• Journal of Korean Society of Transportation
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• v.31 no.3
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• pp.86-95
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• 2013

In this study, a model of compensation and amendment of forecasted travel demand was developed to calculate the range of values depends on the changes in the risk factors, selecting factors that might affect traffic demand changes among risk factors. Selected factors are as follows: influenced area population, the number of registrated vehicle per person, ratio of service industry workers, and city intervals. Then this model is applied to six routes of expressway and the calculated value were compensated with error rate being reflected on each quartile value with respect to influenced area population (200,000 people standards). Result from appling developed model to Cheongwon-Sangju expressway suggests that the model could compensate the error rate by more than 50%, which in turn validate the effectiveness of the model developed. Some limitations and future research agenda have also been identified.

• Toxicological Research
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• v.8 no.2
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• pp.273-284
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• 1992

It is well known that phenytoin (PHT), a commonly prescribed anticonvulsant, has teratogenicity in experimental animals and human. The major malformation induced by PHT in mouse is cleft palate. The mechanisms of the embryotoxic effects of PHT are unknown. However, PHT and synthetic glucocorticoids share several features with respect to their teratogenicity, and it was known that PHT increased maternal corticosterone level. Therefore PHT-induced cleft palate may be mediated indirectly by elevated maternal corticosterone. Recently it was reported that secalonic acid Dinduced cleft palate and elevated endogenous corticosterone level, and that such effects were antagonized by DMSO. The purpose of this work was to investigate whether the elevated maternal corticosterone is associated with the teratogenicity of PHT in the ICR mouse fetuses by treatment with PHT or PHT plus DMSO. PHT (74mg/kg, BW) was daily administered intraperitoneally on day 10~12 of gestation with and without DMSO(2ml/kg, BW), and the fetal malformation was observed on day 18. Maternal serum corticosterone and fetal PHT levels were determined by HPLC. The results are summarized as follows. 1)The percentage of cleft palate incidense in fetuses following treatment with PHT on day 10~12 of gestation was 51.7%. 2)There was a significant decrement in the cleft palate incidence in fetuses to 30.8% in the group treated with PHT plus DMSO compared with 51.7% in that with PHT alone. 3) Maternal serum corticosterone levels following treatment with PHT on day 10~12 of gestation increased by 116~343% compared with that of vehicle control. Such effect was antagonized by DMSO. 4)PHT concentration in the fetuses was not affected by DMSO. These results suggest that PHT-induced cleft-palate in fetuses seems to be closely associated with the elevation of maternal corticosterone level.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.4
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• pp.317-325
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• 2020

UAV (Unmanned Aerial Vehicle) photogrammetry has recently emerged as a means of obtaining highly precise and rapid spatial information due to its cost-effectiveness and high efficiency. However, current procedures or regulations for quantitative quality verification methods and certification processes for UAV-images are insufficient. In addition, the current verification method for image quality is not evaluated by an MTF (Modulation Transfer Function) analysis or edge response analysis, which can analyze the degree of contrast including image resolution, and only relies on the GSD (Ground Sample Distance) analysis. Therefore, in this study, the edge response analysis using a Slanted edge target was performed along with GSD analysis to confirm the necessity of analyzing edge response analysis in UAV-images quality analysis. Furthermore, a Matlab GUI-based software tool was developed to help streamline the edge response analysis. As a result, we confirmed the need for edge response analysis since the outputs of the edge response analysis from the same GSD had significantly different outcomes. Additionally, we found that the quality of the edge response analysis of UAV-images is proportional to the performance of the camera mounted on the UAV.

• Journal of Life Science
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• v.15 no.3 s.70
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• pp.387-396
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• 2005

