• Communications for Statistical Applications and Methods
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• v.24 no.5
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• pp.519-531
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• 2017

We consider goodness-of-fit test statistics for Weibull distributions when data are randomly censored and the parameters are unknown. Koziol and Green (Biometrika, 63, 465-474, 1976) proposed the $Cram\acute{e}r$-von Mises statistic's randomly censored version for a simple hypothesis based on the Kaplan-Meier product limit of the distribution function. We apply their idea to the other statistics based on the empirical distribution function such as the Kolmogorov-Smirnov and Liao and Shimokawa (Journal of Statistical Computation and Simulation, 64, 23-48, 1999) statistics. The latter is a hybrid of the Kolmogorov-Smirnov, $Cram\acute{e}r$-von Mises, and Anderson-Darling statistics. These statistics as well as the Koziol-Green statistic are considered as test statistics for randomly censored Weibull distributions with estimated parameters. The null distributions depend on the estimation method since the test statistics are not distribution free when the parameters are estimated. Maximum likelihood estimation and the graphical plotting method with the least squares are considered for parameter estimation. A simulation study enables the Liao-Shimokawa statistic to show a relatively high power in many alternatives; however, the null distribution heavily depends on the parameter estimation. Meanwhile, the Koziol-Green statistic provides moderate power and the null distribution does not significantly change upon the parameter estimation.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.5
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• pp.409-421
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• 2017

Recently Unmanned Aerial Vehicle (UAV) technology offers new opportunities for assessing crop growth condition using UAV imagery. The objective of this study was to select optimal vegetation indices and regression model for estimating of rice growth using UAV images. This study was conducted using a fixed-wing UAV (Model : Ebee) with Cannon S110 and Cannon IXUS camera during farming season in 2016 on the experiment field of National Institute of Crop Science. Before heading stage of rice, there were strong relationships between rice growth parameters (plant height, dry weight and LAI (Leaf Area Index)) and NDVI (Normalized Difference Vegetation Index) using natural exponential function ($R{\geq}0.97$). After heading stage, there were strong relationships between rice dry weight and NDVI, gNDVI (green NDVI), RVI (Ratio Vegetation Index), CI-G (Chlorophyll Index-Green) using quadratic function ($R{\leq}-0.98$). There were no apparent relationships between rice growth parameters and vegetation indices using only Red-Green-Blue band images.

• Journal of the Korean Data and Information Science Society
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• v.20 no.6
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• pp.1119-1127
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• 2009

In PGA golf, total prize money and average score are good response variable related to golf skills such as driving distance, green in regulation and putts per green in regulation. But it's not easy to predict the winner of coming tournament. Thus I applied Neural Networks which has pretty good advantages for non-linear complex modeling to binary data. In neural network architectures, I applied NRBF and MLP architecture model for binary data which represent who had a win or not.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.4
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• pp.310-318
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• 2004

For many industrial problems originating from aerodynamic noise, noise prediction techniques, reliable and easy to apply, would be of great value to engineers and manufacturers. General algorithm is presented for the prediction of internal flow-induced noise from quick opening throttle valve in an automotive engine. This algorithm is based on the integral formula derived by using the General Green Function, Lighthill's acoustic analogy and Curle's extension of Lighthill's. Novel approach of this algorithm is that the integral formula is so arranged as to predict frequency-domain acoustic signal at any location in a duct by using unsteady flow data in space and time, which can be provided by the Computational Fluid Dynamics Techniques. This semi-analytic model is applied to the prediction of internal aerodynamic noise from a throttle valve in an automotive engine. The predicted noise levels from the throttle valve show good agreement with actual measurements. The results show that the dipole noise is dominant in this phenomena and the origin of noise sources is attributed to the anti-vortex lines formed in the down-stream from a throttle valve. This illustrative computation shows that the current method permits generalized predictions of flow noise generated by bluff bodies and turbulence in flow ducts.

• The Journal of the Acoustical Society of Korea
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• v.22 no.4E
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• pp.183-196
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• 2003

General algorithm is developed for the prediction of internal flow-induced noise. This algorithm is based on the integral formula derived by using the General Green Function, Lighthill's acoustic analogy and Curl's extension of Lighthill's. Novel approach of this algorithm is that the integral formula is so arranged as to predict frequency-domain acoustic signal at any location in a duct by using unsteady flow data in space and time, which can be provided by the Computational Fluid Dynamics Techniques. This semi-analytic model is applied to the prediction of internal aerodynamic noise from a throttle valve in an automotive engine. The predicted noise levels from the throttle valve are compared with actual measurements. This illustrative computation shows that the current method penn its generalized predictions of flow noise generated by bluff bodies and turbulence in flow ducts.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.9
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• pp.46-55
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• 1992

This paper propose how to calculate the capacitance for VLSI interconnection lines in multi-dielectric layer. The proposed method is a expansive form of 3-dimensional direct intergral method developed in single-dielectric layer. We took into consideration the effect of multi-dielectric layer by using additional boundary condition instead of modified Green's function. It is used the potential equations in line surface and the electric field equations in dielectric interface as the boundary condition. RC delay time for interconnection line of multi-dielectric layer is obtained from the calculated capacitance value. At this time, we are used Al and WSiS12T as interconnection materials.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.677-680
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• 2008

