• Journal of the Korean Society of Groundwater Environment
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• v.3 no.2
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• pp.101-109
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• 1996

DRASTIC system was used in this study that was developed by U.S. EPA and is widely used for evaluating relative groundwater pollution potential by using hydrogeological factors. The DRASTIC system can be used for selection of well sites, selection of waste disposal sites and basic data of landuse for groundwater protection, and monitoring purpose and efficient allocation of resource for remediation. This study analyzed regional groundwater pollution potential around Chungju Lake using the DRASTIC system. Hydrogeological factors used in this study are depth to water, net recharge, aquifer media, soil media, slope and hydraulic conductivity. For accurate analysis, lineament density that is extracted from image processing of satellite image is overlaid to the DRASTIC system. Results of this study are mapped so groundwater pollution potential and risk degrees can be understood easily and quickly. A graphic user interface is developed to process the data conveniently.

• The Journal of the Korea Contents Association
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• v.18 no.9
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• pp.606-613
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• 2018

The purpose of this study is to investigate on Humint, one of the intelligence activity conducted by police officer to prevent the possibility of crime in advance and to handle crime in short time. Also, this study aims to identify how interpersonal relationship of police influences Humint acquisition in order to find out the influence of Humint on actual policy activity. For completion, this study conducted survey on current police officer and developed the study based on these data. Humint refers to information acquired by contact between people and to information acquired by intangible contact. Humint, the intangible information, is delivered fast and identifies the other's hidden intention. Humint also approaches inaccessible information and has strength of acquiring information based on five senses instead of using machine. Humint plays vital role in human relations. The investigation on the influence of level, trust, and range of human relations on Humint application demonstrated that people with wide human relations applied Humint effectively on identifying trend. Also, people with wide range of human relations used Humint effectively when utilizing information to handle the crime.

• Korean Journal of Cognitive Science
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• v.14 no.4
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• pp.9-19
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• 2003

Bonneh, Cooperman and Sagi (2001) reported that when a global moving pattern was superimposed on high-contrast stationary stimuli, the latter disappeared and reappeared alternatively for periods of several seconds. They named this as motion-induced-blindness. In present research a rotating transparent cylinder composed of white dots was superimposed on a stationary green dots. When observers watched these stimuli wearing a red filter on his/her right eye, the stationary green dots disappeared or reappeared as did in Bonneh et al. The new MIB was observed only when the cylinder rotated and observers weared a red filter. As the luminance contrast of the green dots and that of white dots against the background reduced, and as the number of green dots and white dots decreased, the duration of MIB reduced. Also, the relative depth of the rotating cylinder and the stationary green dots affected the duration of MIB. These results imply that the new MIB is different from the MIB which was observed by Bonneh et al and that the new MIB cannot be explained by binocular rivalry. Further more, the results imply that the later stage of visual information processing is involved in the new MIB.

• Journal of Korean Society of Steel Construction
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• v.12 no.6
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• pp.701-713
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• 2000

In this study, the 4-point bending test been performed in order to estimate effect of grinding on fatigue characteristics quantitatively for as-welded specimen, grinding specimen & TIG-dressing specimen for non load-carrying fillet welded joints subjected to pure bending. As a result of fatigue tests, fatigue strength at $2{\times}106$cycles of grinding specimen and TIG-dressing specimen has been increased compared with as-welded specimen and satisfied the grade of fatigue strength prescribed in specifications of domestics and AASHTO & JSSC. As a result of beachmark test, fatigue cracks on all specimens have occurred at several points where stress

• Geotechnical Engineering
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• v.3 no.1
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• pp.39-52
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• 1987

Model pile tests are performed, first, to estimate donwndrag exerted on pile surfaces due to the settlement of surrounding soils, and, second, to evaluate the efficiency of the downdrag reduction methods such as the bitumen coating method and the method of the attachment of an enlarged base. Test results show that the downdrag forces may be expressed as 0.25(;effective overburden). Bitumen coating reduces the downdrag by more than 50 percent, and the enlarged base attachment method is also effective, whose effectiveness increases as the sixte of the base increases as expected. When the bitumen coating and enlarged base are both applied, the downdrag force is reduced as much as 90 percent. Finally, it is found that the quantity of the relative displacement between the pile and the surrounding soil downdrag is extremely small.

