• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.453-456
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• 2004

RC frames built prior to the advent of the philosophy of ductile concrete is one type of existing construction susceptible to damage. Strengthening and stiffening of such frames has been accomplished by infilled frames with cast-in-place, reinforced concrete walls. Placement of CIP shear walls within strategic bays of a structure appears to be a logical and economical method to strengthen a reinforced concrete frame and to stiffen a building in order to reduce architectural and mechanical damage. This study investigates the seismic performance of cast-in place infilled shear wall within existing frames. The object of this study is to clarify the seismic capacity and characteristics in the hysteretic behavior of bare frame, CIP infilled shear wall and CIP infilled wall reinforced diagonal bars.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.5
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• pp.106-113
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• 2004

The eddy current brake system is a non-contact brake based on the mutual relation between the rail and the frame. Consequently, the accuracy is required in estimating the stress concentration and the deformation of the eddy current brake system. In this paper, the static analysis considering the gravity and the suction force for the deformation and the stress concentration of the main frame of the initially designed eddy current brake system was carried out. The shape of the I-type beam obtained from the optimization was analyzed and compared with the initial model. Also, the initial model was modified based on the optimization model and the result was verified to have the acceptable improvement.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.4
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• pp.527-532
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• 2014

Purpose: The matching of the optical center and the pupil center was measured by photographs in wearing glasses. In this study, the influences of the induced prism by the mismatching are studied. Methods: 74 subjects (148 eyes) who were spectacles wearer were participated in this study. The mean age was $29.19{\pm}12.22$ years (range 19-55 years). The facial photographs of subjects were taken while wearing spectacles. The matching of the corneal reflected image and optical center of the spectacle lens in the horizontal deviations, and the vertical deviations were measured by the observation of the photo image. The prisms induced in accordance with various frame type were calculated from the mismatching deviations. Results: The binocular horizontal deviations were $1.55{\pm}1.70mm$ for the metal frame, $1.71{\pm}2.21mm$ for the clings type plastic frame, and $1.15{\pm}1.38mm$ for the plastic frame. In the horizontal direction induced prism, the ratio over the tolerance was 23%. The ratio were the 17.6% at the BI prism, and 5.4% at the BO prism. The binocular vertical deviation comparisons were $3.93{\pm}1.91mm$ for the metal frame, $5.79{\pm}1.93mm$ for the clings type plastic frame, and 1$6.01{\pm}2.94mm$ for the plastic frame. In the vertical direction induced prism, the ratio over the tolerance was 44.6%. Based on the refraction power, the ratio were 12.2% at -0.25${\leq}-3.00$, and 32.4% at -3.00${\leq}-12.00D$. Conclusions: The induced prisms in the horizontal direction were much in the BI prism. The binocular vertical deviations of the glasses.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.487-492
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• 1999

The purpose of this study to find the mixture of concrete for Top-Down method. Throughout test of elapsed time change and L-type flow, it was proposed basic performance and level of top-down method concrete. When change as to elapsed time is considered, so series of F10 added 10% S.P satisfied slump and demanded flow (60$\pm$5cm), and L-type slump, L-type flow satisfied liquidity, it can be considered basic mixture of designed actual frame later.

• Proceedings of the KSR Conference
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• 2000.05a
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• pp.455-462
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• 2000

The characteristic of “Korea LRT Carbody” is designed by using AED(All Extrusion Design) method. This is developed in Europe and be introduced in this paper minutely. The window type of “Korea LTR” has no supported frame, so the passengers ensure the outside view widely. The passenger's door will designed by plug type - This is the first time in Korea. In this report we have an object to the strength analysis for the carbody design. For the purpose of safety and lightening, we are going to research the section of thickness through optimization design.

• Tunnel and Underground Space
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• v.28 no.3
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• pp.258-276
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• 2018

The accurate and quantitative ground information on the hydraulic conductivity characteristics of rock mass is one of the key factors for evaluation of the hydro-geological behaviour of rock mass around an excavated opening under high water pressure. For tunnel and rock structures in seabed, where the sea acts as an infinite source of water, its importance become greater with increasing construction depth below sea level. In this study, to improve the problems related with poor system configuration and incorrect data acquisition of previous hydraulic packer testing equipment, we newly developed an integrated main frame and 30 bar level waterproof downhole sonde apparatus, which were optimized for deep hydraulic packer test in seabed rock mass. Integration of individual test equipment into one frame allows safe and efficient field testing work on a narrow offshore drilling platform. For the integrated type main frame, it is possible to make precise stepwise control of downhole net injection pressure at intervals of $2.0kg_f/cm^2$ or less with dual hydraulic oil volume controller. To ensure the system performance and the operational stability of the prototype mainframe and downhole sonde apparatus, the field feasibility tests were completed in two research boreholes, and using the developed apparatus, the REV(Representative Elementary Volume) scale deep hydraulic packer tests were successfully carried out at a borehole located in the basalt region, Jeju. In this paper, the characteristics of the new testing apparatus are briefly introduced and also some results from the laboratory and in-situ performance tests are shown.

