• Environmental Engineering Research
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• v.22 no.4
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• pp.393-400
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• 2017

One of the big problems facing municipalities is the management and control of urban flooding where urban drainage systems are under growing pressure due to increases in urbanization, population and changes in the climate. Urban flooding causes environmental and infrastructure damage, especially to roads, this damage increasing maintenance costs. The aim of the present study is to develop a decision support tool to identify the performance of storm networks to address future risks associated with climate change in the Middle East region and specifically, illegal sewer connections in the storm networks of Karbala city, Iraq. The storm water management model has been used to simulate Karbala's storm drainage network using continuous hourly rainfall intensity data from 2008 to 2016. The results indicate that the system is sufficient as designed before consideration of extra sewage due to an illegal sewer connection. Due to climate changes in recent years, rainfall intensity has increased reaching 33.54 mm/h, this change led to flooding in 47% of manholes. Illegal sewage will increase flooding in the storm system at this rainfall intensity from between 39% to 52%.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.5
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• pp.563-573
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• 2015

For hard rock subsea tunnels the most challenging rock mass conditions are in most cases represented by major faults/weakness zones. Poor stability weakness zones with large water inflow can be particularly problematic. At the pre-construction investigation stage, geological and engineering geological mapping, refraction seismic investigation and core drilling are the most important methods for identifying potentially adverse rock mass conditions. During excavation, continuous engineering geological mapping and probe drilling ahead of the face are carried out, and for the most recent Norwegian subsea tunnel projects, MWD (Measurement While Drilling) has also been used. During excavation, grouting ahead of the tunnel face is carried out whenever required according to the results from probe drilling. Sealing of water inflow by pre-grouting is particularly important before tunnelling into a section of poor rock mass quality. When excavating through weakness zones, a special methodology is normally applied, including spiling bolts, short blast round lengths and installation of reinforced sprayed concrete arches close to the face. The basic aspects of investigation, support and tunnelling for major weakness zones are discussed in this paper and illustrated by cases representing two very challenging projects which were recently completed (Atlantic Ocean tunnel and T-connection), one which is under construction (Ryfast) and one which is planned to be built in the near future (Rogfast).

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12A
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• pp.1177-1181
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• 2006

In this paper, we proposed the new wavelength tunable filter for wide tunability of fiber ring laser. The proposed filter consists of the cascaded connection of Fiber Reflection Mach-Zehnder Interferometer and Sagnac filter or of hybrid filter and fiber Reflection Mach-Zehnder Interferometer. The simulation shows that the continuous tunable range of 50nm can be obtained and that more stable single mode operation of ring laser can be expected due to narrow FWHM. of filter spectrum.

• Korean Journal of Computational Design and Engineering
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• v.12 no.2
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• pp.118-125
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• 2007

Designer has recently required the supporting system to assist the design steps that are not simple and standardized. But, as it is often the case with many researches, the design support systems have the problems that the functional module's expansion and the flexible connection with the intelligent CAD System are insufficient. In this paper, we present a framework, EDSS Frame (Expanded Design Support System Frame) to improve in its problems. For the implementation of the EDSS Frame, we make the functional modules, the executable files and analyze a characteristic of the functional modules. Finally, we checked the cases that is generated. Through these works, we organize the algorithm of the running process in each cases. A user can make the process through the association of the functional modules. Also, we make the DLL files or algorithms for corresponding in change of the intelligent CAD System. User can make the additional file or algorithm for a new release of the intelligent CAD system. EDSS Frame can be used for the implementation of the design support system on a various fields, and assists a designer with the rapid reconstruction of the design support system through the continuous addition of the functional modules and the redefinition of the running process between the functional modules.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.768-776
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• 2006

Recently in spite of Development of Investigation machine, in Application of Geotechnical Properties by empirical recommendation to the Slope Stability Analysis. It is generally Application of convenience and conservative Geotechnical Properties by Borehole Shear Test(BST) in Representative Zone that Non-Division of Increase as the depth of Strength Parameters In Deep Weathered Zone. Therefore, it is become environment pollution and Non-Economical Slope Design to Application of convenience and conservative Geotechnical Properties. The production mechanism of Deep Weathered Zone is tend to Weathering Degree low and Strength increase by increase as the depth. it is realistic design that Division of Deep Weathered Zone and application Geotechnical Properties of Each Layer. In this Paper, Determined The Relationship of Strength Parameters between Standard Penetration Test(SPT), Borehole Shear Test(BST) and empirical recommendation also Applyed each strength parameters of divided zone to the Slope Stability Analysis by continuous Borehole Shear Test(BST) in Deep Weathered Zone during design of The 2nd Bridge Connection Road of Incheon International Airport.

