• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.90-93
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• 2003

The most common deteriorating processes of concrete structures in the world-wide are carbonation and chloride ion. In this paper, chloride profiles of carbonated concrete is predicted to considering two layer composite model, which is based on Fick's 2nd law. From the experimental result on combined deterioration of chloride and carbonation, it was examined that high chloride concentration was built up to 3-5㎜ over depth from carbonation depth. The analytical modeling of chloride diffusion, which was based on the Fick's 2nd law of diffusion, was suggested to depict the relative influence of the carbonation depth.

• Proceedings of the Korean Vacuum Society Conference
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• 1998.02a
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• pp.129-129
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• 1998

Most of the surface/interface analysis tools have limited depth profiling c capability in terms of the profiling range and the depth resolution. However, M MEIS can profile the surface and subsurface composition and structure q quantitatively and non-destructively with atomic layer depth resolution. I In this presentation, the MEIS system developed at KRISS will be briefly d described with an introduction on the principle of MEIS. Recent MEIS r results on the surface and interface composition and structural change due to i ion bombardment will be presented for preferential sputtering of T:없Os and d damage depth profiles of SHooD, Pt(l11), and Cu(l1D due to Ar+ ion b bombardment. Direct observation of strained Si lattices and its distribution i in the SHool)-SiCh interface and the initial stage of Co growth on Pt(l11) w will be reported. H surfactant effects on epitaxial growth of Ge on Si(ooD w will be discussed with STM results from SND.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.6
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• pp.63-70
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• 1989

The ion beam extracted from the AuGe liquid metal ion source was implanted into GaAs substrate. The surface composition and the structure of ion implanted samples were investigated by AES, RHEED, SEM and EPMA. The depth profiles measured by AES were compared with the results of Monte Carlo simulation based on the two-body collision. As the results of AuGe ion implantation the preferential sputtering of As were revealed by AES and EPMA, and the outdiffusion of Ga and Ge was investigated by 300$^{circ}C$ annealing. The Au and Ge depth profiles measured by AES agreed with the results of Monte Carlo simulation based on the two-body collision.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.8
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• pp.1222-1229
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• 2010

Compared to conventional high resolution acoustic profiling, ultra high resolution shallow acoustic profiling using parametric echo sounder is limited in penetration, yet it provides resolution suitable for detailed seabed investigation in the shallow waters. The parametric sub-bottom profiler system provides not only the exact determination of water depth, but also the detailed information about sediment layers and sub-bottom structures. Possible applications include dredging project, search of buried pipeline, ship wrecks, and other artificial objects through the detailed mapping of thickness and structure of the upper sedimentary layers. In this study, contaminated sediments were discriminated by the correlation of ultra high resolution profiles with geologic data. In addition, the burial depth of the submarine cable was measured by the interpretation of acoustic anomalies in the profiles.

• Journal of Mechanical Science and Technology
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• v.20 no.3
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• pp.335-344
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• 2006

A comprehensive review of through thickness transverse residual stress distributions in a range of as-welded and mechanically bent components made up of a range of steels has been carried out, and simplified generic transverse residual stress profiles for a plate and pipe components have been proposed. The geometries consisted of welded pipe butt joints, T-plate joints, tubular T-joints, tubular Y-joints and a pipe on plate joints as well as cold bent tubes and pipes. The collected data covered a range of engineering steels including ferritic, austenitic, C-Mn and Cr-Mo steels. Measured residual stress data, normalised with respect to the parent material yield stress, has shown a good linear correlation versus the normalised depth of the region containing the residual stress resulting from the welding or cold-bending process. The proposed simplified generic residual stress profiles based on the mean statistical linear fit of all the data provides a reasonably conservative prediction of the stress intensity factors. Whereas the profiles for the assessment procedures are fixed and case specific, the simple bilinear profiles for the residual stresses obtained by shifting the mean and bending stress from the mean regression line have been proposed and validated.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1996.04a
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• pp.26-26
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• 1996

• Progress in Medical Physics
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• v.33 no.4
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• pp.150-157
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• 2022

