• Journal of Korean Society of Coastal and Ocean Engineers
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• v.6 no.3
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• pp.216-225
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• 1994

By use of laboratory experiment data set for an elliptic shoal by Berkhoff et al. (1982), both accuracy and Performance tests of numerical results between PCGM (Preconditioned Conjugate Gradient Method) and PA(Parabolic Approximation) are compared. Although both results show good agreement with the experimental data the PA model gives better reproduction of the relatively high amplitudes in the section 4-5 downwave of the shoal, in comparison with the PCGM. The PA model has been proved to be a useful tool for predicting wave transformationsin large shallow water region, but it can be applied only to the case of negligible reflection. On the other hand, there is a need to improve the computational efficiency of the PCGM model which is a finite difference scheme directly derived from the mild slope equation and can handle reflection. By taking the results of th PA model as an input data of the PCGM, the CPU time can be reduced by about 40%.

• Korean Journal of Remote Sensing
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• v.18 no.3
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• pp.127-139
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• 2002

A comparison was made between the chlorophyll $\alpha$ and suspended solid (SS) retrievals from OSMI and SeaWiFS sensor to chlorophyll $\alpha$ and SS values determined with the standard method during the NFRDI's research cruises. The percentage of organic and inorganic materials from the SS was calculated to study the contribution of turbid water in the northern part of the East China Sea. The open sea waters in the Kuroshio regions of the East China Sea showed relatively higher concentration of volatile SS. However, towards the northwestern part of the East China Sea, the situation became much more optically different with the non-volatile SS from the Yangtze river and the sea bottom sources in the sea in winter and spring seasons. Furthermore, in order to indirectly detect low salinity water with high turbidity, which related to the Yangtze river using remote sensed data from the satellites, a comparison between the results of the band ratio(nLw 490nm/nLw 555nm) of SeaWiFS(OSMI) and the distribution of low salinity around the Jeju Island was presented.

• Korean Journal of Remote Sensing
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• v.14 no.3
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• pp.262-276
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• 1998

The paper first describes the atmospheric correction algorithm for the Ocean Color and Temperature Scanner (OCTS) visible band data used at Earth Observation Center (EOC) of National Space Development Agenrr of japan (NASDA). It uses 10 candidate aerosol models including "Asian dust model" introduced in consideration of the unique feature of aerosols over the east Asian waters. Based on the observations at 670 and 865 nm bands where the reflectance of the water body can be discarded, the algorithm selects a pair of aerosol models that accounts best for the observed spectral reflectances to synthesize the aerosol reflectance in other bands. The paper also evaluates the performance of the algorithm by comparing the satellite estimates of water-leaving radiance and chlorophyll-a concentration with selected buoy- and ship-measured data. In comparison with the old CZCS-type atmospheric correction algorithm where the aerosol reflectance is assumed to be spectrally independent, the OCTS algorithm records factor 2-3 less error in estimating the normalized water-leaving radiances. In terms of chlorophyll-a concentration estimation, however, the accuracy stays very similar compared to that of the CZCS-type algorithm. This is considered to be due to the nature of in-water algorithm which relies on spectral ratio of water-leaving radiances.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.150-150
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• 2018

The Numerical Weather Prediction (NWP) models provide information for weather forecasts. The highly nonlinear and complex interactions in the atmosphere are simplified in meteorological models through approximations and parameterization. Therefore, the simplifications may lead to biases and errors in model results. Although the models have improved over time, the biased outputs of these models are still a matter of concern in meteorological and hydrological studies. Thus, bias removal is an essential step prior to using outputs of atmospheric models. The main idea of statistical bias correction methods is to develop a statistical relationship between modeled and observed variables over the same historical period. The Model Output Statistics (MOS) would be desirable to better match the real time forecast data with observation records. Statistical post-processing methods relate model outputs to the observed values at the sites of interest. In this study three methods are used to remove the possible biases of the real-time outputs of the Weather Research and Forecast (WRF) model in Imjin basin (North and South Korea). The post-processing techniques include the Linear Regression (LR), Linear Scaling (LS) and Power Scaling (PS) methods. The MOS techniques used in this study include three main steps: preprocessing of the historical data in training set, development of the equations, and application of the equations for the validation set. The expected results show the accuracy improvement of the real-time forecast data before and after bias correction. The comparison of the different methods will clarify the best method for the purpose of the forecast skill enhancement in a real-time case study.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.805-808
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• 2014

The DBMS is a database management software system to access by people. It is an open source DBMS, such as MySQL and commercial services, such as ORACLE. Since MySQL has been acquired by Oracle, MariaDB released increase demand. NoSQL also are increasing, the trend is of interest, depending on the circumstances. Based on the same type of mass data, Depending on the performance comparison between the open source DBMS is required, and The study compared the performance between MariaDB and MongoDB. This paper proposes a DBMS for big data to process.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.35.2-35.2
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• 2018

