• Journal of Mechanical Science and Technology
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• v.17 no.11
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• pp.1812-1819
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• 2003

This paper presents the effect of injection pressure on the atomization characteristics of high-pressure injector in a direct injection gasoline engine both experimentally and numerically. The atomization characteristics such as mean droplet size, mean velocity, and velocity distribution were measured by phase Doppler particle analyzer. The spray development, spray penetration, and global spray structure were visualized using a laser sheet method. In order to investigate the atomization process in more detail, the calculations with the LISA-DDB hybrid model were performed. The results provide the effect of injection pressure on the macroscopic and microscopic behaviors such as spray development, spray penetration, mean droplet size, and mean velocity distribution. It is revealed that the accuracy of prediction is promoted by using the LISA-DDB hybrid breakup model, comparing to the original LISA model or TAB model alone. And the characteristics of the primary and secondary breakups have been investigated by numerical approach.

• Nuclear Engineering and Technology
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• v.34 no.6
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• pp.533-544
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• 2002

The neutron induced nuclear data for Mo-95, Tc-99, Ru-101 and Rh-103 was calculated and evaluated in the fast energy region. The energy dependent optical model potential parameters were extracted based on the recent experimental data and applied up to 20 MeV. The s-wave strength function was calculated from the parameters. Spherical optical model, statistical model in equilibrium energy, multistep direct and multistep compound model in pre-equilibrium energy and direct capture model were used in the calculation. The theoretically calculated cross sections were compared with the experimental data and the evaluated files The model- calculated total and capture cross sections were in good agreement with the reference experimental data. The direct capture contribution improved the capture cross sections in pre- equilibrium region. The evaluated cross section results were compiled to ENDF-6 format and will improve the ENDF/B-Vl.

• Nuclear Engineering and Technology
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• v.35 no.1
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• pp.35-44
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• 2003

The neutron induced nuclear data for Eu-153, Gd-155 and Cd-157 are calculated and evaluated in the high energy region. The evaluation procedure for deformed nuclei is setup by using Ecis-Empire codes. The energy dependent optical model potential parameters are searched based on the recent experimental data and applied up to 20 MeV. Optical model, full featured Hauser-Feshbach model and multistep direct and multistep compound model are used in the calculation. The direct-semidirect capture model and the direct coupled-channels contribution to discrete levels are introduced to improve the capture and inelastic scattering cross sections. The theoretically calculated cross sections are compared with the experimental data and the evaluated files. The model-calculated total and capture cross sections are in good agreement with the reference experimental data. The evaluated cross section results are compiled to ENDF-6 format and are expected to improve the ENDF/B-Vl.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.6
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• pp.65-71
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• 2018

The Long-Term Hydrologic Impact Assessment (L-THIA) model is a quick and straightforward analysis tool to estimate direct runoff and nonpoint source pollution. L-THIA was originally implemented as a spreadsheet application. GIS-based versions of L-THIA have been developed in ArcView 3 and upgraded to ArcGIS 9. However, a major upgrade was required for L-THIA to operate in the current version of ArcGIS and to provide more options in runoff and NPS estimation. An updated L-THIA interfaced with ArcGIS 10.0 and 10.1 has been developed in the study as an ArcGIS Desktop Tool. The model provides a user-friendly interface, easy access to the model parameters, and an automated watershed delineation process. The model allows use of precipitation data from multiple gauge locations for the watershed when a watershed is large enough to have more than one precipitation gauge station. The model estimated annual direct runoff well for our study area compared to separated direct runoff in the calibration and validation periods of ten and nine years. The ArcL-THIA, with a user-friendly interface and enhanced functions, is expected to be a decision support model requiring less effort for GIS processes or to be a useful educational hydrology model.

• Journal of the Korean Society of Costume
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• v.66 no.4
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• pp.111-127
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• 2016

The study aims to examine the forms of 'image expression' and utilization of model poses in fashion photos, and to delve into the characteristics and the intents that make certain model poses effective in expressing an image. The study used the fashion photos in the fashion magazine, Vogue, to analyze the different model poses used to express different images. The results are as follows. First, image expression forms in fashion photos were categorized into 'direct product suggestion expression form', 'sensual image expression form', 'sexual image expression form', 'story telling expression form', 'everyday situation expression form', and 'fantastic image expression form'. The different utilization types of model poses were categorized into 'type utilizing intangible elements', 'type utilizing complicated elements', 'type utilizing living organisms', 'type utilizing props', 'type utilizing clothes', 'type utilizing location', 'type utilizing accessories', and 'type utilizing products'. Second, the most common expression form for fashion photos used in advertisements was the 'direct product suggestion expression form', which was followed by the sensual image expression form. The most popular form used in the editorial fashion photos was the direct suggestion product expression form, which was followed by the story telling expression form. Third, the most common model pose type for direct product suggestion form was the 'type utilizing product'. Fourth, 'direct product suggestion expression form' was mostly used in editorial fashion photos. The most common utilization types of model poses were 'type utilizing clothes', 'type utilizing props', and 'type utilizing place'.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.2
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• pp.149-154
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• 2000

