• Korean Journal of Construction Engineering and Management
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• v.5 no.2 s.18
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• pp.162-171
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• 2004

Crack sealing is a maintenance procedure that is commonly used to reduce pavement degradation. If cracks in pavements are not sealed, surface water penetration can reduce the strength of the sub-base layers, which can result in increased deflections of the pavement. Reduced strength of the sub-base also accelerates the deterioration of the surface, due to development of greater cracking and potholes. Crack sealing is performed to reduce water and debris penetration, thereby helping to maintain pavement structural capacity and limiting future degradation. The process of sealing cracks in pavements is however dangerous, costly, and labor-intensive operation. Labor turnover and training are increasing problems related to crack sealing crews, and as traffic volumes increase. Automating crack sealing can reduce labor and road user costs, improve work quality, and decrease worker exposure to roadway hazards. The main objective of this research is to develop an automated system for sealing cracks in pavement. Extension of the algorithms and tools presented in this research is also recommended for future study.

• Korean Chemical Engineering Research
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• v.45 no.3
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• pp.242-248
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• 2007

For an optimal design of automotive electric system, it is important to have a reliable modeling tool to predict the charge-discharge behaviors of the automotive battery. In this work, a two-dimensional modeling was carried out to predict the charge-discharge behaviors of a 12-V automotive lead-acid battery. The model accounted for electrochemical kinetics and ionic mass transfer in a battery cell. In order to validate the modeling, modeling results were compared with the experimental data of the charge-discharge behaviors of a lead-acid battery. The discharge behaviors were measured with three different discharge rates of C/5, C/10, and C/20 at operating temperature of $25^{\circ}C$. The batteries were charged with constant current of 30A until the charging voltage reached to a predetermined value of 14.24 V and then the charging voltage was kept constant. The discharge and charge curves from the measurements and modeling were in good agreement. Based on the modeling, the distributions of the electrical potentials of the solid and solution phases, the porosity of the electrodes, and the current density within the electrodes as well as the acid concentration can be predicted as a function of charge and discharge time.

• Journal of the Korean GEO-environmental Society
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• v.9 no.2
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• pp.39-46
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• 2008

Due to the growth in industrialization, potential hazards in subsurface environments are becoming increasingly significant. The extraction of the contaminant from the soil and movement of the water are restricted due to the low permeability and adsorption characteristics of the reclaimed soils. There are a number of approaches to in-situ remediation that are used in contaminated sites for removing contaminants. These include soil flushing, dual phase extraction, and soil vapor extraction. Among these techniques, soil flushing was the focus of the investigation in this paper. Incorporated technique with PVDs has been used for dewatering from fine-grained soils for the purpose of ground improvement by means of prefabricated vertical drain systems. The laboratory model tests were performed by using the flushing tracer solutions for silty soils and recorded the tracer concentration changes with the elapsed time and flow rates. The modeling was intended to predict the effectiveness and time dependence of the remediation process. Modeling has been performed on the extraction, considering tracer concentration and laboratory model test characteristics. The computer model used herein are SEEP/W and CTRAN/W, this 2-D finite element program allows for modeling to determine hydraulic head and pore water pressure distribution, efficiency of remediation for the subsurface environment. It is concluded that the coefficient of permeability of contaminated soil is related with vertical velocity and extracted flow rate. The vertical velocity and extracted flow rate have an effect on dispersivity and finally are played an important role in-situ soil remediation.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.4
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• pp.323-332
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• 2019

Non-curable rubberized polymer asphalt waterproof coating materials in Korea and China are manufactured without advanced quality control techniques and common standard, And they are exposed consistent water leakage problems. Import and application of Korean waterproofing products and installation methods is difficult in the present situation as the Chinese standard(JC/T 2428) is different in nature with the Korean counterpart products, And quality assurance is inevitable based on mutual standards. In order to resolve this issue, alternatives such as using standards provided by the ISO (International Organization for Standardization) are generally employed, but there is no such ISO standard as a waterproof material for non-curable rubberized polymer asphalt material. Furthermore, it is unreasonable to develop the ISO standard for rubber asphalt seals for exchange in terms of time and cost. This study proposes that the establishment of a quality standard that can be applied for both countries will be required via an joint international standard that outlines the properties of materials if applied in mutual trade exchange.

• Journal of Korean Society for Geospatial Information Science
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• v.24 no.1
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• pp.81-87
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• 2016

It is important to analyze the exact damage information for fast recovery when natural disasters cause damage on river-side facilities such as dams, bridges, embankments etc. In this study, we shows the method to effectively damage analysis plan using UAV(Unmanned aerial vehicle) images and accuracy assessment of it. The UAV images are captured on area near the river-side facilities and the core methodology for damage analysis are image matching and change detection algorithm. The result(point cloud) from image matching is to construct 3-dimensional data using by 2-dimensional images, it extracts damage areas by comparing the height values on same area with reference data. The results are tested absolute locational precision compared by post-processed aerial LiDAR data named reference data. The assessment analysis test shows our matching results 10-20 centimeter level precision if external orientation parameters are very accurate. This study shows suggested method is very useful for damage analysis in a large size structure like river-side facilities. But the complexity building can't apply this method, it need to the other method for damage analysis.

