• Resources Recycling
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• v.22 no.2
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• pp.62-70
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• 2013

Electric arc furnace slag is made in ironworks during steel refining, it is been increasing chemical and physical resistibility using ageing method of unstable state of melting steel slag for using concrete's fine aggregates. Which is been changing stable molecular structure of aggregates, it restrains moving of ion and molecule. In Korea, KS F 4571 has been prepared for using the electric arc furnace slag to concrete aggregates. In this study, Electric arc furnace slag is used in the PMC(Polymer Modified Concrete) which is applied a bridge pavement of rehabilitation, largely. In that case, this study evaluates the structural safety about increasing the specific weight. The 4-type bridges(RC slab bridge, RC rigid-frame bridge, PSC Beam bridge, Steel box girder bridge) pavement's increasing the total dead load is in 1 ~ 2%. Design moments in a load combination are increased less then 2%. safety factor is decreased less than 3%. Therefore, the structural safety has no problem for applying the electric arc furnace slag within PMC in bridge.

• International Journal of Highway Engineering
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• v.17 no.2
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• pp.55-62
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• 2015

Cracking is an inevitable fact of asphalt concrete pavements and plays a major role in pavement deterioration. Pavement cracking is one of the main factors determining the frequency and method of repair. Cracks can be treated with a number of preventative maintenance actions, including overlay surface treatments such as slurry sealing, crack sealing, or crack filling. Pavement cracks can show up as one or all of the following types: transverse, longitudinal, fatigue, block, reflective, edge, and slippage. Crack sealing is a frequently used pavement maintenance treatment because it significantly extends the pavement service life. However, crack sealant often fails prematurely due to a loss of adhesion. Because current test methods are mostly empirical and only provide a qualitative measure of the bond strength, they cannot accurately predict the adhesive failure of the sealant. This study introduces a laboratory test aimed at assessing the bonding of hot-poured crack sealant to the walls of pavement cracks. A pneumatic adhesion tensile testing instrument (PATTI) was adopted to measure the bonding strength of the hot-poured crack sealant as a function of the curing time and temperature. Based on a limited number of test results, the hot-poured crack sealants have very different bonding performances. Therefore, this test method can be proposed as part of a newly developed performance-based standard specification for hot-poured crack sealants for use in the future. PURPOSES : The purpose of this study was to evaluate both the adhesion and failure performance of a crack sealant as a function of its curing time and curing temperature. METHODS: A pneumatic adhesion tensile testing instrument (PATTI) was adopted to measure the adhesion performance of a crack sealant as a function of the curing time and curing temperature. RESULTS: With changes in the curing time, curing temperature, and sealant type, the bond strengths were found to be significantly different. Also, higher bond strengths were measured at lower temperatures. Different sealant types produced completely different bond strengths and failure behaviors. CONCLUSIONS: The bonding strength of an evaluated crack sealant was shown to differ depending on various factors. Two sealant types, which were composed of different raw materials, were shown to perform differently. The newly proposed test offers the possibility of evaluating and differentiating between different crack sealants. Based on alimited number of test results, this test method can be proposed as part of a newly developed performance-based standard specification for crack sealants or as part of a guideline for the selection of hot-poured crack sealant in the future.

• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.1
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• pp.169-182
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• 2007

The purpose of this study is to assess the urban amenity on physical environmental factors, and to verify the effectiveness of the amenity map using correlation analysis of the environmental quality. The physical environmental factors were set to 4 items of green space, landscape, water environment and land use, and the items were composed of 11 detail factors. Based on the factors, GIS maps were constructed and the amenity map was produced using overlay analysis. The results of this study are as follow; the proportion of 1~2 ranks was 40.8% of total area around Dalseong-gun, Dong-gu, Suseong-gu. The lower 6~7 ranks in the amenity assessment was 5.7% of total area around Jung-gu, Seo-gu, Dalseo-gu. According to the results of correlation analysis between the amenity and environmental observed data, $SO_2$ among the air pollution material had a negative correlation with amenity(r=-0.649, p<0.05). In case of water pollution, TN and TP had the negative correlations with amenity (r=-0.643, P<0.01; r=0.642, p<0.01).