• Journal of the Korean Society of Safety
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• v.21 no.4 s.76
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• pp.102-107
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• 2006

Construction accidents have not decreased in spite of much effort such as new work methods, education and research related to safety works. Specially, many fatal accidents happened in construction works which involve the apartment, building, school, church, hotel, hospital, bank work and the other works. These accidents are mainly caused by unanticipated risk factors. From these reasons, this study researched fatal accidents which happened in construction works during last 13 years($1992{\sim}2004$) and analyzed the input workers and a work period of construction work. According to the input workers and a work period, the results are as following. During 13years($1992{\sim}2004$), the fatal accidents, related to the construction work, were happened to the 1,977 cases. These results were occupied the 21.32% of the total industry accidents. According to the result of the construction, the fatal accident rate of a concrete form work was the highest rate of 16.24% (321 cases) and a temporary work, a steel frame work was the each rate of 12.39%(245 cases), 10.07%(199 cases). Comparing to other work types, the fatal accident rate of those three work types(concrete form work, temporary work, steel work) was represented highly. We surveyed input workers and work period of construction work site. From the result of survey, input workers of a concrete form work were occupied with 13,720. The risk rate of the work type, which was considered input workers and work period, was represented 0.3622(a steel frame work), 0.1142(a temporary work), 0.0782(a tower crane) and 0.0772(a concrete work).

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.39 no.3
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• pp.125-131
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• 2002

In this paper, a new concatenation scheme of serial concatenated convolutional codes is proposed and the performance analyzed. In the proposed scheme, each of information and parity bits of outer code is entered into inner code through interleaver and deinterleaver. Therefore, the interleaver size is same as the length of input frame. Since the interleaver size of proposed type is reduced to half of the conventional Benedetto type, the interleaver delay time required for iterative decoding is reduced. In addition the multiplexer and demultiplexer are not used in the decoder of the proposed type, the complexity of decoder can be also reduced. As results of simulation, the performance of proposed type shows the better error performance as compared to that of the conventional Benedetto type in case of the same interleaver size. And it can be observed that the difference of BER performance is increased with the increase of Eb/No. In case of the same length of input frame, the proposed type shows almost same performance with Benedetto type despite that the interleaver size is reduced by half.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.11
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• pp.117-128
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• 2019

The necessity of the Toi-Maru has increased greatly in order to enter to the building or to move conveniently in the building after the mid-Joseon period, when the combination of On-dol Ma-ru began to be universally used. According to this process, the 3-Dori type upper structure is thought to have undergone the typological changed by securing a more stable space of Toi-Maru In cases where a relatively large girder was used, it is often the case that the space is divided using a pillar to place a Toi-Maru on the front. However, it is difficult to find a case where the width of the Toi-Maru exceeds 1meter due to its structural limit. The type that made additional Toi-girder to overcome the spatial constraint of this structure and replaced the method of former typology after Mid-Jpseon period. In case of 5-Dori type, Toi-Maru installed in between high post and Toi post in early period. In these type, the width of Toi-Maru was subordinated by the location of milled Dori of roof structure and sometimes it became too excessive. 5-Dori type with Pyon-ju occurred to overcome these restriction between the width of Toi-Maru and the location of milled Dori of roof structure. Not a few remains of Mid-Jpseon period keeping the evidences of changing process of roof structure provoked by Toi-Maru installation. The consistent process of Toi-Maru installation and structural adjustment will be focused to consider the attempt to spatial requirement and architectural reaction in Mid-Joseon perid.

• Journal of Environmental Science International
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• v.10 no.1
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• pp.35-39
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• 2001

The mutagenicity of the river water of Nakdong river estuary was determined by Ames test using the blue rayon suspension method. Samples were collected from 10 sites in the estuary once in each season of 1998. The samples collected from the sites where industrial waste discharge on May were mutagenic, but the other samples were not mutagenic. The sample collected from the site 1 located near the industrial area (Hadan-dong) were highly mutagenic in the TA98 with (+S9) and without (-S9) mix as well as in the TA100 with (+S9) and without (-S9) S9 mix, suggesting that the river water of this site is polluted by direct and indirect mutagens of frame-shift type as well as direct and indirect mutagens of base-replacement type. The positive mutagenicity, although relatively low, was also detected in TA98 with (+S9) and without (-S9) S9 mix in the extract of the site 4 near the industrial area(Jangrim-dong), suggesting that the primary mutation type is frame-shift. The negative mutagenicity from July to December at the sites (1-4) near the industrial area seems to be affected by the low economic growth rate in 1998 in Korea. On the other hand, the negative mutagenicity in all extracts collected from the sites 5-10 near the residential area where living sewage discharge, suggests that the river water was not polluted by mutagens.