• Title/Summary/Keyword: Pohang Korea

Search Result 1,648, Processing Time 0.029 seconds

Development of models for the prediction of electric power supply-demand and the optimal operation of power plants at iron and steel works

  • Lee, Dae-Sung;Yang, Dae-Ryook;Lee, In-Beum;Chang, Kun-Soo
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1992.10b
    • /
    • pp.106-111
    • /
    • 1992
  • In order to achieve stable and efficient use of energy at iron and steel works, a model for the prediction of supply and demand of electric power system is developed on the basis of the information on operation and particular patterns of electric power consumption. The optimal amount of electric power to be purchased and the optimal fuel allocation for the in-house electric power plants are also obtained by a mixed-integer linear programming(MILP) and a nonlinear programming (NLP) solutions, respectively. The validity and the effectiveness of the proposed model are investigated by several illustrative examples. The simulation results show the satisfactory energy saving by the optimal solution obtained through this research.

  • PDF

EPMA quantification on the chemical composition of retained austenite in a Fe-Mn-Si-C-based multi-phase steel

  • Yoon‑Uk Heo;Chang‑Gon Jeong;Soo‑Hyun Kim;Gun‑Young Yoon;T. T. T. Trang;Youngyun Woo;Eun Yoo Yoon;Young‑Seon Lee
    • Applied Microscopy
    • /
    • v.52
    • /
    • pp.14.1-14.10
    • /
    • 2022
  • An electron probe X-ray microanalyzer (EPMA) is an essential tool for studying chemical composition distribution in the microstructure. Quantifying chemical composition using standard specimens is commonly used to determine the composition of individual phases. However, the local difference in chemical composition in the standard specimens brings the deviation of the quantified composition from the actual one. This study introduces how to overcome the error of quantification in EPMA in the practical aspect. The obtained results are applied to evaluate the chemical com position of retained austenite in multi-phase steel. Film-type austenite shows higher carbon content than blocky-type one. The measured carbon contents of the retained austenite show good coherency with the calculated value from the X-ray diffraction.

Molecular Dynamics of the C-Terminal Domain Mouse CDT1 Protein

  • Khayrutdinov, Bulat I.;Bae, Won-Jin;Kim, Jeong-Ju;Hwang, Eun-Ha;Yun, Young-Mi;Ryu, Kyoung-Seok;Cheong, Hae-Kap;Kim, Yu-Gene;Cho, Yun-Je;Jeon, Young-Ho;Cheong, Chae-Joon
    • Journal of the Korean Magnetic Resonance Society
    • /
    • v.11 no.1
    • /
    • pp.30-41
    • /
    • 2007
  • The backbone molecular dynamics of the C-terminal part of the mouse Cdt1 protein (tCdt1, residues 420-557) was studied by high field NMR spectroscopy. The Secondary structure of this protein was suggested by analyzing of chemical shift of backbone atoms with programs TALOS and PECAN, together with NOE connectivities from 3D $^{15}N-HSQC-NOESY$ data. Measurement of dynamic parameters $T_1,\;T_2$ and NOE and limited proteolysis experiment provided information for domain organization of tCdt1(420-557). Analysis of the experimental data showed that the C-terminal part of the tCdt1 has well folded domain for residues 455-553. The residues 420-453 including ${\alpha}-helix$ (432-441) are flexible and probably belong to other functional domain in intact full length Cdt1 protein.

  • PDF

Emission Plasma Spectroscopy of High-pressure Microdischarges

  • Lee, Byeong-Jun;Ju, Yeong-Do;Kim, Seung-Hwan;Ha, Tae-Gyun;Gong, Hyeong-Seop;Park, Yong-Jeong;Park, Jong-Do;Nam, Sang-Hun
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2014.02a
    • /
    • pp.253.2-253.2
    • /
    • 2014
  • Micro hollow cathode discharges (MHCDs) are high-pressure, non-equilibrium discharges. Those MHCDs are useful to produce an excimer radiation. A major advantage of excimer sources is their high internal efficiency which may reach values up to 40% when operated under optimum conditions. To produce strong excimer radiation, the optimisation of the discharge conditions however needs a detailed knowledge of the properties of the discharge plasma itself. The electron density and temperature influence the excitation as well as plasma chemistry reactions and the gas temperature plays a major role as a significant energy loss process limiting efficiency of excimer radiation. Most of the recent spectroscopic investigations are focusing on the ultraviolet or vacuum ultraviolet range for direct detection of the excimer. In our experiments we have concentrated on investigating the micro hollow cathodes from the near UV to the near infrared (300~850 nm) to measure the basic plasma parameters using standard plasma diagnostic techniques such as stark broadening for electron density and the relative line intensity method for electron temperature. Finally, the neutral gas temperature was measured by means of the vibrational rotational structures of the second positive system of nitrogen.

  • PDF

Nondestructive, Quantitative Synchrotron Grazing Incidence X-ray Scattering Analysis of Cylindrical Nanostructure in Supported Thin Films

  • Yoon, Jin-Hwan;Yang, Seung-Yun;Lee, Byeong-Du;Joo, Won-Chul;Heo, Kyu-Young;Kim, Jin-Kon;Ree, Moon-Hor
    • Proceedings of the Polymer Society of Korea Conference
    • /
    • 2006.10a
    • /
    • pp.300-300
    • /
    • 2006
  • Nondestructive nanostructural analysis is indispensable in the development of nano-materials and nano-fabrication processes for use in nanotechnology applications. In this paper, we demonstrate for the first time a quantitative, nondestructive analysis of nanostructured thin films supported on substrates and their templated nanopores by using grazing incidence X-ray scattering and data analysis with a derived scattering theory. Our analysis disclosed that vertically oriented nanodomain cylinders had formed in 20-100 nm thick films supported on substrates consisting of a mixture of poly(styrene-b-methyl methacrylate) (PS-b-PMMA) and PMMA homopolymer, and that the PMMA nanodomains were selectively etched out by ultraviolet light exposure and a subsequent rinse with acetic acid, resulting in a structure consisting of hexagonally packed cylindrical nanopores.

  • PDF

Numerical Experiments of the Seiche in Young-il Bay and Pohang New Harbor, Korea (영일과 포항신항의 해면부진동에 관한 수치실험)

  • 박한일;정종율
    • 한국해양학회지
    • /
    • v.21 no.4
    • /
    • pp.245-258
    • /
    • 1986
  • A two-dimensional numerical model is developed to investigate the phenomenon of forced seiche caused by the incident long waves. This model is applied to Young-il Bay and Pohang New Harbor, where the seiche is most frequently observed and the damage of the seiche is serious compared with the other harbors in Korea. Some results on this study are as follows; 1. The natural periods of the first two modes obtained from the present model are about 70 and 25 minutes respectively for Young-il Bay, and about 25 and 7.5 minutes for Pohang New Harbor. These results are well consistent with those obtained by the theoretical formula, the spectral analysis, and the statistical investigation of the recorded data. 2. Since the fundamental natural period of Pohang New Harbor is almost the same as the second natural period of Young-il Bay, the seiche in Pohang New Harbor can be strongly amplified by the Oscillation in Young-il Bay. Therefore, the most strong seiche in Pohang New Harbor can occur when the long wave of about 25-minute period come into Young-il Bay.

  • PDF