• Journal of the Korean GEO-environmental Society
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• v.14 no.4
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• pp.53-58
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• 2013

The design for horizontal drain layer on soft ground starts from the decision that the material could be used or not, by verifying material condition in permeability of horizontal drain material according to the weight percent of the dry soil retained on #200 sieve. In the next step of the design, we estimate the thickness of horizontal drain layer to confirm trafficability of heavy machinery in construction work. Successively, the long-term functionality for good drainage of horizontal drain layer is checked and if needed, some means are considered. In this study, the system to recycle mixed coal ash in ash pond successfully as a horizontal drain material on soft ground is presented through the process and the result of its practical construction work. Namely, the pact is confirmed that mixed coal ash in ash pond should be sorted out by sieve screen to a certain extent and the remainders of this mixed coal ash on sieve openings be recycled, because the amount of finer particles than $75{\mu}m$ contained in mixed coal ash in ash pond is quite massive and irregular depending on the coal power plant or the location in same ash pond. In order to sort at large scale in situ, the dimension of a sieve squre hole and the sort-out method, etc. should be decided before the sort-out process. And, it is described that we need to manufacture classifier to sort out mixed coal ash in ash pond, too.

• Korean Journal of Construction Engineering and Management
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• v.19 no.5
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• pp.70-80
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• 2018

Recently, the construction industry has lively utilized system forms to improve the work productivity and safety of form work, and the beam table form is one of them. However, the beam table form is used limitedly for the construction of buildings where the same beam size is applied to every floor. To make it possible to apply the beam table form to a building where different beam sizes are designed according to the uses of floors, it was analyzed that among the components of the beam table form, the beam bracket, should be able to flexible adjust the size of the beam form only with simple operation. Therefore, the purpose of this study is to propose the conceptual design of "an adjustable beam bracket for beam table form" that allows the adjustment of beam form size with simple operation and has excellent applicability to construction sites as well. In case this study's conceptual design of adjustable beam bracket for beam table form is fabricated into a real thing, it is expected that the beam table form will be applicable to even buildings where different beam sizes are designed according to the uses of floors, thereby contributing to the improvement in the work productivity and safety of form work.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.4
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• pp.61-70
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• 2008

This paper designed the antenna for collecting and servicing the traffic information that apply to freeway Traffic Management System, as using DSRC (Dedicated Short Range Communication). Active DSRC is the technology that is using 5.8GHz Radio Frequency to a mean Sequency and there are a lot of the case occurring a physical electric wave shadowing because of the traveling straight of a electric wave. In such inferior communication environment, it constructed the stabilized communication link that can do collecting and servicing the correct traffic information and designed the beam pattern considering the establishment position of the antenna that can apply to various road environments and a communication area. By considering the communication link environment, this paper designed and manufacture the mean frequency of 5.8GHz, the input loss of -17dB in 75MHz bandwidth, the Axial ratio of 1.5:1, and $2{\times}4$ array microstrip antenna which beam pattern have the characteristic of $55^{\circ}$ horizontal half power beam width and $26^{\circ}$elevation half power beam width and the minimum establishment height of the antenna was designed as 14m for avoiding electric wave shadowing on a physical condition between vehicles

• Korean Journal of Remote Sensing
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• v.19 no.4
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• pp.307-317
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• 2003

This paper presents an algorithm that automatically extracts buildings among many different features on the earth surface by fusing LIDAR data with panchromatic aerial images. The proposed algorithm consists of three stages such as point level process, polygon level process, parameter space level process. At the first stage, we eliminate gross errors and apply a local maxima filter to detect building candidate points from the raw laser scanning data. After then, a grouping procedure is performed for segmenting raw LIDAR data and the segmented LIDAR data is polygonized by the encasing polygon algorithm developed in the research. At the second stage, we eliminate non-building polygons using several constraints such as area and circularity. At the last stage, all the polygons generated at the second stage are projected onto the aerial stereo images through collinearity condition equations. Finally, we fuse the projected encasing polygons with edges detected by image processing for refining the building segments. The experimental results showed that the RMSEs of building corners in X, Y and Z were 8.1cm, 24.7cm, 35.9cm, respectively.

• Korean Journal of Remote Sensing
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• v.11 no.3
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• pp.33-47
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• 1995

The representation of point-observed environmental variables in Geographic Information Systems(GIS) has often been inadequate to meet the need of regional-scale ecological and environmental applications. To create a map of continuous surface that would represent more reliable spatial variations for these applications, I present three spatial estimation methods. Using a secondary variable of the proximity to coast line together with rainfall acidity data collected at the 63 acid rain monitoring stations in Korea, average rainfall acidity map was cteated using co-kriging. For comparison, two other commonly used interpolation methods (inverse distance weighting and kriging) were also applied to rainfall acidity data without reference to the secondary variable. These estimation methods were evaluated by both visual assessments of the output maps and the quantitative comparison of error measures that were obtained from cross validation. The co-kriging method produced a rainfall acidity map that showed noticeable improvement in repoducing the inherent spatial pattern as well as provided lower statistical error as compared to the methods using only the primary variable.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.140-148
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• 2019