The objectives of this study of Hanwoo (Korean Cattle) were 1) to estimate genetic parameters for direct and maternal genetic effects for birth weight, weaning weight, and six months weight which can be used for genetic evaluations and 2) to compare models with and without grandmatemal effects. Data were obtained from the National Livestock Research Institute in Rural Development Administration (RDA) of Korea and were used to estimate genetic parameters for birth weight (BW, n=10,889), weaning weight at 120-d (WW, n=8,637), and six month weight (W6, n=8,478) in Hanwoo. Total number of animals in pedigrees was 14,949. A single-trait animal model was initially used to obtain starting values for multiple-trait animal models. Estimates of genetic parameters were obtained with MTDFREML using animal models and derivative-free REML (Boldman et al., 1995). Estimates of direct heritability for BW, WW, and W6 analyzed as single-traits were 0.09, 0.03, and 0.02 from Model 3 which included direct and maternal genetic, maternal permanental environmental effects, and effects due to sire ${\times}$ region ${\times}$ year-season interaction, respectively. Ignoring sire ${\times}$ region ${\times}$ year-season interaction effect in the model (Model 2) resulted in larger estimates for direct heritability than for Model 3. Estimates of maternal heritability for BW, WW and W6 were 0.04, 0.05, and 0.07 from Model 3, respectively. The estimates of direct-maternal genetic correlation were positive for BW, WW, and W6 with Model 3 but were negative with Model 2 for WW and W6. Estimates of direct genetic correlations between BW and WW, BW and W6, and WW and W6 were large: 0.52, 0.45, and 0.90, respectively. Genetic correlations were also large and positive for maternal effects for BW with maternal effects for WW and W6 (0.69 and 0.74), and even larger for WW with W6 (0.97). The log likelihood values were the same for models including grandmatemal effects as for models including maternal effects for all traits. These results indicate that grandmatemal effects are not important for these traits for Hanwoo or that the data structure was not adequate for estimating parameters for a grandmatemal model.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.2
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• pp.153-158
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• 2004

Data containing 14,188 lactation and reproductive records of Korean Holstein cows at first parity distributed across 3,734 herd-year-season groups were analyzed to get genetic (co)variance estimates for milk yield, fat yield, calving ease, and days open. Milk and Fat yields were adjusted to 305 d. Heritabilities and genetic correlations were estimated in two different animal models on which were included direct genetic effects (Model 1) and direct+maternal genetic effects (Model 2) using REML algorithms. Milk and fat yields were affected by age at first calving as linear and quadratic. Heritability estimates of direct effects were 0.25 for milk yield, 0.17 for fat yield, 0.03 for calving ease and 0.03 for days open in Model 2. These estimates for maternal effects were 0.05, 0.08, 0.04 and less than 0.01 for each corresponding trait. Milk productions at first lactation were to show genetically favorable correlation with calving ease and days open for direct genetic effects (-0.24 - -0.11). Moreover, calving ease was correlated with days open of 0.30 for direct genetic effects. Correlations between direct and maternal effects for each trait were negatively correlated (-0.63 - -0.32). This study suggested that maternal additive genetic variance would be not ignorable for genetic evaluation of milk production as well as reproductive traits such as calving ease and days open at first parity. Furthermore, difficult calving would genetically influence the next conception.

• The Journal of Information Systems
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• v.12 no.1
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• pp.47-66
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• 2003

This study was examined the relationship between the exogenous and endogenous variables in our model to measure ERP system performance using path analysis. The exogenous variables are system quality, user participation, user training, top management support and self-efficacy, and the endogenous variables are system usage, user satisfaction, and work efficiency. The results of the study are shown as follows. First, all the exogenous variables in our model have a direct effect on user satisfaction, and system quality, training, and self-efficacy have a direct effect on system usage. Second, system usage has a direct effect on user satisfaction and user satisfaction has a direct effect on work efficiency. The findings show that the exogenous variables in the model are important to increase ERP implementation success.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.653-661
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• 2017

This study compares and analyzes the operation costs of traditional and direct delivery strategies considering carbon emissions. For the determination of minimum operation costs and order quantity, we use the Economic Order Quantity (EOQ) model, which is the proper method for calculate the operation costs by logistics strategy. Using the classical EOQ model, we expand the EOQ model considering carbon emissions and domestic logistics environment. We conduct an empirical study on two agri-food logistics strategies under limitation of the carbon emissions using the expanded EOQ model. From the results of the empirical study, we find that the operation costs of direct delivery strategy are about 50% lower than those of the traditional strategy. Economic order quantity is also smaller than that of the traditional strategy. These results indicate that agri-food products can be transported quickly and freshly under direct delivery strategy. Consequently, considering carbon emissions, direct delivery logistics strategy are analyzed to have more positive effect on economic and environmental issues than existing logistics strategy. It is judged that direct strategy will also increase the freshness of agricultural products.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.2
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• pp.99-106
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• 2003

A new reconfigurable model following flight control method based on direct adaptive scheme is presented. Using the timescale separation principle, both the inner-loop and the outer-loop states are controlled simultaneously. For the timescale separation assumption to be satisfied, the inner-loop model dynamics is set to be fast whereas the outer-loop model dynamics is set to be relatively slow. The stability and convergence of the proposed control law is proved by Lyapunov theorem. One of the merits of the proposed reconfigurable controller is that the FDI process and the persistent input excitation are not necessary, which is suitable for the flight control system. To evaluate the reconfiguration performance of the proposed control method, numerical simulation is performed using six degree-of-freedom nonlinear dynamics.