proposed. A new accumulated broken line graph was suggested for designing the distribution shape. In the process of verification and simulation for the distribution simulation model, verification was performed by first comparing data with firing test results, and an application simulation was then conducted. The Monte Carlo method was used in the simulations, which reflected the relationship between ejection conditions and real distribution data. Before establishing the simulation algorithm, the dominant ejection parameter of the submunitions was examined. The relationships between ejection conditions and distribution results were investigated. Five key distribution parameters were analyzed with respect to the ejection conditions. They reflect the characteristics of clustered particle dynamics and aerodynamics.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.6
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• pp.1043-1050
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• 2010

This paper examined the probabilistic load analysis for the tailplane during pitching maneuvering in the conceptual aircraft design phase. The flight load analysis based on the probabilistic distribution of design variables are compared with the results of the deterministic analysis. Two forms of variable distribution are used in this paper. One is standard normal distribution, the other distribution is calculated from the results of short-period longitudinal equation of aircraft motion. The influence of the distribution parameter on the probabilistic load analysis was investigated and the significant design variables that have an impact on the mean and variance of probabilistic load were identified. The comparison indicates that probabilistic load analysis provides more reliable probabilistic load distribution for the structural design than the traditional deterministic analysis.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.43-52
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• 2020

This paper examines how macroeconomic variables, such as interest rate differences, inflation, exchange rates, economic growth and external debt growth, affect capital flight in the ASEAN-8 countries. We apply a panel data model with fixed effect estimation for the data for eight countries from the period 1994 to 2018. We use the residual approach used by the World Bank to measure the value of capital flight. The results show that the interest rate differences, exchange rates, economic growth and foreign debt growth had a positive and significant effect on outward capital flight. A further implication of this finding is that the interest rate differences, exchange rate, economic growth and foreign debt growth are factors that trigger an increase in capital outflow in the ASEAN-8 countries. Nonetheless, inflation rate is not considered to be the main factor influencing capital flight, as average inflation in the ASEAN-8 countries remains relatively stable. This paper will be beneficial for policymakers in the ASEAN-8 countries and encourage them to constantly pay attention to these four variables, as they significantly influence capital flight, whereas they can disregard the impact of the inflation variable that is not significant in influencing capital flight.