• Journal of Korean Society of Transportation
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• v.27 no.2
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• pp.133-144
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• 2009

In Korea, the ITS project has been progressed to improve traffic mobility and safety. Further, it is to relieve traffic jam by supply real time travel information for drivers and to promote traffic convenience and safety. It is important that the traffic information is provided accurately. This study was conducted outlier elimination and missing data adjustment to improve accuracy of raw data. A method for raise reliability of travel time prediction information was presented. We developed Historical Profile model and adjustment formula to reflect quality of interrupted flow. We predicted travel time by developed Historical Profile model and adjustment formula and verified by comparison between developed model and existing model such as Neural Network model and Kalman Filter model. The results of comparative analysis clarified that developed model and Karlman Filter model similarity predicted in general situation but developed model was more accurate than other models in incident situation.

• Journal of Environmental Impact Assessment
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• v.16 no.6
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• pp.495-502
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• 2007

In Korea, military authorities have neglected to consider impacts of military projects on local communities and natural environment. Moreover, local communities have had difficulties in dealing with the Ministry of National Defense (MND), which was stubborn enough not to implement environmental assessment on their projects. In this situation, recent case, "EIA of Baekgol Division's Howitzer Fire Training Site" in the Supreme Court-in which judges upheld the Higher Court's decision that the division violated the Environmental Impact Assessment law by ignoring to implement EIA-reveals that military projects can no longer forgo environmental assessment. The decision has serious ramifications on the future of Environmental Impact Assessment in military-led projects. This paper examines the proper scope of EIA in military-led projects and, more specifically, fire training site and searches for how to improve it through 'probable error,' a military training method that is applied to real 'howitzer' fire training. Probable error of the artillery field manual is nothing more than an error that exceeded as often as it is not exceeded and its scientific method was demonstrated through real fire tests in the US. Army. If it is applied to improve assessment methods about the proper scope of EIA in military 'howitzer' fire training site, 'probable error' will improve effect prediction, mitigation and reliability.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.4
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• pp.24-36
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• 2015

In the present study, numerical predictions of infrared spectrum of rocket plume with considering effect of particles based on approximation theories were performed by using a line-by-line radiation model with radiation databases. The high-resolution radiation databases were used to predict thermal emission spectra of gas molecules within the rocket plume regime. The particles were modeled as soot particles by using 1st term approximation of Mie theory and Rayleigh approximation. The reliability of modeled effect of soot particles using the two approximation theories was verified, and the spectral radiance of rocket plume was predicted based on the verification. The results were improved in the short wavelength range by considering the effect of soot particles.

• Structural Engineering and Mechanics
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• v.23 no.4
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• pp.409-430
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• 2006

The aim of this study is to investigate the reliability of strong motion records processed by causal and acausal Butterworth filters in comparison to the results obtained from a synthetic accelerogram. For this purpose, the fault parallel component of the Bolu record of the Duzce earthquake is modeled with a sum of exponentially damped sinusoidal components. Noise-free velocities and displacements are then obtained by analytically integrating the synthetic acceleration model. The analytical velocity and displacement signals are used as a standard with which to judge the validity of the signals obtained by filtering with causal and acausal filters and numerically integrating the acceleration model. The results show that the acausal filters are clearly preferable to the causal filters due to the fact that the response spectra obtained from the acausal filters match the spectra obtained from the simulated accelerogram better than that obtained by causal filters. The response spectra are independent from the order of the filters and from the method of integration (whether analytical integration after a spline fit to the synthetic accelerogram or the trapezoidal rule). The response spectra are sensitive to the chosen corner frequency of both the causal and the acausal filters and also to the inclusion of the pads. Accurate prediction of the static residual displacement (SRD) is very important for structures traversing faults in the near-fault regions. The greatest adverse effect of the high pass filters is their removal of the SRD. However, the noise-free displacements obtained by double integrating the synthetic accelerogram analytically preserve the SRD. It is thus apparent that conventional high pass filters should not be used for processing near-fault strong-motion records although they can be reliably used for far-fault records if applied acausally. The ground motion parameters such as ARIAS intensity, HUSID plots, Housner spectral intensity and the duration of strong-motion are found to be insensitive to the causality of filters.

