• Journal of the Korean Association of Geographic Information Studies
• /
• v.21 no.2
• /
• pp.107-119
• /
• 2018

The slope monitoring systems which have been operating at home and abroad were investigated and then the real-time monitoring management system for evacuating inhabitants based on Web-EOC(Emergency Operating Center) was constructed. We tried to analyze realistically and precisely the situation by changing from the existing field-centered management to sensor-centered management that measures coordinates and provides in real-time data of measuring/monitoring sensors installed at a field site and developing related viewer programs. In addition, the 3D based monitoring management system, which has alarm functions in case of emergency and provides information about the evacuation place, was constructed on the base that is able to expand to nationwide fields by using Vworld 3D map. Ten steep slope monitoring sites were registered on Web-EOC slope monitoring management system constructed in the research and then application instances were suggested.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.9
• /
• pp.2133-2138
• /
• 2013

In this paper, the variation of a steep subthreshold slope at elevated temperature in nanowire n-channel junctionless and inversion mode MuGFETs has been compared. It has been observed that the subthreshold slopes are increased with the increase of the operation temperature in junctionless and inversio-mode transistors. The variation of a subthreshold slope with operation temperature is more significant in junctionless transistor than inversion-mode transistor. The temperature dependence on the variation of a subthreshold slope for different fin widths shows a similar behavior regardless of fin width. From the temperature dependence on the variation of a subthreshold slope for different substrate biases, it has been observed that the variation of a subthreshold slope is less significant when the substrate bias was applied. It is worth noting that one can achieve a subthreshold slope of below 41mV/dec at elevated temperature of 400K using the junctionless MuGFETs with a positive substrate bias.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.16 no.2
• /
• pp.113-120
• /
• 2002

This paper describes characteristics of transient voltage waveforms caused by human electrostatic discharges(ESDs). For purpose of achieving the statistics on the meaningful amplitude and initial slope for transient ESD voltage waveforms, transient voltages due to human ESDs in various conditions were observed. A voltage measuring system with a wide bandwidth from DC to 400[MHz] was employed. ESD voltage waveforms are approximately the same as ESD current waveforms. Also the simulated results, which are calculated by the reposed equivalent circuit, are closely similar to the measured voltage waveforms. ESD voltage waveforms are strongly dependent on the approach speed and material of intruder, a fast approach causes ESD voltage waveform with a steep rise time than for a slow approach. The voltage waveforms from dialect finger ESDs have a relatively long rise time of 10∼30[ns], but their peaks are low. On the other side ESD voltage waveforms causer by screwdriver with insulating handle have a steep slope with a very short, less than 1[ns] rise time, but their initial spikes are extremely high The obtained results in this work would be applied to solve ESD problems for low voltage and small current electronic devices.

• Journal of Environmental Impact Assessment
• /
• v.15 no.6
• /
• pp.357-372
• /
• 2006

The excessive land activities in farming can cause soil erosion, inundation by a flood, and fallow. So far land evaluation has been analyzed using the land use limitation derived from the excessive land activities. This study was done for evaluating the agricultural fields by using 3 land use limitations, inundation potential, soil erodibility potential, and fallow potential. The study area is Ibang-myeon, Changnyeong-gun, Gyeongnam-province, Korea. A logistic regression model was applied to recognize the inundation potential by a flood in the Nakdong river basin. And potential soil erodibility index (PSEI) was derived from USLE model to analyze the soil erodibility potential. And a probability model from a logistic regression model was applied to detect the fallow potential. Therefore, we found 220.7ha for the 4th grade and 86.1ha for the 5th grade was analyzed as water damage potential. Large area near Nakdong river have problem to grow the rice due to the damage by water inundation. And 213.6ha for the 3rd grade and 103.3ha for 4th grade was detected as a result of the analysis of soil erosion potential. The soil erosion potential was high when within-field integrity of soil was not stable, or the kinetic energy was high or the slope length was long due to a steep slope of a specific land. And 869.1ha for 3rd grade, 174.9ha for 4th grade, and 110.6ha for 5th grade was detected to be distributed having the fallow potential. Especially, a village, having a steep mountain, had 249.5ha for the 3rd grade, which was 28.7% of total area showing the 3rd grade. Finally, Three villages, including An-ri, Geonam-ri, Songgok-ri, showed they had largest area of the suitable land in the study area. These villages had similar topographic condition where they were far from Nakdong river, and they had relatively higher elevation and flat lands.

• Microbiology and Biotechnology Letters
• /
• v.34 no.1
• /
• pp.52-57
• /
• 2006

For the purpose of production of a novel antihyperlipemial HMG-CoA reductase inhibitor from bacteria, a bacterium which showed the highest HMG-CoA reductase inhibitory activity was isolated from traditional Doenjang. This strain was identified as Bacillus cereus (D-3) based on its microbiological characteristics and 165 rRNA sequence analysis. The maximal HMG-CoA reductase inhibitor production from Bacillus cereus D-3 was obtained by cultivation in a Glucose-CSL broth containing 2% glucose, 0.6% corn steep liquor, $0.04%\;K_{2}HPO_4$ and $0.05%\;KH_{2}PO_4$ at $30^{\circ}C$ for 36 h. The final HMG-CoA reductase inhibitory activity under the above conditions was 39.4%.

