• Journal of Korea Water Resources Association
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• v.40 no.12
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• pp.1007-1014
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• 2007

Recently, existing river improvement methods for flood control purpose have changed into nature friendly river improvement methods and the efforts to improve the river environment including river restoration have been made, and close-to-nature river improvement and nature friendly river restoration are actively conducted all over the country. In the present situation where various revetment methods are used after the introduction of the concept of close-to-nature river improvement, the environmental characteristics of rivers need to be considered to apply more suitable revetment methods. Therefore, as a precedent study for the development of revetment evaluation techniques and methods for close-to-nature river improvement, the present study suggested evaluation techniques using detailed survey items through field survey. Evaluation items of hydraulic stability consist of mode of streamline, stream bed gradient, flow velocity and tractive force ratio and those of environmental efficiency consist of revetment of vegetation, state of river water, land use of the terrace land on the river, vegetation and materials of the terrace land on the river. Each item was graded with the point 1 through 5. Hydraulic stability and environmental efficiency was evaluated by the points which were averaged in each items. As the result of the application of the proposed evaluation technique, it was found that a number of existing revetments excessively focus on hydraulic stability with little consideration about environmental term. It is expected that the proposed technique in the present study can be used as a base for providing guidelines to construct the design and construction of revetments in the future.

• Proceedings of the Korean Vacuum Society Conference
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• 1998.02a
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• pp.77-77
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• 1998

Present silicon dioxide (SiOz) 떠m as intennetal dielectridIMD) layers will result in high parasitic c capacitance and crosstalk interference in 비gh density devices. Low dielectric materials such as f f1uorina뼈 silicon oxide(SiOF) and f1uoropolymer IMD layers have been tried to s이ve this problem. I In the SiOF ftlm, as fluorine concentration increases the dielectric constant of t뼈 film decreases but i it becomes unstable and wa않r absorptivity increases. The dielectric constant above 3.0 is obtain어 i in these ftlms. Fluoropolymers such as polyte$\sigma$따luoroethylene(PTFE) are known as low dielectric c constant (>2.0) materials. However, their $\alpha$)Or thermal stability and low adhesive fa$\pi$e have h hindered 야1리ru뚱 as IMD ma따"ials. 1 The concept of a plasma processing a찌Jaratus with 비gh density plasma at low pressure has r received much attention for deposition because films made in these plasma reactors have many a advantages such as go여 film quality and gap filling profile. High ion flux with low ion energy in m the high density plasma make the low contamination and go어 $\sigma$'Oss피lked ftlm. Especially the h helicon plasma reactor have attractive features for ftlm deposition 야~au똥 of i앙 high density plasma p production compared with other conventional type plasma soun:es. I In this pa야Jr, we present the results on the low dielectric constant fluorocarbonated-SiOF film d밑JOsited on p-Si(loo) 5 inch silicon substrates with 00% of 0dFTES gas mixture and 20% of Ar g gas in a helicon plasma reactor. High density 띠asma is generated in the conventional helicon p plasma soun:e with Nagoya type ill antenna, 5-15 MHz and 1 kW RF power, 700 Gauss of m magnetic field, and 1.5 mTorr of pressure. The electron density and temperature of the 0dFTES d discharge are measUI벼 by Langmuir probe. The relative density of radicals are measured by optic허 e emission spe따'Oscopy(OES). Chemical bonding structure 3I피 atomic concentration 따'C characterized u using fourier transform infrared(FTIR) s야3띠"Oscopy and X -ray photonelectron spl:’따'Oscopy (XPS). D Dielectric constant is measured using a metal insulator semiconductor (MIS;AVO.4 $\mu$ m thick f fIlmlp-SD s$\sigma$ucture. A chemical stoichiome$\sigma$y of 야Ie fluorocarbina$textsc{k}$영-SiOF film 따~si야영 at room temperature, which t the flow rate of Oz and FTES gas is Isccm and 6sccm, res야~tvely, is form려 야Ie SiouFo.36Co.14. A d dielec$\sigma$ic constant of this fIlm is 2.8, but the s$\alpha$'!Cimen at annealed 5OOt: is obtain려 3.24, and the s stepcoverage in the 0.4 $\mu$ m and 0.5 $\mu$ m pattern 킹'C above 92% and 91% without void, res야~tively. res야~tively.