Large cast iron structures are used in casings and pipes in shipsand chemical plants. Broken parts in the casings and pipescan result in failures even when stresses are below the yield strength of the part's materials. Fatigue failure of a large cast iron structure is inevitable due to the design constraints and low reliability of the material strength. A small structure can be repaired by welding, but a large structure cannot because it cannot be preheated slowly and uniformly. This study shows that a large structure can be repaired by a cold joint method using a crack repair screw. Large cast iron structures were manufactured by GC 300, and their design stress is below 3.5 MPa. The tensile strength on notched specimens repaired by crack repair screws was 8.2 MPa. Therefore, the safety factors of structures repaired by crack repair screws have a value above 2.3 and are considered to be high values.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.5
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• pp.333-340
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• 2019

Tests using a middle velocity propulsion impact machine (MVPIM) were performed to verify the impact resistance capability of sandwich concrete panels (SCP) in a modular liquefied natural gas (LNG) outer tank, and numerical models were constructed and analyzed. $2{\times}2m$ specimens with plain sectional characteristics and specimens including a joint section were used. A 51 kg missile was accelerated above 45 m/s and impacted to have the design code kinetic energy. Impact tests were performed twice according to the design code and once for the doubled impact speed. The numerical models for simulating impact behaviors were created by LS-DYNA. The external steel plate and filled concrete of the panel were modeled as solid elements, the studs as beam elements, and the steel plates as elasto-plastic material with fractures; the CSCM material model was used for concrete. The front plate deformations demonstrated good agreement with those of other tests. However the rear plate deformations were less. In the doubled speed test for the plain section specimen, the missile punctured both plates; however, the front plate was only fractured in the numerical analysis. The impact energy of the missile was transferred to the filled concrete in the numerical analysis.

• Journal of Service Research and Studies
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• v.6 no.3
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• pp.29-40
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• 2016

Since the late 20th century, there has been much effort to improve the market value of media contents which are commercialized in a digital format, by fusing digital data of video, audio, numerals, characters with IT technology together. Then by what criteria and methodologies could the market value for the drama "Sons of the Sun" or the animated film 'Frozen', often referred to in the meida, be estimated? In the circumstances there has been little or no research on the valuation framework of media contents and the status of their valuation system development to date, we propose a practical valuation models for various purposes such as contents trading, review of investment adequacy, etc., by formalizing and presenting a contents valuation framework for the four types of media of movies, online games, and broadcasting commercials, and animations. Therefore, we develope computational methods of cash flows which includes production cost by media content types, provide reference databases associated with key variables of valuation (economic life cycle, discount rates, contents contribution and royalty rates), and finally propose the valuation framework of media contents based on both income approach and relief-from-royalty method which has been applied to valuation of intangible assets so far.

• Journal of the Korea Society of Computer and Information
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• v.25 no.6
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• pp.183-191
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• 2020

In this study, in order to obtain basic data on the development of a new hanbok skirt pattern for developing a customizing system, a new hanbok brand skirt pattern was compared and analyzed. After analyzing the patterns of six new hanbok brands, virtual simulation was performed to evaluate the appearance, clothing pressure, and airgap. As a result of analyzing the waist skirt patterns of commercial new hanbok brands A, B, C, D, E, and F, it was found that they were produced in different dimensions despite the free size skirt of the same design. The pattern of new hanbok waist skirt was composed of a flat pattern like the traditional hanbok. As a result of appearance evaluation, it was evaluated that there were significant differences between the patterns of the six brands in all the evaluation items on the front, side, and back. In the appearance evaluation, it was evaluated that the waist skirt of the B brand was excellent. As a result of examining the color distribution and airgap, it was evaluated that the airgap was large in most parts due to the characteristics of the waist skirt worn around the waist, and the garment pressure was low. In this paper, we propose a basic data for standardizing dimensions and patterns according to activation New Hanbok. It is thought that a unified pattern development based on the B brand pattern should be made.

• Journal of the Korea Society for Simulation
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• v.30 no.3
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• pp.1-9
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• 2021

Commander and staffs on the battlefield are aware of the situation and, based on the results, they perform military activities through their military decisions. Recently, with the development of information technology, the demand for artificial intelligence to support military decisions has increased. It is essential to identify, collect, and pre-process the data set for reinforcement learning to utilize artificial intelligence. However, data on enemies lacking in terms of accuracy, timeliness, and abundance is not suitable for use as AI learning data, so a training model is needed to collect AI learning data. In this paper, a methodology for learning artificial intelligence was presented using the constructive wargame model exercise data. First, the role and scope of artificial intelligence to support the commander and staff in the military decision-making process were specified, and to train artificial intelligence according to the role, learning data was identified in the Chang-Jo 21 model exercise data and the learning results were simulated. The simulation data set was created as imaginary sample data, and the doctrine of ROK Army, which is restricted to disclosure, was utilized with US Army's doctrine that can be collected on the Internet.