• Korean Journal of Remote Sensing
• /
• v.25 no.5
• /
• pp.445-454
• /
• 2009

Localized unprecedented torrential rain and heavy rainfall cause repeated damages and make it difficult to detect and predict the landslide caused by heavy rainfall. To analyze the landslide characteristics of Inje area this study used satellite images photographed after the occurrence of landslide caused by the typhoon Ewiniar occurred in July, 2006, and for GIS analysis purpose, interpreted the satellite images (SPOT5) visually to digitize into developing parts, water traveling parts and sediment parts. For analysis of spatial characteristics, landslide areas obtained from visual interpretation of digital map, 3rd & 4th forest vegetation maps and detailed soil map and grids were overlaid and analyzed. As a result, in regard to topographic features, landslide occurred at places, of which average slope is $26.34^{\circ}$, had south, south-east, south-west aspects and average altitude of 627m. From hydrological analysis, it was found out that water traveling area rapidly spread approaching water traveling area and sediment area. From forest type analysis, it was found out that landslide occurrence was high in pine woods, and in terms of girth class attribute, landslide occurred in small-sized woods, in which the crown occupancy of trees that have the diameter at breast height, 6~16cm, was greater than 50%. From the analysis of soil series, landslide areas constitute 37.85% of OdF and 37.35% of SmF, which had sandy loam soil and excellent drainage capacity. Through this study, landslides in Inje area were characterized and SPOT5 images of 2.5m resolution could be used. But there was a difficulty in determining water traveling parts adjacent to urban area.

• Journal of the Korean Applied Science and Technology
• /
• v.34 no.3
• /
• pp.451-460
• /
• 2017

This study optimized the extraction of antioxidants from Gugija (Lycium chinensis Mill). To determine operational parameters, including ethanol concentration ($X_1$, 0~80%) and extraction time ($X_2$, 1~5 hr), response surface methodology was applied to monitor yield, anthocyanins, flavonoids and DPPH radical scavenging activity. Coefficients of determinations ($R^2$) of the models were range of 0.8645~0.9859 (p<0.01~0.1) in dependant parameters. Yield of Gugija extracts was maximized 23.12% in extraction conditions of 4.22 h at 8.25% ethanol. Anthocyanins was maximized 1.43 (OD in 530 nm) in extraction conditions of 3.06 h at 79.98% ethanol. Flavonoids was maximized $3,100{\mu}g/100g$ in extraction conditions of 3.37 h at 67.02% ethanol. DPPH radical scavenging activity was maximized 96.93% in extraction conditions of 1.67 h at 69.81% ethanol. Optimum extraction conditions (2.5 h extraction at 70% ethanol) were obtained by superimposing the contour maps with regard to anthocyanins, flavonoids and DPPH radical scavenging activity of Gugija. Maximum values of anthocyanins, flavonoids and DPPH radical scavenging activity in optimum extraction condition were 1.0080 (OD in 530 nm), $3,145{\mu}g/100g$, 96.96%, respectively. But values of anthocyanins, flavonoids and DPPH radical scavenging activity in water extraction condition (1 h at water) were 0.4652 (OD in 530 nm), $1,633{\mu}g/100g$, 86.98%, respectively.

• Journal of the Korean Chemical Society
• /
• v.41 no.11
• /
• pp.594-599
• /
• 1997

Lithium nickel oxide ($Li_{2x}Ni_{1-x}O$) thin films have been prepared by the RF sputtering of lithiated nickel oxide target, where the film microstructure was controlled by the sputtering atmosphere $(Ar/O_2)$ and the substrate temperature ($T_s=50/230^{\circ}C$). From the transmission electron microscopic analysis, it is found that the most porous film with the grain size of $∼80\AA$ could be fabricated under the sputtering atmosphere of $P(O_2)=8{\times}10^2$ mbar with the $$T_s$=50^{\circ}C.$ In the optical and electrochemical studies, the$Li_{2x}Ni_{1-x}O$ films exhibit a significant electrochromic property in association with the lithium insertion/deinsertion process. The amount of charge insertion ($Q_i$) and the optical density (OD) variation depend on the crystallinity of the film as well as its thickness, and for the $Li_{2x}Ni_{1-x}O$ film (170 nm thickness) prepared under $O_2$ atmosphere and $T_s=50^{\circ}C$, the OD could be increased up to ∼1.3 by the charge insertion with $Q_i=30\;mC/cm^2.$

• Journal of Korean Society of Transportation
• /
• v.26 no.4
• /
• pp.205-215
• /
• 2008

As static traffic assignment has reached its limitation with ITS policy applications and due to the increase of interest in studies of ITS policies since the late 1980's, dynamic traffic assignment has been considered a tool to overcome such limitations. This study used the Dynameq program, which simulates route choice behavior by macroscopic modeling and dynamic network loading and traffic flow by microscopic modeling in consideration of the feasibility of the analysis of practical traffic policy. The essence of this study is to evaluate the feasibility for analysis in practical transportation policy of using the dynamic traffic assignment technique. The study involves the verification of the values estimated from the dynamic traffic assignment with South Korea's expressway network and dynamic O/D data by comparing results with observed link traffic volumes. This study used dynamic O/D data between each toll booth, which can be accurately obtained from the highway Toll Collection System. Then, as an example of its application, exclusive bus-lane policies were analyzed with the dynamic traffic assignment model while considering hourly variations.