• Journal of Families and Better Life
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• v.25 no.3 s.87
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• pp.151-168
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• 2007

The purpose of this study was to investigate the causal relationship of kindergarteners' alphabet knowledge to their ability to read words, in connection with the features of the Korean alphabet 'Hangul'. A total of 289 children aged four to six from three kindergartens in Busan participated in the study. The main results are as follows. To begin with, the participants showed continuous development in the knowledge of consonant names, vowel sounds, the vowel stroke-adding principle, and the alphabet composition principle. Meanwhile, discontinuous development was found in the knowledge of consonant sounds and the consonant stroke-adding principle, which indicated that kindergartners could show differential speed in various sub-skills of literacy development. The kindergartners' naming of consonants developed before their recall of consonant sounds, and the knowledge of consonant sounds had an effect on the knowledge of vowel sounds. Children had difficulty in treating more complicated letters of the alphabet stroke-adding principle test, and eve syllables of the alphabet composition principle test. Most importantly, the children's alphabet knowledge was strongly related to their ability to read words written in Hangul, as kindergarteners with a greater knowledge of alphabet names, sounds, and principles were shown to read words better.

• Progress in Superconductivity and Cryogenics
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• v.14 no.2
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• pp.20-23
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• 2012

With continuous development of the 2nd generation HTS conductor, the critical current of the conductor is also increasing. However, many applications require more than 2 conductors in parallel to transport large current. Applications such as HTS power cables and some HTS current leads usually need much larger transport current than that provided by a single conductor and they require more than several tens of HTS conductors. In the case of parallel connection of multiple HTS conductors, the current distribution depends on the contact resistance of each conductor at the terminals for DC operation. The non-uniform distribution of the terminal resistances results in a non-uniform distribution of the current. The resultant current non-uniformity affects on the measurement of the I-V curve and the thermal performance of the multiple conductors. This paper describes the I-V curves obtained from multiply connected HTS conductors with different terminal contact resistances to investigate the relationship between the distorted I-V curve and heat generation.

• Journal of the Korean Society of Safety
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• v.21 no.6 s.78
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• pp.106-115
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• 2006

The purpose of this study is to provide basic data for continuing study in order to accomplish preventive countermeasures for work-related musculoskeletal disorders(WMSD) and to examine related factors in connection with each other as: the working environment, the equipment used, working method, pain symptoms of dentists. The investigation period for this study was from November 1, 2004 to February 28, 2005, and we analyzed questionnaire survey of 190 dentists who were giving medical treatment in and around the metropolitan area and Daegu City. Also, we visited 20 dental hospitals personally and examined the work posture through check lists, interviews, and field investigations on work posture using photos and videotaping. This study showed the increasing physical burdens which were related to dentists work accomplishment and attitude, recognizing pain which were affecting work related WMSD. With the access of ergonomics and improving the education and training of awkward medical treatment methods and posture, and continuous public information about WMSD, the occurrence rate of WMSD could be decreased.

• Journal of the Korean Society of Safety
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• v.31 no.1
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• pp.74-80
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• 2016

In this paper, structural characteristics for an extradosed prestressed concrete box girder bridge are investigated in terms of selective parameters. These parameters are mainly associated with the structural details of the extradosed bridge and derived from currently available literatures regarding previous design drawings. The analyses have been carried out using general-purpose structural analysis program, RM-Space Frame. The parameters evaluated for the present study represent the most salient features of the extradosed bridge and are as follows; 1) span length ratio(side-span length to center-span length), 2) boundary condition of girder, 3) height of pylon, 4) anchorage location of external cables and 5) girder stiffness. The analytical predictions indicate that span length ratio and pylon height are reasonably adequate in the range of 0.55 to 0.60 and $L_m/8$ to $L_m/12$ respectively for the bridge under consideration. Also, demonstrated is the boundary condition of girder, in which rigid-connection details give more efficiency than the continuous details. In addition, considering structural characteristics of the extradosed bridge, it is desirable that the girder stiffness should be determined by the stress range of external cables rather than bending moment of girder.

• Steel and Composite Structures
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• v.26 no.5
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• pp.595-606
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• 2018

A calculation method was presented to calculate the deflection of GFRP-concrete-steel beams with full or partial shear connections. First, the sectional analysis method was improved by considering concrete nonlinearity and shear connection stiffness variation along the beam direction. Then the equivalent slip strain was used to take into consideration of variable cross-sections. Experiments and nonlinear finite element analysis were performed to validate the calculation method. The experimental results showed the deflection of composite beams could be accurately predicted by using the theoretical model or the finite element simulation. Furthermore, more finite element models were established to verify the accuracy of the theoretical model, which included different GFRP plates and different numbers of shear connectors. The theoretical results agreed well with the numerical results. In addition, parametric studies using theoretical method were also performed to find out the effect of parameters on the deflection. Based on the parametric studies, a simplified calculation formula of GFRP-concrete-steel composite beam was exhibited. In general, the calculation method could provide a more accurate theoretical result without complex finite element simulation, and serve for the further study of continuous GFRP-concrete-steel composite beams.