The paper deals with the analysis of radiation characteristics of antenna in the multi-layered media structures. The dyadic Green's function for three layer medium is complex because the Green's functions belonging to the kernel of the integral equation are expressed as Sommerfeld integrals, in which surface wave effects are automatically included. When certain condition are met, the integral can be evaluated approximated by the method of Saddle-point integration. In this study, we propose a method to calculate a radiation pattern for several antennas by using the method of Saddle-point integration. Numerical results show how the radiation characteristics are affected by parameter of dielectric media.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.2
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• pp.54-61
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• 1998

The subsurface environment of the root zone area can set the stae for "do or die" of the turfgrass plant. The good condition of the greens is verified by their physical properties. Therefore, this study was carried to evaluate on the existing green of Hwasan C.C. by undisturbed soil Core Anaysis. We completed the ISTRC SYSTEM BenchMarking of the undisturbed core samples taken from Green #1, Green #5, Green #9-"Best" area, and Green #9-"Stressed" area for the Hwasan C.C.. It was also our understanding that the greens were in "good" to "very good" conditioni. THe exception might be Green #9-"Stress" area, which was the stressed area. The stressed area was confined to a ridge across Green #9. The organic content test results comfirmed the development of organic layering in depth 0-2.5cm. For the amount of compaction in the upper root zones and te development of the green's respective organic layers, the infiltration rates were high in Green #1, Green #5, and Green #9 "Stressed" area. The depicted aerificaton hole might be the probable cause of the relatively high infiltraton rate. Green #9-"Best" area had a tested infiltration rate of 18.75cm/hr. Either this area had not been aerified, or the undisturbed sample did not contain a aerification cavity. The water retention capacity of the undisturbed samples was good. When the greens were first constructed, the original root zone mix had been relatively low water retention properties. And the bulk density and the porosity of the undisturbed samples were good. In the result, all the greens were similar except for the infiltration. Thus, we supposed that Green #9-"Stressed" area might be ainly influenced by the amount of irrigation water and the configuration of the green's surface. There had been a reduction in the amount of irrigation water as the water retention capacity in the greens was promoted. Especially, it had gradually become more of a problem as the green had matured in Green #9-"Stressed" area. Because Green #9-"Stressed" area was a ridge area. The reduction in the amount of irrigation water might be the probable cause of the stress in Green #9-"Stressed" area. Our final observation related to the soil texture and the particle size distribution of the sand. Though and sand contant of all the tested greens were good, the gravel content of them exceeded ISTRC Guidelines. In particle size distribution of the sand, the very coarse and the coarse content of all the tested greens exceeded, but the rest was insufficient. The stability is a function of the material retained on the 0.25mm mesh screen. But, the content of all the tested greens was very insufficient. Though all the greens was serviceable, the coarse root zone sands, such as the sand in the tested greens, tended to be "unstable". Thus, we recommend using a topdressing/aerification sand which should be more in line with ISTRC/USGA Guidelines.;unstable". Thus, we recommend using a topdressing/aerification sand which should be more in line with ISTRC/USGA Guidelines.ines.

• KIEAE Journal
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• v.14 no.2
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• pp.11-19
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• 2014

Building energy consumption takes up almost 25% of the total energy consumption. Therefore, diversified ways, such as improving wall and window insulation, have been considered to reduce building energy consumption. Recently, green roof system has been explored as an effective alternative for dealing with reducing heating and cooling energy, thermal island effect and improving water quality. However, recent studies regarding a green roof system have only focused on building energy reduction without considering the applied usage, location, and story of the green roof system. Therefore, this study pays attention to the heating and cooling energy in relation to the applied usage, location, and story of a green roof system for investigating its impact on energy reduction. The result of simulations show that the reduction in heating energy consumption is higher when applied to Cherwon-gun province which has a continental climate condition, compared to the city of Busan that is distinguished by its warm climate. Cooling energy saving turns out to be higher when the green roof system is applied to Busan in comparison with Cherwon. As for the applied usage or function of the building, residential space acquires the highest heating and cooling energy saving effect rather than commerce, educational or office space because of HVAC's running time based on usage. When it comes to the story of the green roof, both heating and cooling energy saving become the highest when the green roof is applied to single-storied buildings. The reason is that single story building is affected by the ground largely. Generally, the variations of heating energy consumption are larger than the cooling energy consumption. The outcome of the simulations, when a green roof system is applied, indicates that the energy consumption reduction rate is dynamically responding to the applied usage, location, and story. Therefore, these factors should be counted closely for maximizing the reduction of energy consumption through green roof systems.

• Journal of Photoscience
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• v.1 no.1
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• pp.75-82
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• 1994

General features of the fluorescence depolarization are briefly reviewed. Molecular rotations and electronic excitation transports are considered to account for the fluorescence depolarization. Various molecular systems studied by the fluorescence depolarization are described. The FiSrster theory which forms a basis for the energy transfer is revisited. Several theoretical treatments for the fluorescence depolarization in liquid and solid phases such as classical hydrodynamics, probability distribution function, Green's function formalism, molecular dynamics simulation and Monte Carlo methods are introduced.