• Korean Journal of Environment and Ecology
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• v.23 no.1
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• pp.50-55
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• 2009

To understand the status of the migrating Oriental Honey Buzzard(Pernis ptilorhynchus) in Korea, we carried out a preliminary study on the number and local movements of the Honey Buzzard from September 2005 to October 2007 at Hongdo Island, Jeonnam Province, Korea. A total of 702 Honey Buzzards in 2005, 404 individuals in 2006, and 659 individuals in 2007 were recorded during the fall migration season, but during the spring migration season only two and eight birds were observed in 2006 and 2007 respectively. The migrating Honey Buzzard showed peak numbers from 20 September to 5 October at the study site. According to observation of arrival time of538 Honey Buzzard in October 2007, a total of 2l6 birds(40.l %) were passing over Hongdo Island between 7:00 AM to 8:00 AM, rising skyward on columns of warm air. This suggests the use of thermal currents and avoidance of nocturnal movement for crossing water. They preferred moderate winds(<5 m/s in speed) from northwest, but the migrating number apparently decreased in case of strong winds (${\geqq}5 m/s$). This suggests that wind speed and direction are important environmental factors for migration of the Oriental Honey Buzzard. At present, it is unclear which breeding population(from north-eastern China or Japan) passes over Hongdo Island. Moreover, it is difficult to prove migration route and to understand migratory behaviors of the Oriental Honey Buzzard in Korea. To prove the breeding sites and routes of the migrants over the study site, we need more detailed and further studies such as satellite tracking researches.

• Journal of Ginseng Research
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• v.39 no.2
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• pp.116-124
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• 2015

Background: Ginseng, the root of Panax ginseng (PG), is used widely as a herbal medicine to prevent and treat various diseases. Panax ginseng has pharmacological effects on neurodegenerative diseases such as Alzheimer's disease (AD). The present study evaluated the neuroprotective effects of PG and its possible neuroprotective mechanisms in advanced glycation end product (AGE)-induced AD in a rat model. Methods: Advanced glycation end products were injected bilaterally into the CA3 region of the rats' brains. The Morris water maze test and step-down type passive avoidance test were performed to evaluate their memory and cognitive abilities. The oxidation indexes in the hippocampus were detected. Immunohistochemistry was conducted to visualize the receptors for advanced glycation end products (RAGEs) and nuclear factor-kappa-light-chain-enhancer of activated B cell (NF-${\kappa}B$). Results: Behavioral results showed that PG (1 g/kg, 0.5 g/kg, and 0.25 g/kg) significantly shortened the escape latency, remarkably increased the number of crossing times, significantly decreased the number of errors, and prolonged the latency in rats with AGE-induced AD. Panax ginseng also significantly reduced the malondialdehyde level, increased the glutathione content, and increased superoxide dismutase activity in the hippocampus. Panax ginseng significantly decreased the expression of RAGE and NF-${\kappa}B$. The blockade of anti-RAGE antibody could significantly reduce AGE-induced impairments and regulate these expressions. Conclusion: Our results demonstrated that PG significantly inhibits AGE-induced memory impairment and attenuates Alzheimer-like pathophysiological changes. These neuroprotective effects of PG may be associated with the RAGE/NF-${\kappa}B$ pathway. Our results provided the experimental basis for applying PG in preventing and treating AD.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.6
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• pp.53-66
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• 2017

In order to improve traffic flow and vehicular safety, installation of roundabouts is encouraging recently. Roundabouts are generally installed at which traffic flow and pedestrian flow is relatively low intersections. Roundabouts reduce vehicle speed, minimize vehicle weaving, and reduce critical conflict points. For these reasons, roundabouts are generally operated unprotected pedestrian crosswalk, thus a shortcoming for pedestrian safety always exists at roundabouts. The purpose of this study is developing a dynamic signal metering algorithm for traffic and pedestrian at four-way-approach with two-lane roundabouts in which three different operation algorithms(fixed-time pedestrian, vehicle signal metering, and vehicle and pedestrian signal metering) are suggested and its performance is tested by using VISSIM. The results of the fixed pedestrian signal operation show that there is a big average delay increase in general and that increases up to 51.4 seconds/vehicle(42.5%) when the total number of approaching vehicle is 3,800 vehicle/hour. However, the results of the simultaneous dynamic signal metering operation for the vehicle and pedestrian crossing with push button show that there is a substantial average delay reduction up to 40.6 seconds/vehicle(42.7%) when the total number of approaching vehicle is 3,000 vehicle/hour.