• Journal of Navigation and Port Research
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• v.34 no.8
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• pp.659-667
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• 2010

In this study, we examine features of marine transport environment which shipping companies are facing, analyze the ability to cope with this environment, and present the relationship between the ability and business performances. Then, we demonstrate that diagnosis of shipping environment in the global marine transport environment and preparing to it is very important. Also, we present that the ability to prepare is the main factor to decide the competitive power of the company. This study has a meaning in that the importance of business activities related to environment such like diagnosis of environment, analyzing, management, adaptation, and prediction is presented. Besides, the value of this study is that we analyze the relationship between corresponding ability, strategic execution process and business performance in general.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12A
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• pp.1182-1188
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• 2006

Adaptive OFDM(Orthogonal Frequency Division Multiplexing) improves data capacity and system performance over multipath fading by adaptively changing modulation schemes according to channel state information(CSI). To achieve a good performance in adaptive OFDM systems, CSI should be transmitted from receiver to transmitter in real time through feedback channel. However, practically, the CSI feedback delay d which is the sum of the data processing delay and the propagation delay is not negligible and damages to the reliability of CSI such that the performance of adaptive OFDM is degraded. This paper presents an adaptive OFDM system with a multistep predictor on the frequency axis to effectively compensate the multiple feedback delays $d(\geq2)$. Via computer simulation we compare the proposed scheme and existing adaptive OFDM schemes with respect to data capacity and system performance.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.192-195
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• 2004

Products of gridded surface wind and windstress vectors over the world ocean have been constructed by satellite scatterometer data with highly temporal and spatial resolutions. Even if the ADEOS-II/SeaWinds has supplied surface wind data only for short duration in Apr. to Oct. 2003 to us, it permits us to construct a product with higher resolution together with the Qscat/SeaWinds. In addition to our basic product with its resolution of $1^{\circ}\times1^{\circ}$ in space and daily in time, we try to construct products with $1/2^{\circ}\times1/2^{\circ}$ and semi- and quarter-daily resolution. These products are validated by inter-comparison with in-situ data (TAO and NDBC buoys), and also compared with numerical weather prediction(NWP) ones (NCEP reanalysis). Result reveals that our product has higher reliability in the study area than the NCEP's. For the open ocean regions in the middle and high latitudes where there are no in-situ data, we find that there are clear differences between them. Especially in the southern westerly region of 400-600S, the' wind-stress magnitudes by the NCEP are significantly larger than the others, suggesting that they are overestimated. We also calculate wind-stress curl field that is an important factor for ocean dynamics and focus its spatial character in the northwestern Pacific around Japan. Positive curl areas are found to cover from southwest to northeast in our focus region and almost correspond to the Kuroshio path. It is suggested that the vorticity field in the lower atmosphere is related to the upper oceanic one, and thus an aspect of air-sea interaction process.

• Korean Journal of Veterinary Service
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• v.39 no.1
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• pp.7-12
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• 2016

The Autofom is a equipment for predicting the amount of pig carcasses meat using the 16 ultrasonic sensors to measure in real time and it was established in Dodram LPC in Gyeonggi Province of Korea for the first time. This study was carried out to validate the reliability of Autofom statistically and to establish guideline for developing a analytic formula through comparing the measurement between Autofom and dissection. The ham parts of sixty-six pig carcasses were measured with Autofom and by two experimental performers. The weight means and standard deviations of ham parts including bone by measurements with Autofom and dissection were $10.69{\pm}0.81kg$ and $10.77{\pm}0.94kg$, respectively a strong positive correlation (P<0.01) was identified, with a coefficient of determination ($R^2$) of 0.82. The weight means and standard deviations of lean ham parts by measurements with Autofom and dissection were $7.41{\pm}0.58kg$ and $7.42{\pm}0.89kg$, respectively a strong positive correlation (P<0.01) was identified, with a coefficient of determination ($R^2$) of 0.72. The root mean square errors of two groups were 0.40 and 0.50, respectively.

• Journal of Wetlands Research
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• v.19 no.4
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• pp.459-469
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• 2017

The aim of this study is to improve Potential Flood Damage(PFD) that a flood risk assessment technique used in the National Water Resource Plan comprehensive plan for water resources, which is a top-level plan related to domestic water resources and Flood Risk Indices. Both methods are used to evaluate flood control risks. However, there is a problem of reliability because the problem of data utilization and the damage that occurred in a specific area are applied as an average concept. Therefore, this study improved the method for analysis by components and the flood inundation area was limited to flood damage area. Also, the improvement of the method and the application of the recently provided GIS data to the flood damage prediction area were proposed to improve the usability of the existing method. The existing analysis method and the improved method were applied to the test watershed by each case.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.40 no.4
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• pp.237-247
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• 2003

The Motion Estimation (ME) process is an important part of a video encoding systems since they can significantly reduce bitrate with keeping the output quality of an encoded sequence. Unfortunately this process may dominate the encoding time using straightforward full search algorithm (FS). Up to now, many fast algorithms can reduce the computation complexity by limiting the number of searching locations. This is accomplished at the expense of less accuracy of motion estimation. In this paper, we introduce a new fast motion estimation method based on the spatio-temporal correlation of adjacent blocks. A reliable predicted motion vector (RPMV) is defined. The reliability of RPMV is shown on the basis of motion vectors achieved by FS. The scalar and the direction of RPMV are used in our proposed scheme. The experimental results show that the proposed method Is about l1~14% faster than the nearest neighbor method which is a wellknown conventional fast scheme.