The aims of the study were to establish a short-term screening test for detecting testicular toxicity of chemicals in rats and to determine whether a 2-week administration period is sufficient to detect testicular toxicity of 2-bromopropane (2-BP) as an example. Male Sprague-Dawley rats were subcutaneously administered with 1000 mg/kg/day of 2-BP or its vehicle for 2 weeks. Ten male rats each were sacrificed on days 3, 7 and 14 after the initiation of treatment. Parameters of testicular toxicity included genital organ weights, testicular sperm head counts, epididymal sperm counts, motility and morphology, and qualitative and quantitative histopathologic examinations. The early histopathological changes observed on day 3 of treatment included degeneration of spermatogonia and spermatocytes, multinuclear giant cells, mature spermatid retention, vacuolization of Sertoli cells, and decreased number of spermatogonia in stages II and V. On day 7 of treatment, atrophy of seminiferous tubules, exfoliation of germ cells, degeneration of spermatogonia and spermatocytes, multinuclear giant cells, mature spermatid retention, vacuolization of Sertoli cells, decreased number of spermatogonia in stages II and V, and decreased number of spermatocytes in stages VII and XII. On day 14 after treatment, a significant decrease in the weights of testes and seminal vesicles was found. Atrophy of seminiferous tubules, exfoliation of germ cells, degeneration of spermatogonia and spermatocytes, mature spermatid retention, vacuolization of Sertoli cells, decreased number of spermatogonia in stages II and V, and decreased number of spermatocytes in all spermatogenic stages were also observed. In addition, a slight non-significant decrease in testicular sperm head counts, daily sperm production rate and epididymal sperm counts was found. The results showed that 2 weeks of treatment is sufficient to detect the adverse effects of 2-BP on male reproductive organs. It is considered that the short-term testicular toxicity study established in this study can be a useful tool for screening the testicular toxic potential of new drug candidates in rats.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.2
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• pp.98-106
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• 2011

The deck of steel box girder bridges is composed of deck plate, longitudinal rib, and transverse ribs. The orthotropic steel decks have high possibility to fatigue damage due to numbers of welded connection part, the heavy contact loadings, and the increase of repeated loadings. Generally, the local stress by the repeated loadings of heavy vehicles causes the orthotropic steel deck bridge to fatigue cracks. The increase of traffic volume and heavy vehicle loadings are promoted the possibility of fatigue cracks. Thus, it is important to exactly evaluate the structural behavior of bridge considering the contact loading area of heavy vehicles and real load patterns of heavy trucks which have effects on the bridge. This study estimated the effect of contact area of design loads and real traffic vehicles through the finite element analysis considering the real loading conditions. The finite element analysis carried out 4 cases of loading patterns in the orthotropic steel deck bridge. Also, analysis estimated the influence of contact area of real truck loadings by the existence of diaphragm plate. The result of finite element analysis indicated that single tire loadings of real trucks occurred higher local stress than one of design loadings, and especially the deck plate got the most influence by the single tire loading. It was found that the diaphragm attachment at joint part of longitudinal ribs and transverse ribs had no effects on the improvement of structural performance against fatigue resistance in elastic analysis.

• Journal of the Korean Magnetics Society
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• v.25 no.6
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• pp.189-197
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• 2015

As enforced the regulation of fuel efficiency, the electrification of automotive components in internal combustion vehicle has been applied instead of hydraulic pressure. A typical example of such parts is the EPS (electric power steering), and it is applied to most automotive at present. In electric power steering system, the core component is motor. The reduction of cogging torque and torque ripple is required to improve steering feeling and reduce NVH (Noise Vibration Harshness) in EPS. Generally the skewed design of stator or rotor is applied in order to reduce cogging torque and torque ripple. This paper propose the design and analysis methodology of Brusheless PMSM (Permanent Magnet Synchronous Motor) which is applied to skewed stator. The proposed methodology is as follows: First Intial Design PMSM with skewed stator for EPS, Second Optimal design using RSM (Response surface method), Third Performance Analysis such as Phase Back EMF, Inductance, Load torque using FEA (Finite Element Method). Finally, the reliability of proposed design methodology will be verified through the experiments of prototype sample.

• Journal of Digital Convergence
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• v.14 no.6
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• pp.439-448
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• 2016

The population over 65 years old is 12.7% of total population in 2014 and Korea is going to be an aged society in the near future. The transportation vulnerable including the aged should be guaranteed in walking mobility under safe and comfortable environment for their socio-economic activities. For the era of fusion and convergence this paper investigated the characteristics of walking accidents related to the aged pedestrians and analyzed the aged-oriented walking factors with a reaction time and a walking speed at crosswalks in Yeosu. In the results, the crashes for the aged occur at 9.9% of total crashes and the fatalities of the aged are 40.3% of total fatalities in 2014. The 47.4% of the aged fatalities is also attributed to vehicle-to-pedestrian accidents. The 49.3% of all pedestrian fatalities occurs at the aged pedestrians with a very high proportion. The reaction time and walking speed for the aged were determined as the values located at the lower 15%-tile of the elderly physical ability. It is shown that the reaction time is 4.56 seconds and the walking speed is 0.76 m/s in the case of Yeosu. From two factors' standpoint, the walking environment at crosswalks in Yeosu is inappropriate for the aged.