• Journal of Korean Society of Rural Planning
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• v.6 no.1 s.11
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• pp.19-28
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• 2000

Now in order to overcome the weakest points of the rural areas of the city of Kimje and, transform them into rural cultural villages which have local governing systems suitable to new localization age and activate this plan, we selected Daesan Village as a model village which had shown a lot of potentials in the basic research and studied it dividing it into the former part and the latter part. We studied Daesan village in the former part focusing on state analysis and basic ideas and in the latter part focusing on master plan and detail planning. We can summarize the conclusion like the followings. 1. Daesan Village located 8 kilometer away from the downtown Kimje and the city of Iksan respectably has comparatively good environment of good sunny place as an open field whose surrounding configuration of the ground consists of farming lands and low hills in front and rear. It has 38 farming households in all. 2. Human environment(인문환경); the village road whose width is about 4 meters is forming a flow system forking off into three. There is a route bus which operates three times a day even into the inside of the village. The main sources of revenue are vegetables in facilities, fruits and floriculture. Their average revenue is about 10.5 million won. 3. Here in DaeSan Village a legend dealing with Teasan literally meaning a big mountain consist of th village's tradition and you can see the tombs of a very faithful son and Anwi an army general in the age of the Japanese Invasion of Korea of 1592 to 1598 inside the village. 4. 85 out of the eitire population 141 whose age are over 20 showed very positive attitudes in a questionnaire about, making the village a cultural one and its development. 5. The basic of planned ideas is to increase the revenue of the farming household by making the village a professional farming one which has a state-of the-art production facility and agricultural technique. It is to make the village the one where people can enjoy the sense of the rural life and the farmer can enjoy their lives through consumptive and consistant leisure and resting activities. 6. We are planning to make entrance space, life space, rest and sport space, and cultural space considering the characteristics of the village and the demand of the resident. We are also planning to make tile entire city of Kimje an information transmitting base in short and long term perspectives. 7. DaeSan Village was planned as a place where tradition and the future exist together. On the basis of this concept we planned future programs for Daesan Village and in the latter part of the study master plans and detail plans will be continued.the regional agricultural condition. The development permissions were only during the period of restricted to use ($1979.12{\sim}1993.11$). We propose that the authority of development permission should be given to the local autonomy government, because the local government has the knowledge of its individual agricultural conditions.

• Economic and Environmental Geology
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• v.43 no.4
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• pp.371-379
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• 2010

Fresh water injection test in a fractured bedrock aquifer was applied as an efficient approach to lower saline concentrations in the saltwater-freshwater transition zone formed by seawater intrusion in a coastal area. The methodology and effectiveness of fresh water injection for hydraulically controlling seawater intrusion is overwhelmingly site dependent, and there is an urgent need to characterize the permeable fractures or unconsolidated porous formations which can allow for seawater flow and transport. Considering aquifer characteristics, injection and monitoring boreholes were optimally designed and completed to inject fresh water through sand layer and fractured bedrock, respectively. We devised and used the injection system using double packer for easy field operation and maintenance. Overall fracture distribution was systematically identified from borehole image logs, and the section of fresh water injection was decided from injection test and monitoring. With fresh water injection, the fluid electrical conductivity of the monitoring well started to be lowered by the inflow of fresh water at the specific depth. And this inflow leaded to the replacement of the fluid in the upper parts of the borehole with fresh water. Furthermore, the injection effect lasted more than several months, which means that fresh water injection may contribute to the mitigation of seawater intrusion in a coastal area.

• Sleep Medicine and Psychophysiology
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• v.5 no.2
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• pp.119-133
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• 1998

Attentional processes facilitate cognitive and behavioral performance in several ways. Attention serves to reduce the amount of information to receive. Attention enables humans to direct themselves to appropriate aspects of external environmental events and internal operations. Attention facilitates the selection of salient information and the allocation of cognitive processing appropriate to that information. Attention is not a unitary process that can be localized to a single neuroanatomical region. Before the cortical registration of sensory information, activation of important subcortical structures occurs, which is called as an orienting response. Once sensory information reaches the sensory cortex, a large number of perceptual processes occur, which provide various levels of perceptual resolution of the critical features of the stimuli. After this preattentional processing, information is integrated within higher cortical(heteromodal) systems in inferior parietal and temporal lobes. At this stage, the processing characteristics can be modified, and the biases of the system have a direct impact on attentional selection. Information flow has been traced through sensory analysis to a processing stage that enables the new information to be focused and modified in relation to preexisting biases. The limbic and paralimbic system play significant roles in modulating attentional response. It is labeled with affective salience and is integrated according to ongoing pressures from the motivational drive system of the hypothalamus. The salience of information greatly influences the allocation of attention. The frontal lobe operate response selection system with a reciprocal interaction with both the attention system of the parietal lobe and the limbic system. In this attentional process, the search with the spatial field is organized and a sequence of attentional responses is generated. Affective, motivational and appectitive impulses from limbic system and hypothalamus trigger response intention, preparation, planning, initiation and control of frontal lobe on this process. The reticular system, which produces ascending activation, catalyzes the overall system and increases attentional capacity. Also additional energetic pressures are created by the hypothalamus. As psychophysiological measurement, skin conductance, pupil diameter, muscle tension, heart rate, alpha wave of EEG can be used. Event related potentials also provide physiological evidence of attention during information process. NI component appears to be an electrophysiological index of selective attention. P3 response is developed during the attention related to stimulus discrimination, evaluation and response.