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.3
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• pp.1-12
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• 2011

Large-sized multi-touch screen is usually made using infrared rays. That is because it has technical constraints or cost problems to make the screen with the other ways using such as existing resistive overlays, capacitive overlay, or acoustic wave. Using infrared rays to make multi-touch screen is easy, but is likely to have technical limits to be implemented. To make up for these technical problems, two other methods were suggested through Surface project, which is a next generation user-interface concept of Microsoft. One is Frustrated Total Internal Reflection (FTIR) which uses infrared cameras, the other is Diffuse Illumination (DI). FTIR and DI are easy to be implemented in large screens and are not influenced by the number of touch points. Although FTIR method has an advantage in detecting touch-points, it also has lots of disadvantages such as screen size limit, quality of the materials, the module for infrared LED arrays, and high consuming power. On the other hand, DI method has difficulty in detecting touch-points because of it's structural problems but makes it possible to solve the problem of FTIR. In this thesis, we study the algorithms for effectively correcting the distort phenomenon of optical lens, and image processing algorithms in order to solve the touch detecting problem of the original DI method. Moreover, we suggest calibration algorithms for improving the accuracy of multi-touch, and a new tracking technique for accurate movement and gesture of the touch device. To verify our approaches, we implemented a table-based multi touch screen.

• Journal of the Korean Geographical Society
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• v.48 no.1
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• pp.1-18
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• 2013

The mountain region in Korea has been known as 70% of total area and most Korean people have recognized Korea as the mountainous country. Those concepts are thought to be mislead by the definition of the Korea Forest Service for the mountain region. According to KFS's definition based on the land-use, the forest and farmland at the low altitude are also included in the mountain region. In this study, firstly, the geomorphological mountain region is extracted according to the definition of Kapos et al. (2000). The rates of mountain region in S. Korea, N. Korea, Korea Peninsular are 31%, 51%, 42% respectively. And the rates between mountain area and non-mountain area in the 300-1000m and 1000-2500m intervals are considerably different due to the existence of plateaus such as high-level plain surfaces. Secondly, using the overlay analysis in GIS, the distribution of mountain areas are compared with that of order-mountains' areas defined by Qui and SON (2010). Even in case of the 5th order, the highest order mountains, the hill & plain and non-mountain areas are included in that mountain area. It is possible to suggest that the definition of the KFS is completely different from the academic, realistic and epistemic definition for mountain area, and the geomorphological definition of mountain area is useful to classify the mountain area according to the its physical properties. Therefore, it would be expected that the definition contributes the development of methodologies on the scientific management of mountain area in future.

• Journal of the Korea Concrete Institute
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• v.17 no.3 s.87
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• pp.329-334
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• 2005

The use of Polymer Concrete (PC) is growing very rapidly in many structural and construction applications such as box culverts, hazardous waste containers, trench lines, floor drains and the repair and overlay of damaged cement concrete surfaces in pavements, bridges, etc. However, PC has a defect economically because resin which be used for binder is expensive. Therefore the latest research is being progressed to replace existing resin with new resin which can reduce the high cost. Here, Polymer concrete using the recycled PET(polyethylene terephthalate) has some merits such as decrease of environmental destruction, decrease of environmental pollution and development of new construction materials. The variables of this study are amount of resin, curing condition and maximum size of coarse aggregate to find out mechanic properties of this. Stress-strain curve was obtained using MTS equipment by strain control. The results indicated that modulus of elasticity was increased gradually in an ascending branch of curve, as an increase of resin content. Compressive strength was the highest for resin content of $13\%$. And Compressive strength was increased as maximum size of coarse aggregate increases. The strain at maximum stress increases with an increase of resin content and size of coarse aggregate. For the descending branch of stress-strain curve the brittle fracture was decreased when it was cured at the room temperature compared to high temperature.