• The KIPS Transactions:PartD
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• v.18D no.4
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• pp.261-274
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• 2011

In recent competitive business environment each enterprise has to be agile and flexible. For these purposes run-time monitoring ofservices provided by an enterprise and early decision making through this becomes core competition of the enterprise. In addition, in order to process various innumerable events which are generated on enterprise systems techniques which make filtering of meaningful data are needed. However, the existing study related with this is nothing but discovering of service faults by monitoring depending upon API of BPEL engine or middleware, or is nothing but processing of simple events based on low-level events. Accordingly, there would be limitations to provide useful business information. In this paper, through situation detection an extended complex event model is presented, which is possible to provide more valuable and useful business information. Concretely, first of all an event processing architecture in an enterprise system is proposed, and event meta-model which is suitable to the proposed architecture is going to be defined. Based on the defined meta-model, It is presented that syntax and semantics of constructs in our event processing language including various and progressive event operators, complex event pattern, key, etc. In addition, an event context mechanism is proposed to analyze more delicate events. Finally, through application studies application possibility of this study would be shown and merits of this event model would be present through comparison with other event model.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.9A
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• pp.1290-1298
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• 2000

Turbo Code decoder is an iterate decoding technology, which extracts extrinsic information from the bit to be decoded by calculating both forward and backward metrics, and uses the information to the next decoding step Turbo Code shows excellent performance, approaching Shannon Limit at the view of BER, when the size of Interleaver is big and iterate decoding is run enough. But it has the problems which are increased complexity and delay and difficulty of real-time processing due to Interleaver and iterate decoding. In this paper, it is analyzed that MAP(maximum a posteriori) algorithm which is used as one of Turbo Code decoding, and the factor which determines its performance. MAP algorithm proceeds iterate decoding by determining soft decision value through the environment and transition probability between all adjacent bits and received symbols. Therefore, to improve the performance of MAP algorithm, the trust between adjacent received symbols must be ensured. However, MAP algorithm itself, can not do any action for ensuring so the conclusion is that it is needed more algorithm, so to decrease iterate decoding. Consequently, MAP algorithm and Turbo Code performance are analyzed in the nongaussian channel applying Robust equalization technique in order to input more trusted information into MAP algorithm for the received symbols.

• Horticultural Science & Technology
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• v.19 no.1
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• pp.81-86
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• 2001

This experiment was carried out to investigate watering with relation to growth, quality and yield of essential oil in sweet basil. The degree of water stress was taken as amount of watering. D1 was watered with 25mL for 2 weeks and 30mL from 4 to 5 weeks after planting in Wagner pot (1/20000a, ${\phi}24cm$). As this, 75mL and 90mL, 225mL and 270mL, and 675mL and 810mL were watered in D2, D3, and D4 treatment respectively. DFT was set up as water stress was not inflicted. The growth of basil in D3 and D4 was better than that of others, in which root activity was as much twice as that of D1. Essential oil of D1 was recorded the lowest content as 0.33%. The result of proline content, peroxidase activity, photosynthesis, stomatal conductance and stomatal resistance were proved D1 to be stressed. This treatment consequently increased the content of essential oil. In consideration of growth and essential oil content, D3 treatment was highest as 47.37mg in oil production per plant. Finally, D3 watered with 225mL for 2 weeks and 275mL from 4 to 5 weeks after planting could be selected on the purpose of both plant growth and essential oil production. Essential oil content of sweet basil was increased in response to water stress. For increase of essential oil yield, oil synthesis could be raised by giving water stress just before harvesting.

• Journal of KIISE:Information Networking
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• v.33 no.6
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• pp.407-419
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• 2006

As substituting IPv6 network for all IPv4 network in a short time seems unattainable due to high cost and technical limitation, IPv4 and IPv6 are expected to coexist for a certain period of time. Under the co]existing environment of IPv4 and IPv6, interworking brings a number of extra security considerations even if it may have no security problem for each protocol respectively. Thus, the analysis and solutions for those various attacks toward IPv4/IPv6 interworking-related security are inevitably required for the sake of effective transition and settlement to IPv6. In this paper we carried out a proper rule of packet filtering for IPv6-in-IPv4 tunneling interworking environment to protect the IPv4/IPv6 interworking-related security attacks. Design and implementation of the packet filtering system suitable for IPv4/IPv6 tunneling environment in the form of Linux netfilter and ip6tables are also shown. Thru this study, the packet filtering system was found operating correctly ill the tunneling mechanism.

• Current Research on Agriculture and Life Sciences
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• v.22
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• pp.19-27
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• 2004

Cultivation area of garlics is 9% of all cultivation area of vegetables. The amount of annual demand is increased in 1,000~1,500ton. Also, the amount of demand per person has a tendency to increase as above 10kg. So, garlics has become important crops in agriculture. The purpose of this study is to acquire the basic information to design the garlic seeder attached power tiller. We used Working Model 3D program to design an automatic aligning device which is the most important part of the garlic seeder. The results are as follows; 1. The optimum depth of garlics seeding was shown as 3cm. 2. The garlic seed has to he discharged from the garlic seeder at intervals of 0.75sec in order to seed at intervals of seeds of 15cm. 3. The optimum design factors of the automatic aligning device were shown as cylinder diameter of 4cm, cylinder gap of 1cm, revolution of 36rpm and inclined angle of cylinder of $8.4^{\circ}$.