• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.519-522
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• 2003

The purpose of this study is to analyze various hydraulic characteristics using SMS (Surface Water Modelling System) RMA2 model. It is based on 2-D finite element method. River reaches (13.8km) from Gyeongan gauge station to the inlet of Paldang lake was selected. Finite element was made by RIMGIS Data, and the analysis of river-changes was operated by unsteady flow. The sediment concentration and bed change was simulated using SED2D model.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.207-210
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• 2008

Recently many studys have been continued Nak-Dong river. This study recognized the importance about a rivers floor change. The Nak-Dong main river of railroad bridge(2.423Km) waegwan-eup, Cilgok-gun, Gyeongsangbuk-do analyzed to the SED2D-WES model. This study recognized the difference of the model according to the existence and nonexistence of the bridge piers. At a result of mean velocity current is higher in bridge option appeared in this case. As well sediment transportation model show that river bed change appear the part of velocity is low.

• Journal of Korea Water Resources Association
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• v.46 no.12
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• pp.1157-1167
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• 2013

Sayeon dam is the one that is structured in 1965 and supplying residential water in Ulsan. The hill located within the reservoir near the entrance of the dam spillway plays a role as a natural Dike. According to the recent surveys on change of sediment and effective volume of water kept in store, the latter that decreased 2.92% from twenty million tons and the former increased just 1.65 m. In this survey we examined the application of SED-2D model using measured data of Sayeon dam sediment. In addition we surveyed the inflow control and the water depth to be kept when installing small hydraulic structure similar to Dike around the dam reservoir entrance. To do this, we simulated the hydraulic effects and sediment on the conditions eliminating the hill or installing the structure higher than it. The controlling effects of present hill or adding small hydraulic structure on it was found, though the changes of the measure was not large.

• Journal of Korean Society of Disaster and Security
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• v.12 no.2
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• pp.35-45
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• 2019

The enlargement and reduction of river channels can not only change the flow of water but also alter sedimentation patterns, thus hindering smooth flood conveyance. Accordingly, this study aims to analyze the effects of the sudden enlargement of river channels on changes in the riverbed and river flow. For this purpose, as part of the "Hometown River" Construction Project, this study examined the local river Kyungpo-cheon, which a section of the river channel was widened by at least two- to three-fold, using RMA-2 and SED-2D models to simulate the changes in flow characteristics and riverbed variation due to the widening of the channel. The results of the study indicated that widening the Kyungpo -cheon river channel secured its dimensional stability in comparison to before widening. however, due to a flood frequency of more than once per year, future maintenance and management will be costly and time-consuming.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.908-911
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• 2004

The purpose of this study is to investigate the applicability of the two dimensional model in natural rivers. In this study, two dimensional unite element model, SMS, is used to simulate a complex flow along with the sediment movements in the natural river. The RMA-2 model embeded in SMS is used to simulate flow phenomena and SED-2D model is employed to simulate sediment transport. The model is applied to the confluence zone of the Gam River and mouth of Nakdong River. For model calibration, the result of the unsteady flow analysis is compared with the Typhoon 'Rusa' data. In addition, the runoff analysis was conducted for the determination of the project flood and the flood forecasting. The simulation results presented the characteristics of two dimensional flow with velocity vector and flow depth. The sediment transport characteristics are shown in terms of sediment concentration as well as bed elevation change. Accordingly, the SMS model in this study turned out to be very effective tool for the simulation of the hydrodynamic characteristics under the various flow conditions and corresponding sediment transports in natural rivers.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.42.2-42.2
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• 2020

We report on multi-wavelength observations of AA Ori, a Young Stellar Object in Orion-A star-forming region. AA Ori is known to have a pre-transitional disk based on infrared observations including Spitzer/IRS data. We construct its broadband spectral energy distribution (SED) by not only taking data in the optical and IR region but also including Herschel/PACS, JCMT/SCUBA, and SMA observational data. We use the Monte Carlo radiative transfer code (RADMC-3D) to reconstruct the SED with a viscous accretion disk model initialized by a radially continuous disk and finally having an inner and outer dusty disk separated by a dust-depleted radial gap. By comparing the model SEDs with different configurations of disk parameters, we discuss the limits to find a single solution of model parameters to fit the data. We suggest that some models with a modified inner disk surface density gradient and some degree of dust depletion in the inner disk can explain the AA Ori's SED, from which we infer that the inner disk of AA Ori has evolved. We present that model configurations of a pre-transitional disk with a large gap extended to 60-80 AU in a settled dusty disk of a few hundred AU size with a high inclination angle (~60°) also create model SEDs close to the observed one. To distinguish whether the disk has a just-opened narrow gap or a large gap, with an altered surface density of the inner disk extended to 10 AU, we suggest a further investigation of AA Ori with high angular resolution observations.