• Journal of Ginseng Research
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• v.40 no.3
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• pp.260-268
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• 2016

Background: During the aging process, skin shows visible changes, characterized by a loss of elasticity and the appearance of wrinkles due to reduced collagen production and decreased elasticity of elastin fibers. Panax ginseng Meyer has been used as a traditional medicine for various diseases due to its wide range of biological activities including skin protective effects. Ginsenosides are the main components responsible for the biological activities of ginseng. However, the protective activities of an enzymatic preparation of red ginseng against human skin aging have not been investigated. Methods: The efficacy of an enzyme-treated powder complex of red ginseng (BG11001) in preventing human skin aging was evaluated by oral administration to 78 randomized individuals. All patients were requested to take three daily capsules containing either 750 mg of BG11001 or a placebo vehicle for 24 wk; at the end of the testing period, skin roughness, elasticity, and skin water content were measured. Results: BG11001 significantly reduced the average roughness of eye wrinkles and the Global Photo Damage Score compared with the placebo, although there were no significant differences in arithmetic roughness average between the groups. In addition, gross elasticity and net elasticity values increased, and transepidermal water loss level decreased, indicating improved skin elasticity and moisture content. Conclusion: In conclusion, enzyme-treated red ginseng extract significantly improved eye wrinkle roughness, skin elasticity, and moisture content. Moreover, enzyme-treated red ginseng extract would be useful substance as a bio-health skin care product.

• KIISE Transactions on Computing Practices
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• v.21 no.3
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• pp.223-238
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• 2015

Ramp metering is the most effective and direct method to control a vehicle entering the freeway. This paper proposed the new density-based ramp metering method. Existing methods that use the flow data had low reliability data and can have various problems. Also, when the ramp metering was operated by freeway congestion, the additional congestion and over-capacity can occur in the ramp. To solve this problem with the existing method, the proposed method used the density and acceleration data of the freeway and considered the ramp status. The developed strategy was tested on Trunk Highway 62 west bound (TH-62 WB) in Minnesota Twin-City and compared with Stratified Zone Metering(SZM), which had been operating in the Twin-City freeway. To constitute the experiment environment, the VISSIM simulator was used. The Traffic Information and Condition Analysis System (TICAS) was developed to control the PTV VISSIM simulator. The experiment condition was set between 2:00 PM and 7:00 PM, Oct 5th, 2014 during severe traffic congestion. The simulation results showed that total travel time was reduced by 20% for SZM. Thus, we solved the problem of ramp congestion and over-capacity.

• Journal of Wetlands Research
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• v.9 no.3
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• pp.35-42
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• 2007

The paved areas such as parking lots and roads are stormwater intensive landuses since they are impervious and have high pollutant mass emissions from vehicular activity. Vehicle emissions include different pollutants such as heavy metals, oil and grease, particulates from sources such as fuels, brake pad wear and tire wear. Especially, the released heavy metals can be easily absorbed on the surface area of small particulate materials because of its ionic strength. Therefore, by constructing the sedimental tank in structural BMPs as a pre-treatment facility, the particles and heavy metals both can be removed from the runoff at an instant. To understand the physico-chemical characteristics of sediments from sedimentation tank, one-year study at an infiltration trench and filtration system was conducted to quantify the metal mass absorbed on sediments with various particle sizes. The structural BMPs for this study are located in Yongin City, Kyunggido. The research results show that Cu, Zn and Pb are dominant metal compounds in the sediments. Also the metal concentrations are highest at the ranges of $425-850{\mu}m$ particle sizes. The results will provide the basic physico-chemical information of sediments to treat it as solid wastes and to determine the design criteria of sedimentation tank in structural BMPs.