• 전자공학회논문지 IE
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• v.46 no.1
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• pp.23-30
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• 2009

In this paper, the intelligent vision system for an effective and intelligent path-planning of an industrial AGV system based on stereo camera system is proposed. The depth information and disparity map are detected in the inputting images of a parallel stereo camera. The distance between the industrial AGV system and the obstacle detected and the 2D Path coordinates obtained from the location coordinates, and then the relative distance between the obstacle and the other objects obtained from them. The industrial AGV system move automatically by effective and intelligent path-planning using the obtained 2D path coordinates. From some experiments on AGV system driving with the stereo images, it is analyzed that error ratio between the calculated and measured values of the distance between the objects is found to be very low value of 2.5% on average, respectably.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.11
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• pp.101-106
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• 2005

A ground penetrating image radar (GPR) using an ultra wideband (UWB)impulse waveform is developed for non destructive detection of metallic pipelines buried under the ground. Dielectric constant of test field is measured and then a GPR system is designed for better detection up to 1 meter deep. By considering total path loss, volume of complete system, and resolution, upper and lower frequencies are chosen. First, a UWB impulse for the frequency bandwidth of the impulse is chosen with rising time less than 1 ns, and then compact planar UWB dipole antenna suitable for frequency bandwidth of a UWB impulse is designed. Also, to receive reflected signals, a digital storage oscilloscope is used. For measurement, a monostatic technique and a migration technique are used. For visualizing underground targets, simple image processing techniques of A-scan removal and B-scan average removal are applied. The prototype of the system is tested on a test field in wet clay soil and it is shown that the developed system has a good ability in detecting underground metal objects, even small targets of several centimeters.

• Korean Journal of Environment and Ecology
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• v.5 no.1
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• pp.68-78
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• 1991

To investigate edge vegetation structure and species in the Chrisan National Park, filed survey was excuted from August to October, 1991 and the results were as follows. Importance values of species in lower layer were changed according to the distance from edge to forest interior at the northeastern slope of a highland. Change of vegetation structure was observed from edge up to 30m of forest interior and edge depth was estimated as 15~20m. The dominance and frequency of edge species seemed to be affected by the factors of altitude, aspect and topographic location. Especially, edge vegetation showed severe difference according to topographic location between a ridge and a foot of a mountain, and according to aspect between southern and northern slope above midslope region of a mountain. Comparing vegetation structure of lower layer for southern and northern slope, more no. of individuals and crown coverage were observed at northern slope, while more no. of species, species diversity and coverage of Sasa purpurascen at southern slope.

• Journal of Korean Tunnelling and Underground Space Association
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• v.9 no.1
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• pp.49-62
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• 2007

A new earth pressure equation acting on the vertical shafts in cohesionless soils has been proposed by modifying the equations proposed by others. In order to verify the modified equation, model tests which can control uniform wall displacement with depth to radial direction were conducted. Model tests were performed with three different wall friction angles and two different relative densities. The measured values were larger than estimated values when assuming $\lambda=1$ ; smaller than those when assuming $\lambda=1-sin\phi$. The parameter, $\lambda$ is the ratio of tangential stress to vertical stress and is the most critical value in proposed equation. A method which can estimate the earth pressure on vertical shafts in layered soils is also proposed by reasonably assuming the failure surface of layered soils and using the modified equation. In order to verify the proposed method, in-situ measurement data have been collected from the three in-situ vertical shafts installed in layered soils. Most of earth pressures converted from measured data match reasonably well with estimated values using proposed method.

• Journal of Internet Computing and Services
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• v.7 no.1
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• pp.65-74
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• 2006

Human tracking is a requirement for the advanced human-computer interface (HCI), This paper proposes a method which uses a component-based human model, detects body parts, estimates human postures, and animates an avatar, Each body part consists of color, connection, and location information and it matches to a corresponding component of the human model. For human tracking, the 2D information of human posture is used for body tracking by computing similarities between frames, The depth information is decided by a relative location between components and is transferred to a moving direction to build a 2-1/2D human model. While each body part is modelled by posture and directions, the corresponding component of a 3D avatar is rotated in 3D using the information transferred from the human model. We achieved 90% tracking rate of a test video containing a variety of postures and the rate increased as the proposed system processed more frames.