• Spatial Information Research
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• v.20 no.1
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• pp.47-57
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• 2012

An Administrative Boundary is the basic of spatial information to cover geographical and regional area. Its importance has arisen in our society at the Smart world era. However, it is difficult to serve exact boundary's lines as administrative boundaries are based on the cadastre lines of land register ; these partly are overlay each other or has gaps. So, it Should be adjusted. But, the maintenance work of administration boundaries causes a conflict or confusion unless we offer concrete procedures and detailed plans previously. Therefore, a rational method is required to prevent side-effects such as confusion, disagreem ent and a conflict etc. In this Study, we present a method and 5 step procedures to make better use in a practical maintenance work. we researched on basic studies of Administrative boundary's concept, history. And we performed a field survey as well as analysis of current problems. considering these results, we suggest usage of various spatial data sources, stake-holders' participation, a method of Nearest district's boundaries to maintain administrative boundaries. Throughout the method, we expect it to serve correct boundary-data to various fields without a big confusion. it is also useful to apply its results not only for re-surveying our land but for recording appropriate boundary-data as rational lines.

• Spatial Information Research
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• v.17 no.2
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• pp.201-212
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• 2009

As GIS analysis method began to be introduced in late 1980's, studies of land development applying the GIS also started to be proceeded in various fields. Since 2003, Land Suitability Assesment has been adopted in order to prevent national land from development thoughtless for the environment and to plan appropriate national land management in terms of green development. Land Suitability Assessment System II based on diverse GIS analysis method such as Contour Analysis, Overlay Analysis, Network Analysis was particularly adopted to draft plans of specifying and altering of exclusionary zoning as well as installing and maintaining of urban planning facilities. But there has been a lot of problem, like an inaccurate basic data and assessment indicators, unmatched threshold, and contradicted evaluation result between each evaluating systems. Even though it is suited to an evaluation criteria, grade distribution is applied to start at 20, and development-centered evaluation result is offered. Now, we observed how suitability values and grading were changed, ordering to change grade distribution system from $20{\sim}100$ to $0{\sim}100$. In result, it showed changes of grades in some parcels. And in case of suitability values, 87% of parcels decreased to minimum 1 point, maximum 70 points. It means that changing grade distribution system of assessment system II doesn't have only influence on suitability values and grading but it is also an empirical analysis because of considering both development and maintenance.

• Korean journal of applied entomology
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• v.32 no.3
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• pp.307-316
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• 1993

The potential of using GIS in analyzing pest surveillance data was explored. The Spatial Analysis System (SPANS) was used to construct a spatial data base to study pest distributions using pest surveillance data collected from 152 stations in South Korea. The annual spatIal distributions of the striped rice borer(SRB), Chdo suppressalis, showed that high densities started to expand in the early 1980s, reaching a peak in 1988. The pattern change appears to be related to cultivation of japonica and indica-japonica hybrid varieties in South Korea. Japo7l!ca varieties have longer duration resulting in the SRB haVlng more time to mature and hibernate in wmter. The locus of SRB spread appears to be located in the mid-west region near lri, Chun~ Buk Province. High brown planthopper (BPH) populations in South Korea are often related to the early immigration and temperature. The simulated distribution of PPH densities in September using these two factors was compared with the actual distribution obtained using 1990 data. The two density maps corresponded closely excepL for differences in the south eastern valley. By overlaying the simulated map layer with the elevation and rice area maps, more specific BPH risk zones could be identified.

• International Journal of Highway Engineering
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• v.3 no.4 s.10
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• pp.117-126
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• 2001

In this research, evaluation of adhesion in tension property of SBR-modified concrete to ordinary portland cement concrete was conducted with uniaxial direct tensile bond test which was proposed by Kuhlmann. A test set-up was fabricated in order to minimize the eccentric force by introducing a joint which might fully rotate. The main experimental variables were cement-latex ratios, surface preparations and moisture levels. The results obtained were as follows: The LMC specimen at 15% latex-cement ratio increased the adhesion in tension by range of 37% compared to that of conventional cement concrete. This might be due to latex film formed between cement paste and aggregate. The effects of surface preparation on bond of latex modified concrete to conventional concrete were significant at the conditions by sand paper and wire brush. A better bond could be achieved by rough surface rather than smooth. The saturated and surface dry (SSD) condition were considered to be the most appropriate moisture level followed by wet, finally by dry. Thus, a proper surface preparation and moisture level are quite necessity in order to obtain better bonding at LMC overlay.