Purpose: Elekta synergy^® was commissioned in the Seoul National University Veterinary Medical Teaching Hospital. Recently, Chung-Ang University Gwang Myeong Hospital commissioned Elekta Versa HD^TM. The beam characteristics of both machines are similar because of the same Agility^TM MLC Model. We compared measured beam data calculated using the Elekta treatment planning system, Monaco^®, for each institute. Methods: Beam of the commissioning Elekta linear accelerator were measured in two independent institutes. After installing the beam model based on the measured beam data into the Monaco^®, Monte Carlo (MC) simulation data were generated, mimicking the beam data in a virtual water phantom. Measured beam data were compared with the calculated data, and their similarity was quantitatively evaluated by the gamma analysis. Results: We compared the percent depth dose (PDD) and off-axis profiles of 6 MV photon and 6 MeV electron beams with MC calculation. With a 3%/3 mm gamma criterion, the photon PDD and profiles showed 100% gamma passing rates except for one inplane profile at 10 cm depth from VMTH. Gamma analysis of the measured photon beam off-axis profiles between the two institutes showed 100% agreement. The electron beams also indicated 100% agreement in PDD distributions. However, the gamma passing rates of the off-axis profiles were 91%-100% with a 3%/3 mm gamma criterion. Conclusions: The beam and their comparison with MC calculation for each institute showed good performance. Although the measuring tools were orthogonal, no significant difference was found.

• The Plant Pathology Journal
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• v.26 no.1
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• pp.90-92
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• 2010

Staining profiles and bacterial morphology were compared in Xanthomonas citri pv. citri by a transmission electron microscopy. Four types of negative staining regimes were employed depending on culture media and heavy metal stains. The bacterial cells grown on LB agar media often appeared clustered on the supporting film. Meanwhile, individual bacterial cells could be readily found on the preparations from LB broth media. Typical rod-shaped cells (ca. $1\;{\mu}m$ in length) and their flagella were observed in either 2% uranyl acetate (UA) or 2% neutralized potassium phosphotungstate (PTA) staining. The UA-stained bacteria often showed relatively intact cell morphology and rather positively stained cells with a thin electron-dense stain depth around bacteria. The PTA-stained bacteria were characterized by the wrinkled cell surface where the stain was entrapped in grooves. In addition, distinct electron-dense stain depth was evident around the PTA-stained preparations. Numerous fimbriae could be mostly observed from the PTA-stained preparations of the two culture media, but not from the UA-stained preparations.

• Korean Journal of Optics and Photonics
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• v.9 no.2
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• pp.86-91
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• 1998

Multimode planar waveguides have been fabricated by an electric-field assisted ion exchange in soda-lime glass substrates. Measurements of the mode indices have been made and the index profiles modeled on modified Fermi function are explained by a comparative analysis with the concentration profiles obtained using an electron probe X-ray micro analyzer. The analytical measurements showed that no more than 95% of sodium ions were replaced by the cesium ions. We established formulas for guide depth, mobility, and refractive index change, given the applied electric field, the diffusion temperature, and the time. We have verified the linear relations in the formulas not only between guide and root of diffusion time but also between guide depth and the applied electric filed experimentally.

• Asian Journal of Atmospheric Environment
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• v.10 no.1
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• pp.13-21
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• 2016

The vertical distributions of aerosol extinction coefficient were estimated using the scaling height retrieved at Gwangju, Korea ($35.23^{\circ}N$, $126.84^{\circ}E$) during a spring season (March to May) of 2009. The aerosol scaling heights were calculated on a basis of the aerosol optical depth (AOD) and the surface visibilities. During the observation period, the scaling heights varied between 3.55 km and 0.39 km. The retrieved vertical profiles of extinction coefficient from these scaling heights were compared with extinction profile derived from the Light Detection and Ranging (LIDAR) observation. The retrieve vertical profiles of aerosol extinction coefficient were categorized into three classes according to the values of AODs and the surface visibilities: (Case I) the AODs and the surface visibilities are measured as both high, (Case II) the AODs and the surface visibilities are both lower, and (Others) the others. The averaged scaling heights for the three cases were $3.09{\pm}0.46km$, $0.82{\pm}0.27km$, and $1.46{\pm}0.57km$, respectively. For Case I, differences between the vertical profile retrieved from the scaling height and the LIDAR observation was highest. Because aerosols in Case I are considered as dust-dominant, uplifted dust above planetary boundary layer (PBL) was influenced this discrepancy. However, for the Case II and other cases, the modelled vertical aerosol extinction profiles from the scaling heights are in good agreement with the results from the LIDAR observation. Although limitation in the current modelling of vertical structure of aerosols exists for aerosol layers above PBL, the results are promising to assess aerosol profile without high-cost instruments.