• Korean Journal of Plant Resources
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• v.25 no.1
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• pp.152-155
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• 2012

A new Saxifraga fortunei 'Pinkle' was bred by crossing 'Juno' with 'Hongoan', both with light pink (RP-N66A)-colored petals. The selection of promising lines and characterization of flowers were conducted from 2004 to 2008 year in greenhouses of the Highland Agriculture Research Center, NICS, RDA. The flowering of 'Pinkle' starts on October 7 and lasted for 27 days. The number of flowers per plant is 99.7 with many flowering habits. The flower show mixed dark pink (R-P N66C) colors at opening. The flower have 5.0 petals, each have the size is 2.9 cm in width and 3.2 cm in length. Mean plant height is 15.8 cm and number of leaves are 44.3 ea. 'Pinkle' can be used as a pot flower. Fifty percent shading of the sunlight is recommended and soft rot disease occurs caused by over-irrigation. 'Pinkle' was registered as a new cultivar in Korea Seed and Variety Service in April 2011.

• Journal of Animal Science and Technology
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• v.57 no.2
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• pp.5.1-5.8
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• 2015

Background: Korean native chicken (KNC) is a well-known breed due to its superior meat taste. This breed, however, owing to a low growth rate, has a high market price. In order to overcome this disadvantage, the National Institute of Animal Science (NIAS) in Korea developed a commercial KNC breed, named Woorimatdag version 2 (WM2), an upgraded version of the Woorimatdag (WM1) breed and the WM2 was created by crossing the KNC with meat type breeds. This study aims to discriminate between WM2 and other chicken breeds using microsatellite (MS) markers. Methods: A total of 302 individuals from eight Korean chicken populations were examined. The genetic diversity and population structure analysis were investigated using Cervus, API-CALC, STRUCTURE, PowerMarker programs. Results: Based on heterozygosity and polymorphic information content (PIC) values, 30 MS markers were initially selected from 150 markers. The identified average number of alleles (Na), expected heterozygosity, and PIC values for the WM2 samples were 7.17, 0.741, and 0.682, respectively. Additionally, the paternity of individuals was assigned with a success rate of greater than 99% using 12 markers, the best minimum number of markers. The 12 selected markers contained heterozygosity and PIC values above 0.7 and probability of identity values around zero. Using these markers, the determined probability of identity (PI), $PI_{half-sibs}$, and $PI_{sibs}$ values were 3.23E-33, 5.03E-22, and 8.61E-08, respectively. Conclusions: WM2 is well differentiated with respect to other chicken breeds based on estimated genetic distances. The results presented here will contribute to the identification of commercial WM2 chicken in the market.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.156-156
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• 2000

Recently, the surface electronic states have attracted much attention since their standing wave patterns created around steps, defects, and adsorbates on noble metal surfaces such as Au(111), Ag(110), and Cu(111) were observed by scanning tunneling microscopy (STM). As a typical example, a striking circular pattern of "Quantum corral" observed by Crommie, Lutz, and Eigler, covers a number of text books of quantum mechanics, demonstrating a wavy nature of electrons. After the discoveries, similar standing waves patterns have been observed on other metal and demiconductor surfaces and even on a side polane of nano-tubes. With an expectation that the surface states could be utilized as one of ideal cases for studying two dimensionakl (sD) electronic system, various properties, such as mean free path / life time of the electronic states, have been characterized based on an analysis of standing wave patterns, . for the 2D electron system, electron density is one of the most importnat parameters which determines the properties on it. One advantage of conventional 2D electron system, such as the ones realized at AlGaAs/GaAs and SiO2/Si interfaces, is their controllability of the electrondensity. It can be changed and controlled by a factor of orders through an application of voltage on the gate electrode. On the other hand, changing the leectron density of the surface-state 2D electron system is not simple. On ewqy to change the electron density of the surface-state 2D electron system is not simple. One way to change the electron density is to deposit other elements on the system. it has been known that Pd(111) surface has unoccupied surface states whose energy level is just above Fermi level. Recently, we found that by depositing Pd on Cu(111) surface, occupied surface states of Cu(111) is lifted up, crossing at Fermi level around 2ML, and approaches to the intrinsic Pd surface states with a increase in thickness. Electron density occupied in the states is thus gradually reduced by Pd deposition. Park et al. also observed a change in Fermi wave number of the surface states of Cu(111) by deposition of Xe layer on it, which suggests another possible way of changing electron density. In this talk, after a brief review of recent progress in a study of standing weaves by STM, I will discuss about how the electron density can be changed and controlled and feasibility of using the surface states for a study of 2D electron system. One of the most important advantage of the surface-state 2D electron system is that one can directly and easily access to the system with a high spatial resolution by STM/AFM.y STM/AFM.