• Journal of Korea Port Economic Association
• /
• v.34 no.3
• /
• pp.93-112
• /
• 2018

The purpose of this study is to analyze the flow of e-commerce freight transported by maritime transportation for China and to identify the characteristics of cargo by region/item for finding the ways to promote e-commerce export to China. Thus, this study analyzed the e-commerce export and import data on cargo moved via maritime transportation between Korea and China from 2015 to 1Q18, using Origin-Destination(OD) analysis and visualization techniques. The results indicated that the largest number of Chinese e-commerce cargoes were imported at Incheon Port, which has a clearance facility for e-commerce cargo. In the case of Pyeongtaek Port, e-commerce cargo imported from China has transported to Incheon Customs again, causing the inefficiency through the customs clearance process. Unlike the case of e-commerce imports where the final destination is distributed nationwide, e-commerce products exported to China through maritime transportation were found to be mainly confined to Seoul and Gyeonggi provinces, where freight forwarding companies and forwarders are concentrated. In addition, unlike e-commerce import cargoes, e-commerce items exported through maritime transportation were mainly confined to clothing and cosmetics, and export volume was also less than imports. This study provides some possible strategies to increase the volume of freight and to attract export products as follows: i) to diversify products exported to China through e-commerce transshipment, ii) to diversify export items by building the cold chain in e-commerce transport with China.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.7
• /
• pp.4580-4587
• /
• 2014

This study provides an improved transportation mode choice models applicable to the Busan-Ulsan Metropolitan area by scrutinizing previous study results developed using the multinomial logit model. Although the previous model has an appropriate modeling structure in terms of the sign of coefficient estimates and goodness-of-fit, the model ignores the total number of trips and traffic congestion condition between the two zones and partially reflects zone-specific variables and choice set. Therefore, this study considered all of these modeling faults by re-constructing the representative utility functions. The modeling results show that travelers in Busan-Ulsan metropolitan area tend to choose their mode using mode-specific characteristics rather than the classical travel time and/or cost variables.

• Journal of Korean Society of Transportation
• /
• v.33 no.3
• /
• pp.304-314
• /
• 2015

Detour of metro (subway) in metropolitan area has been regarded as one of inherent elements that make entire metro system less competitive than passenger cars. However, factors affecting detour of metro line is not specified clearly when a new subway system is planned or an existing system is improved. Previous detour-related studies was reviewed for developing 'distance efficeincy evaluation model' for metro as well as its counterpart (i.e. road). Metro line 3 (orange line) of Seoul metropolitan area was applied as a case study. As a results, the most detoured OD segment is Daechi - Apgujeong and its detour factor is 1.93 which means that the distance of the metro is 1.93 times longer distance compared to the distance of the road. The metro line 3 has averagely 20% longer distance compared to road for the identical O/D pairs.

• Microbiology and Biotechnology Letters
• /
• v.39 no.2
• /
• pp.182-187
• /
• 2011

In this study, A bacterium with an ability to resist toxic heavy metals was isolated from reeds in wetland. The isolated strain was identified to Alcaligenes sp. KC-1 by 16S rDNA sequencing. Heavy metals such as Pb, $Cr^{6+}$, Cd, Zn and Cu were supplied to media. The ecotoxic treat of the heavy metals on the growth of strain KC-1 was performed when the isolated strain Alcaligenes sp. KC-1 cultured with Cu ranging from 0 mM to 20 mM. It showed the resistance of $EC_{50}$(7.34 mM) and cell growth ($OD_{600\;nm}$ : 0.83 after 42 hours) when it was cultured in Cu.

• Journal of the Korean Society for Railway
• /
• v.12 no.3
• /
• pp.348-356
• /
• 2009

The objective of this paper is to estimate the DMT utility function for the transportation mode choice using SP survey. With the freight OD data the estimated utility function can be used as a basic data for forecasting DMT market. 3 alternatives of transportation mode are considered in SP survey; railway, road and DMT. The utility functions are developed according to the freight items, which are container, steel and chemical product. In this study the attribute variable are chosen as time, cost and reliability. The number of level for attribute variables are 3. The high valve is determined as +10% above the standard and the low value -20% below the standard.

• Journal of Korean Clinical Health Science
• /
• v.7 no.2
• /
• pp.1337-1344
• /
• 2019

Purpose. This study was the analyze the refractive status of presbyopia in Korea. Methods. The subjects was from November 2018 to October 2019, two hundred thirty four subjects( 117 male subjects, 117 female subjects; from 40-year old to 88-year old ) were performed in refraction test using the Auto-Refraction(Speed -K model, Japan). The myopia, hyperopia, astigmatism, and anisometropia were defined as spherical equivalent(SE)≤-0.50 diopters, SE ≥+1.00 D, cylinder error ≥0.75 D and SE difference≥1.00 D between binocular eyes, respectively. Results. The refractive status by spherical equivalent among all subjects was myopia 61.43%, astigmatism 86.86%, emmetropia 19.18%, anisometropia 12.07%, and hyperopia 18.54. The prevalence of myopia and astigmatism were much more common in male. However, The hyperopia and astigmatism were much more common in female. The prevalence of spherical equivalent was much common from -0.50 diopter to -5.00 diopter. On the other hand, the prevalence of astigmatism and myopia was much more than hyperopia in all subjects. There was a statistical significance between OD and OS of the female and male in the spherical equivalent power(p<.000). However, there was not statical significant between female and male of OD and OS in the spherical equivalent power(p<.070). On the other hand, The prevalence of againest axis in astigmatism was more common in all subjects. In ADD power for the near vision correction, the female was much more diopter than male. Conclusions. These results suggested that the analysis of the refractive status on the presbyopia in Korea can give the useful diagnosis data for the correction of visual acuity at near distance.