• Journal of Life Science
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• v.33 no.3
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• pp.242-251
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• 2023

The purpose of this study was to investigate the effects of 8-week β-hydroxybutyrate (β-HB) administration with and without endurance exercise training on endurance exercise performance and skeletal muscle protein synthesis and degradation using a mouse model. Forty-eight male wild-type ICR mice (8 weeks old) were randomly divided into four groups: sedentary control (Sed+Con), (Sed+Con), sedentary β-HB (Sed+β-HB), exercise control (Exe+Con), and exercise β-HB (Exe+β-HB). β-HB was dissolved in PBS (150 mg/ml) and injected subcutaneously daily (250 mg/kg) for 8 weeks. Mice performed 5 days/week of a 20 min treadmill running exercise for 8 weeks. The running exercise was carried out at a speed of 10 m/min at a 10° incline for 5 min, and then the speed was increased by 1 m/min for every 1 min of the remaining 15 min. Following 8 weeks of treatments, visceral fat mass and skeletal muscle mass, blood parameters, and the markers for autophagy and protein synthesis were analyzed. The data were analyzed with one-way ANOVA (p<0.05) using the SPSS 21 program. Eight weeks of Exe+β-HB treatment significantly lowered blood lactate levels compared with the other three groups (Sed+Con, Sed+β-HB, and Exe+β-HB) Exe+β-HB) (p<0.05). Eight weeks of Exe+β-HB significantly increased maximal running time (time to exhaustion) compared with the Sed+Con and Exe+Con groups (p<0.05). Eight weeks of β-HB administration significantly decreased autophagy flux and autophagy-related proteins in the skeletal muscle of mice (p<0.05). Conversely, the combined treatment of β-HB and endurance exercise training increased protein synthesis (mTOR signaling and translation) (p<0.05). The 8-week β-HB treatment and endurance exercise training had synergistic effects on the increase in endurance performance, increase in protein synthesis, and decrease in protein degradation in the skeletal muscle of mice.

• Journal of the Korean Society of Hazard Mitigation
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• v.6 no.1 s.20
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• pp.69-81
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• 2006

The purpose of this study is to identify the downstream influences due to the dam discharge by using 2-dimensional model, SMS(Surface water Modeling System). RMA-2 and SED-2D in SMS were applied to Yongdam multipurpose dam watershed located in Gum river basin. Through the simulation, erosion and deposit quantitative analysis of sinuous channels and scour pattern analysis of bridges have been done. A differences erosion depths between deposit are simulated as $-102.4 mm{\sim}54.2 mm$ at No.176(1.4 km) and $-104.1 mm{\sim}28.9 mm$ at No.146(7.4 km), sinuous channel. The river bed at Kamdong bridge in straight channal is simulated as uniform erosion. However, the river bed at Dumdul bridge in sinuous channal has been shown as different erosion depths at each sides. Consequently, the parts that could not be simulated on the existing 1-dimensional model, can be improved results by using a 2-dimensional model, about weakness points for hydraulic modeling such as extreme bend, tributary confluence.

• The Journal of the Acoustical Society of Korea
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• v.40 no.2
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• pp.139-147
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• 2021

This paper introduces and implements a Sound Event Detection (SED) system based on weakly-supervised learning where only part of the data is labeled, and analyzes the effect of parameters. The SED system estimates the classes and onset/offset times of events in the acoustic signal. In order to train the model, all information on the event class and onset/offset times must be provided. Unfortunately, the onset/offset times are hard to be labeled exactly. Therefore, in the weakly-supervised task, the SED model is trained by "strongly labeled data" including the event class and activations, "weakly labeled data" including the event class, and "unlabeled data" without any label. Recently, the SED systems using the mean-teacher model are widely used for the task with several parameters. These parameters should be chosen carefully because they may affect the performance. In this paper, performance analysis was performed on parameters, such as the feature, moving average parameter, weight of the consistency cost function, ramp-up length, and maximum learning rate, using the data of DCASE 2020 Task 4. Effects and the optimal values of the parameters were discussed.

• Korean Journal of Exercise Nutrition
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• v.23 no.3
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• pp.45-49
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• 2019

[Purpose] Recent studies suggest that ursolic acid (UA) is a potential candidate for a resistance exercise mimetic that can increase muscle mass and alleviate the deleterious effect of skeletal muscle atrophy on bone health. However, these studies evaluated the effects of UA on skeletal muscle and bone tissues, and they have not verified whether such effect could occur concurrently on muscle and bone, as is the case with resistance exercise. Thus, the aim of this study was to analyze the effect of UA injection on muscle mass and bone microstructure using an animal model of atrophy to demonstrate the potential of UA as a resistance exercise mimetic. [Methods] The immobilization (IM) method was used on the left hindlimb of Sprague Dawley (SD) rats for 10 days to induce muscle atrophy, whereas the right hindlimb was used as an internal control (IC). The animal models were divided into two groups, SED (sedentary, n=6) and UA (n=6) to demonstrate the effect of UA on atrophic skeletal muscles. The UA group received a daily intraperitoneal injection of UA (5 mg/kg/day) for 8 weeks. After 10 days of IM, the data collected for the IC were compared with that of IM to determine whether muscle atrophy might occur. [Results] Muscle atrophy was induced and bone mineral density (BMD) decreased significantly. The 8-week UA treatment significantly increased the gastrocnemius muscle mass compared to the SED group. In regard to the effect of UA on bones, negative results such as a decrease in BMD, trabecular bone volume fraction, and trabecular number, and an increase in trabecular separation, were observed in the SED group, but no such difference was observed in the UA group. No significant difference was observed in atrophic hindlimbs between SED and UA groups. [Conclusion] These results alone are insufficient to suggest that UA is a potential resistance exercise mimetic for atrophic skeletal muscle and weakened bone. However, this study will help determine the potential of UA as a resistance exercise mimetic.