• Journal of Korea Water Resources Association
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• v.44 no.1
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• pp.65-72
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• 2011

Natural streams meander, forming pools at the outer part of bend and riffles at the crossing. Pools are deep at a lower flow velocity, and riffles are shallow at a higher flow velocity. Attentions are being paid to pool-riffle sequences in meandering streams because pool-riffle sequences tend to increase biodiversity of the stream ecosystem. This study investigates the characteristics of distribution of bed sediment particles in the upstream reach of the Gap Stream, which is a tributary of the Geum River in Korea. The upstream part of the Gap Stream, the study reach, is a gravel-bed stream, showing a pool and three riffles due to meandering. The reach also includes pools at the upstream and downstream parts of the weir. The characteristics of bed sediment particles sampled at the wetland and in the side channel are studied, revealing that the median particle diameter in the riffle is about four times larger than that in the pool. In addition, flow simulations are carried out for ordinary discharge and design flood, and such parameters important to sediment transport as velocity, shear stress, dimensionless shear stress (or Shields number), and dimensionless shear velocity are provided to see the mobility of sediment particles in the pool-riffle sequence.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.775-782
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• 2021

The Myodo-Strait at Yeosu Port is normally used as a major vessel passage for dangerous cargo carriers that carry regular products of dangerous goods. Currently, the Myodo-Strait allows only single passage, and the speed of passage is also limited to 8 knots. As a result, demurrage at the wharf of hazardous goods are also on the rise. It is expected that the development of a number of dangerous commodity wharf in the future will increase the volume of vessel traffic and increase the number of vessels used in the project area. Therefore, it is urgent to improve the waterway in order to secure the safety of ships using the waterway and improve the demurrage. This study proposed an improvement plan for the waterway through the analysis of the marine environment of the waterway and the process of collecting opinions from users in the sea area. and it was finally proposed to expend the width of the strait to 300m and secure a depth of 9.50m through Guidelines of Port and Harbor Design review and ship handling simulation evaluation. In addition it was evaluated that the vessel traffic congestions at peak-time in the situation of solo passage was greatly improved from 71.01% to 47.3% even when it was allowed to ship's crossing passage, as a result of vessel traffic congestions evaluation. According to the proposed improvement plan, the safety of ships' passage in the project area can be secured, and the issue of demurrage was also considered to be improved.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.2
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• pp.195-206
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• 2023

Most of the Micro-mobility parking in Korea use Dockless system. However, Dockless can result in cluttering, infrastructure deficiencies, and safety challenges as has been observed in cities. It is necessary to introduce a Station Parking system in order to solve the drawbacks of the dockless, but the introduction without engineering has low accessibility and induces side effects. In this study, to decide optimal location about number of the Micro-mobility Station, we has been applied the MCLP model about the coverage range, usage demand, usage time in order to classify the type of Micro-mobility Station. For the MCLP, User Date input to reflect realistic demand in Bundang new town, Korea. The result show that the optimal number of facilities in 400 m was 146, and the coverage ratio was 99.83 %, which was most suitable coverage for solving the parking problem. We also classified the demand into 4 levels and the usage time into 3 levels, and by crossing them, we were able to classify the Parking lot types into 12 types. It is possible to propose strategic policies in the installation and operation of Micro-mobility Parking System.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.5
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• pp.265-277
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• 2019

Using the measured data of waves and shore-line, we reviewed the grand circulation process and seasonal variation of beach cusp at the Mang-Bang beach from the perspective of trapped mode Edge waves known as the driving mechanism of beach cusp. In order to track the temporal and spatial variation trends of beach cusp, we quantify the beach cusp in terms of its wave length and amplitude detected by threshold crossing method. In doing so, we also utilize the spectral analysis method and its associated spectral mean sand wave number. From repeated period of convergence and ensuing splitting of sand waves detected from the yearly time series of spectral mean sand wave number of beach cusp, it is shown that the grand circulation process of beach cusp at Mang-Bang beach are occurring twice from 2017. 4. 26 to 2018. 4. 20. For the case of beach area, it increased by $14,142m^2$ during this period, and the shore-line advanced by 18 m at the northen and southern parts of the Mang-Bang beach whereas the shore-line advanced by 2.4 m at the central parts of Mang-Bang beach. It is also worthy of note that the beach area rapidly increased by $30,345m^2$ from 2017.11.26. to 2017.12.22. which can be attributed to the nature of coming waves. During this period, mild swells of long period were prevailing, and their angle of attack were next to zero. These characteristics of waves imply that the main transport mode of sediment would be the cross-shore. Considering the facts that self-healing capacity of natural beaches is realized via the cross-shore sediment once temporarily eroded. it can be easily deduced that the sediment carried by the boundary layer streaming toward the shore under mild swells which normally incident toward the Mang-Bang beach makes the beach area rapidly increase from 2017.11.26. to 2017.12.22.