• Earthquakes and Structures
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• v.17 no.6
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• pp.635-647
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• 2019

Tests and theoretical studies for seismic responses of a transmission tower-line system under coupled horizontal and tilt (CHT) ground motion were conducted. The method of obtaining the tilt component from seismic motion was based on comparisons from the Fourier spectrum of uncorrected seismic waves. The collected data were then applied in testing and theoretical analysis. Taking an actual transmission tower-line system as the prototype, shaking table tests of the scale model of a single transmission tower and towers-line systems under horizontal, tilt, and CHT ground motions were carried out. Dynamic equations under CHT ground motion were also derived. The additional P-∆ effect caused by tilt motion was considered as an equivalent horizontal lateral force, and it was added into the equations as the excitation. Test results were compared with the theoretical analysis and indicated some useful conclusions. First, the shaking table test results are consistent with the theoretical analysis from improved dynamic equations and proved its correctness. Second, the tilt component of ground motion has great influence on the seismic response of the transmission tower-line system, and the additional P-∆effect caused by the foundation tilt, not only increases the seismic response of the transmission tower-line system, but also leads to a remarkable asymmetric displacement effect. Third, for the tower-line system, transmission lines under ground motion weaken the horizontal displacement and acceleration responses of transmission towers. This weakening effect of transmission lines to the main structure, however, will be decreased with consideration of tilt component.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.594-601
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• 2021

In order to expanding of the use of steel slag, a by-product of steel industry, as a road paving construction material, this present study confirmed the possibility of the rust formation of steel slag aggregate and evaluated the durability performance and the noise reduction characteristics of asphalt concrete mixture. As a result of conducting the rust formation test of aggregate, no rust was observed in both aggregate, so it is judged that the possibility of rust formation in the actual road water environment is very low. As a result of performing the moisture resistance test, all mixtures showed a tensile strength ratio exceeding 85%, satisfied the standard as asphalt mixture. In addition, the sound absorption coefficient of the steel slag aggregate mixture was measured to be higher than that of the general aggregate mixture. Accordingly, it is speculated th at th e steel slag aggregate mixture can more effectively respond to road noise reduction than the general mixture.

• Journal of the Korea Safety Management & Science
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• v.17 no.3
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• pp.163-171
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• 2015

The aim of this study was to investigate kinematic mechanism of gait different road conditions(dry vs. oil) in order women. For this study, twenty older women and ten young women participated in this research. twelve infrared cameras were used to collect data. It appeared that the gait strategies of older women were slower velocity and higher CoM than young women. Depending on road conditions, gait velocities of dominant muscle older women on dry surface were faster than dominant sense older women, but those of them were inverse on oil surface. The slip displacement of dominant muscle older women was less than young women, but the slip displacement of dominant sense older women was greater than young women. In case of blind during stance phase on oil surface, the rotational motion of the ankle and knee joints were increased. In conclusion, older women were subjected to self-organization theory and phase shift in dynamic theory.

• Archives of Plastic Surgery
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• v.47 no.2
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• pp.146-152
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• 2020

Background Preoperative computed tomography angiography (CTA) of the abdominal wall vessels is used when planning free flap breast reconstruction (FFBR) because it provides a surgical road map which facilitates flap harvest. However, there are few reports on the effect of abnormal findings on the operative plan. Methods We conducted a retrospective study of all FFBRs performed at a tertiary referral center over a 6-year period (November 2011 to June 2017). One consultant radiologist reported on the findings. Details on patient demographics, CTA reports, and intraoperative details were collected. Results Two hundred patients received preoperative CTAs. Fourteen percent of patients (n=28) had abnormal findings. Of these findings, 18% were vascular anomalies; 36% tumorrelated and 46% were "miscellaneous." In four patients, findings subsequently prevented surgery; they comprised a mesenteric artery aneurysm, absent deep inferior epigastric (DIE) vessels, bilateral occluded DIE arteries, and significant bone metastases. Another patient had no suitable vessels for a free flap and the surgical plan converted to a pedicled transverse rectus abdominis musculocutaneous flap. The remaining incidental findings had no impact on the surgical plan or appropriateness of FFBR. More than one in 10 of those with abnormal findings went on to have further imaging before their operation. Conclusions CTA in FFBR can have a wider impact than facilitating surgical planning and reducing operative times. Incidental findings can influence the surgical plan, and in some instances, avoid doomed-to-fail and unsafe surgery. It is therefore important that these scans are reported by an experienced radiologist.