• Microbiology and Biotechnology Letters
• /
• v.17 no.2
• /
• pp.148-153
• /
• 1989

A strain of alkalophilic Bacillus sp. YC-335 has been isolated from soil. The strain was capable of producing large amount of cyclodextrin glycosyl transferase (CGTase) in the culture broth. The preferable medium composition has been determined to be as follows : 1.5% soluble starch, 5% corn steep liquor, 0.1% $K_2$HPO$_4$, 0.02%mgSO$_4$.7$H_2O$, 1% CaCO$_3$and 1% Na$_2$CO$_3$(pH 10.3). The highest enzyme production was observed after 48 hours of cultivation at 31$^{\circ}C$. The optimum pH and temperature for the activity of crude enzyme were 6.0 and 5$0^{\circ}C$, respectively. The enzyme was stable between pH 5 and 9, and upto 5$0^{\circ}C$. The enzyme converted starch into $\alpha$-, $\beta$- and ${\gamma}$-CD in the relative amounts of 1:10:1.5, respectively.

• Journal of Korea Water Resources Association
• /
• v.31 no.2
• /
• pp.167-176
• /
• 1998

On steep hillslopes, saturation zone formations and subsurface flows were monitored through the observation systems of observation wells, tensiometers and trenches. By the 103 mm rain which had fallen on the hillslope with dry soil moisture, the saturation zone began to be formed at the top of hillslope during the rain and developed to be formed within a few hours after the end of rain on all hillslope. Subsurface water outflowed mainly from the soil profile of 0-40 cm depth, but did not outflow from the one of 40-80 cm depth. This saturation zone seemed to be formed by partially saturation of soil. This resulted for two reasons. Firstly, the saturation zone was formed by a smaller amount of rain than that required. Secondly the soil at a certain depth below the water table was unsaturated. Saturation zones formed by pre-rains responded rapidly to rains and subsurface water outflowed mainly from the soil profile of 40-80 cm depth simultaneously with the rising of the water level. The rates of subsurface discharge from the soil profile of 40-80 cm depth to the precipitation were related to the antecedent precipitation although the maximum water levels of saturation zone formed by four rains were similar.

• Korean Journal of Food Science and Technology
• /
• v.22 no.1
• /
• pp.99-104
• /
• 1990

The effects of concentrations of sulfur dioxide (0.16-0.20%) and steeping times (25-50hr) at $52^{\circ}C$ on the changes in pH of steep water and weight and volume of corn and starch properties were investigated. The pH of steep water increased and remained constant after steeping time of 20 hours. The degree of weight or volume gain decreased as the concentration of sulfur dioxide increased. The protein content of starch increased as the concentration of sulfur dioxide increased. Water·binding capacity of starch showed the highest value at the steeping time of 35 hours. Swell ins power and solubility decreased as cocentration of sulfur dioxide and steeping time increased. The initial pasting temperature and peak viscosity were increased and decreased, respectively, as the concentration of sulfur dioxide increased. At the same concentration of sulfur dioxide, the peak viscosity was increased and then decreased. Viscosity of starch in sodium hydroxide solution tended to decrease as the concentration of sulfur dioxide and sleeping time increased. The gel volume of starch in 3M KSCN solution was not affected by concentration of sulfur dioxide and steeping time.

• Journal of Wetlands Research
• /
• v.21 no.1
• /
• pp.9-15
• /
• 2019

The Daegi-cheon watershed is located in the upper part of the Han River, which has the representative highland vegetable growing complexes. This watershed has a large impact on the water quality and aquatic ecosystem in the upstream of the Han River by discharging a large amount of turbid water during rainfall season. For proposing an efficient turbid water management and policy, the analysis of the characteristics of flow rate and SS and its causes needs to be carried out preferentially. In this study, the relationship between flow rate and SS concentration was analyzed in the Daegi-cheon watershed, and in turn the turbidity characteristics were analyzed. As a result of the study, in the normal flood flow condition, it was shown that SS concentration changed arbitrarily due to various environmental factors. On the other hand, the SS concentration was considerably high in the very high flow condition. Based on the field survey, this could be the reason why the effects of the steep valley and slope collapse according to the very high flow rate as well as the source in the agricultural fields were greatly contributed. Therefore, it is necessary to develop a structural best management practice that can stabilize the steep slope and reduce river bed loss along with the typical source managements plans.

• Journal of Korea Water Resources Association
• /
• v.34 no.5
• /
• pp.561-566
• /
• 2001

This study is the analysis of hydraulic characteristic for stream diversion reach by numerical model test. Through it we can provide the basis data in flood, and in grasping stream flow characteristics. Analysis of hydraulic characteristics in Seoknam stream were implemented by using computer model HEC-RAS(one-dimensional model) and RMA2(two-dimensional finite element model). As a result we became to known that RMA2 to simulate left, main channel, right in stream is more effective method in analysing flow in channel bends, steep slope, complex bed form effect stream flow characteristics, than HEC-RAS.