Using the K-band Multi-object Spectrograph (KMOS) at the Very Large Telescope (VLT), the KMOS Redshift One Spectroscopic Survey (KROSS) has gathered integral-field data for ~800 star-forming galaxies at a redshift z~1, when the universe was roughly half its current age and forming the bulk of its stars. With spatially-resolved observations, KROSS reveals galaxies that are both gas-rich and highly turbulent. It is possible to derive the observed and baryonic Tully-Fisher (luminosity - rotation velocity) relations, thus constraining the mass-to-light ratios and total (luminous + dark) masses of the galaxies. This in turn highlights the dependence of the relation zero-point on the degree of rotational support of the galaxies (rotational velocity to velocity dispersion ratio). By degrading and analogously analysing integral-field data of hundreds of local galaxies from the Sydney-AAO Multi-object Integral-field Spectrograph (SAMI) survey, a robust comparison z=0 Tully-Fisher relation can also be derived, thus further constraining the luminous and dark mass growth of disk galaxies over the last 7 billions years. This unique comparison also reveals that systematic effects associated with sample selection and analysis methods are as large as the effects expected from cosmological evolution, and thus that most other comparisons employing heterogeneous data and/or methods can safely be ignored.

• East Asian Journal of Business Economics (EAJBE)
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• v.9 no.2
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• pp.31-42
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• 2021

Purpose- This research's purpose is to give implications on how to increase employee satisfaction and organizational commitment of Korean employees using internal marketing. To do that this study analyzes relationships among variables and analyses mediating effect of satisfaction. Also, this study wants to analyze economic performance change of business as a moderator so group comparison between an economic slump and economic recovery is included. Research design, data, and methodology- To analyze relationships among internal marketing, employee satisfaction and organizational commitment of Korean employees, this study used the 7th KRIVET's HCCP data of employee and firm's financial statements data. And conducted CFA, SEM and group comparison analysis by using AMOS 21. Result- According to the empirical results, employee satisfaction mediates between internal marketing and organizational commitment. However, trust was the only significant antecedent that give a positive influence on employee satisfaction. And employee satisfaction increases organizational commitment. Also, economic performance change of business does significantly deteriorate relationships. Conclusion- Based on this study result, implications to manage the organizational commitment of Korean employees are discussed. Especially, the effect of employee satisfaction and trust discussed. Also, economic performance group which is an economic slump and economic recovery differentiation is highlighted. Therefore the cautious approach is needed in managing employee attitude to job and organization is needed

• Coupled systems mechanics
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• v.11 no.2
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• pp.121-132
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• 2022

Wastewater treatment plants (WWTPs) are designed and built to remove contaminants from wastewater. WWTPs are composed of various facilities equipped with hydro-mechanical and electrical equipment. This paper presents a comparison of two different approaches for WWTPs modelling. Static modelling is suitable for determining the dimensions of facilities and equipment capacity. The special significance of this approach is for the design of new plants, i.e., when a very small number of input data on the quantities and composition of the influent wastewater is available. Dynamic modelling is expensive, time consuming and requires great expertise in the use of simulators, models and very good understanding of the treatment processes. Also, dynamic modelling is very important to use for optimization, consideration of future scenarios and also possible scenarios on the plant. The comparison of two approaches was made on the input data from the biggest and most important plant in Bosnia and Herzegovina (B&H)-WWTP Butila (Sarajevo). The main idea is to show the differences between two demanding accesses. It is important to know how to apply an adequate approach to research and solve the set task. The II phase of the plant Butila, which includes the removal of nutrients, is planned in several years and therefore the importance of research has increased.

• Nuclear Engineering and Technology
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• v.53 no.8
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• pp.2445-2453
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• 2021

Since the nuclear data forms a vital component in reactor physics computations, the nuclear community needs processing codes as tools for translating the Evaluated Nuclear Data Files (ENDF) to simulate nuclear-related problems such as an ACE format that is used for MCNP. Errors, inaccuracies or discrepancies in library processing may lead to a calculation that disagrees with the experimentally measured benchmark. This paper provides an overview of the processing and preparation of ENDF/B-VIII.0 incident neutron data with NECP-Atlas and NJOY codes for implementation in the MCNP code. The resulting libraries are statistically inter-compared and tested by conducting benchmark calculations, as the mutualcomparison is a source of strong feedback for further improvements in processing procedures. The database of the benchmark experiments is based on a selection taken from the International Handbook of Evaluated Criticality Safety Benchmark Experiments (ICSBEP handbook) and those proposed by Russell D. Mosteller. In general, there is quite good agreement between the NECP-Atlas1.2 and NJOY21^(1.0.0.json) results with no substantial differences, if the correct input parameters are used.

• Journal of Software Assessment and Valuation
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• v.17 no.1
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• pp.17-24
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• 2021

There is a problem that unknown paintings are sophisticated in the level of forgery, making it difficult for even experts to determine whether they are genuine or counterfeit. These problems can be suspected of forgery even if the genuine product is submitted, which can lead to a decline in the value of the work and the artist. To address these issues, in this paper, we propose a system to classify chromaticity data among extracted data through objective analysis into quadrants, extracting comparisons and intersections, and estimating authors of unknown paintings using XRF and hyperspectral spectrum data from corresponding points.