• International Journal of Highway Engineering
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• v.9 no.2 s.32
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• pp.115-127
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• 2007

Developed countries, especially in road construction and management fields, introduce new road porjects such as National Scenic Byways Program(NSBP program) in USA and the Eco-road project in Japan. This study develops a conceptual model for deploying new road projects in Korea. The four step approach is suggested to create new road projects, including foundation of an act based on the existing Road Act, creation of new road project ideas, development of evaluation process and guidelines, and enhancement of an administrative scheme. To create new road projects, three different ways are devised; (1) designation of national roads having uniqueness in overall spectrum, (2) designation of roads having intrinsic values in a different aspect, (3) designation of single structures of engineering outcomes such as bridges, tunnels, new design techniques, considerable Value Engineering output, and well analyzed Life Cycle Cost Analysis practices. For the evaluation process, NSBP program of USA and/or Sustainable City Award program of Korea would be recommended. An administrative scheme and integrated funding process for the new road projects are also suggested based on evaluation of tasks of each team or division of Korea Ministry of Construction and Transportation.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09b
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• pp.131-137
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• 2010

`Frost heave' is volumetric extension behavior of soil due to freezing. It could have a bad effect to foundations of infrastructures like building, road, railroad and bridge. Therefore, it is considered as a primary design parameter with 'adfreeze bond' and 'creep deformation' for foundation design in cold region. In some countries, studies for analyzing frost heave in many ways have being performed, however, only a few studies for evaluating frost susceptibility of soils by measuring frost heave rate of frozen soils in Korea. For analyzing frost heave as a foundation design parameter, both frost heaving rate and heaving pressure are should be addressed in study. Hence, in this study, development of experimental apparatus to evaluate frost heave and pressure is suggested.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.8
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• pp.666-667
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• 2016

The space technology road-map is under preparation as an action plan of Mid-to-Long term National Space Development Plan. To gather the capabilities of the civil researchers and to facilitate the connection between the national space plan, a special section of the journal of the Korean society for aeronautical and space sciences is arranged to introduce the core technologies of the space systems expected for the national space development plan.

• The Journal of Engineering Geology
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• v.29 no.4
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• pp.427-437
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• 2019

The purpose of this study is to improve construction cost, time, and field management when constructing a road on soft soil foundation by eliminating extra-banking of subgrade layer after completion of the consolidation process. The subgrade layer was pre-constructed before the soft ground improvement. And then it was confirmed by the field test that the compaction effect was maintained or not after consolidation settlement. As a result of the experiment, all subgrade layers were kept constant except for the top subgrade layer. So it would be advantageous to secure economical and practical in road construction if subgrade layers were constructed exclusive of the top subgrade layer.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.45-45
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• 2001

Heterocyclic aromatic amines (HCAs) are established genotoxic human cancer risks, that display their activity also in a number of animal models and in vitro. They are formed during the trying or broiling of creatinine-containing foods, mainly fish or meat. We established that mixing soy protein with ground meat blocks the formation of HCAs. we also observed that coating the surface of meat with polyphenols green or from black tea gives a dose - related reduction of the formation of HCAs.(omitted)

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.561-568
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• 2021

In this study, in order to observe the change in the amount of Tire and Road Wear Particles and the ratio of tire components in it according to the tire wear resistance performance, carried out the evaluation by varying the vulcanization reaction design of the tire tread rubber. In addition, in order to improve the reliability of the evaluation of Tire and Road Wear Particles, the evaluation was performed indoor laboratory test equipment that simulates the condition on real driving to exclude various environmental influences including minerals, driver's habits, road surface, weather, tire structure and pattern designs. After the evaluation in closed space, it is estimated that the amount of collected Tire and Road Wear Particles is 84% compared to 100% of the tire and road wear loss weight, of which 96.4~97.7% was around the road and 2.3~3.6% was in the air. As a result of analy sis of the collected Tire and Road Wear particles, the tire component existed 63~75% in the Tire and Road Wear Particles depending on the wear resistance performance of the tire.