• Journal of Korean Society for Geospatial Information Science
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• v.3 no.2 s.6
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• pp.101-113
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• 1995

In pipeline planning, the systematic and reasonal management of topographical and spatial data are needed in order to omprove the availibilities for data analysis and the effective combinations of spatial informations. According to that fact, DBMS (Database Management System) and DSS(Decision making Support System) have to be developed for the planning of water supply system Also, the economic selection for harmonious delivery of water to target area, since the alternatives of pre-designed pipeline are influenced by hydraulic stability and geographic characteristics. In this study, GIS technique for water supply planning and management which stores graphic features and attributes as digital data sets is considered and engineering application programs are integrated for effective planning of water supply system. Decision making support system based on analyzing technical, Social and economical aspects is developed for the extension of water supply facilities and pipeline configurations. Especially, Hydraulic, land-use and economic influences are considered as important factors for the purpose of developing the system. Hydraulic analysis program(SAPID) for pipeline flow which is already developed in Water Resources Research Institute and economic analysis program(ECOVEL) are integrated with GIS for resonable decision making. Every possible aspects in pipeline planning for water supply is reviewed and the applicabilities of developed system into the field are evaluated.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.2
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• pp.92-108
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• 2017

Present work shows a numerical method to analysis of interaction analysis between solitary wave and onshore bridge. Numerical simulation is carried out by TWOPM-3D (three-dimensional one-field model for immiscible two-phase flows), which is based on Navier-Stokes solver. To do this, the solitary wave is generated numerically in numerical wave channel, and numerical results and experimental results were compared and analyzed in order to verify the applicability of force acting on an onshore bridge. From this, we discussed precisely the characteristics of horizontal and vertical forces (uplift and downward forces) changes including water level and velocity changes due to the variation of solitary wave height, water depth, onshore bridge's location and type, and number of girder. Furthermore, It is revealed that the maximum horizontal and vertical forces acting on the girder bridge show different varying properties according to the number of girder, although each maximum force acting on the girder bridge is proportional to the increasement of incident solitary wave height, and the entrained air in the fluid flow affects the vertical force highly.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.1
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• pp.39-47
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• 2020

In order to investigate current characteristics at the Gungpyung beach, which is a macrotidal flat, field measurements were carried out in the summer and winter at the intertidal and the subtidal zones. The distribution of residual current at intertidal flat was dominant in the northward direction in the summer and dominant in the northward and southwestern directions in the winter. The direction and speed of the residual current in the winter are highly correlated with the significant wave height, and the turbidity is also highly correlated with the significant wave height. Therefore, in the winter, high sediment rates are suspended by high waves, and sediments are transporting due to the residual current in the southwest direction. On the other hand, it is expected that the northward residual current is predominant due to the small wave in the summer, and sediment transport does not occur largely due to less suspended sediments. In addition, sediment transport in the southern direction is blocked by the dock, which is the artificial structure, and the erosion occurs in the south side of the dock. The erosion pattern in the macrotidal zone of Yellow sea is dominated by seasonal waves, and blocking of sediments by artificial structure is very important.

• Journal of Korean Society of Transportation
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• v.35 no.3
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• pp.220-233
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• 2017

Traffic volumes are fundamental data widely used in various traffic analysis, such as origin-and-destination establishment, total traveled kilometer distance calculation, congestion evaluation, and so on. The low number of links collecting the traffic-volume data in a large urban highway network has weakened the quality of the analyses in practice. This study proposes a method to estimate the traffic volume data on a highway link where no collection device is available by introducing a spatial statistic technique with (1) the traffic-volume data from TOPIS, and National Transport Information Center in the Ministry of Land, Infrastructure, and (2) the navigation data from private navigation. Two different component models were prepared for the interrupted and the uninterrupted flows respectively, due to their different traffic-flow characteristics: the piecewise constant function and the regression kriging. The comparison of the traffic volumes estimated by the proposed method against the ones counted in the field showed that the level of error includes 6.26% in MAPE and 5,410 in RMSE, and thus the prediction error is 20.3% in MAPE.

• Journal of Korea Water Resources Association
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• v.38 no.8 s.157
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• pp.645-653
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• 2005

Water cycle analysis in the Cheonggyecheon watershed(river length: 13.75 km, area: $50.96\;km^2$) was performed using WEP model, a physically based distributed rainfall-runoff model. As the application results of the model, the hydrological characteristics of the Cheonggyecheon watershed are significantly consistent with those of a typical urbanized watershed. The direct runoff from the watershed was larger and the evapotranspiration. was lower, and the response of runoff to rainfall was occurred very fast, as compared to forest watersheds. The river channel routing simulation results are similar to the change pattern and scale of the field data. The possible supply period of instream flow from Cheonggyecheoon watershed itself was estimated using WEP. According to the WEP simulation results for the annual water balance of the Cheonggyecheon watershed in 2002, the amount of direct runoff, infiltration and evapotranspiration were 830 mm, 388 mm and 397 mm respectively for an annual precipitation of 1,388 mm. The runoff to rivers was 1,288 mm. And the proportion of direct runoff, intermediate runoff and groundwater runoff were $67.6\%,\;12.7\%$ and $19.7\%$ respectively.