• Korean Architects
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• v.3 no.8 s.8
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• pp.61-63
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• 1968

• Journal of the Korean Geographical Society
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• v.47 no.4
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• pp.471-473
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• 2012

This special issue is planned to introduce the recent academic state of the Korean geography, as the 32nd International Geographical Congress (IGC) in Cologne, Germany, 2012 is approaching. Korean Geographical Society successfully hosted the 29th IGC 2000 in Seoul and had a chance to introduce trends and achievements of korean geographers at the time. This issue is to review the achievements of korean geography research for the past ten years, and to overview the academic prospect of the korean geography.

• Corrosion Science and Technology
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• v.7 no.2
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• pp.92-98
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• 2008

This paper describes the experiments of the corrosion and the sliding tests of the nickel-based alloys for the gate valve seating materials used at high pressure and temperature. The general corrosion rates and IGC susceptibility are tested in pressurized water at 533 K and 575 K and in Strauss test solution. The sliding tests have been done in pressurized water at 293 k, 473 K and 573 k. The alloys containing above 10% chromium may have the anti-corrosion properties that could be applied to the valve seats for the power plants. The good sliding performance and the good pressure tightness are obtained when the disc specimens that have hardness 500 to 600 Hv combined with the seat specimens that have hardness 250 to 410 Hv containing about 40 percent of iron. The large size gate valves sliding tests have certified the test results. The anti-wear properties of the seat alloy and the anti-IGC susceptibility of the disc alloy could be improved by the addition of silicon and niobium, respectively.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.1
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• pp.15-22
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• 2009

The guidance controller of the conventional aircraft consists of inner-loop (autopilot) and outer-loop (guidance). If the guidance controller can be designed as an integrated guidance and control (IGC), the various advantages exist. The integrated guidance and control formulation can compensate for the effect of autopilot lag. An integrated approach also helps avoid the iterative procedure involved in tuning the guidance and autopilot subsystems, if designed separately. Integrated design is also less susceptible to saturation and stability problems. This paper presents an approach to IGC design for the unpowered air vehicle with the only flaperon using a combination of adaptive output feedback inversion and backstepping techniques. Adaptive neural networks are trained online with available measurements to compensate for unmodeled nonlinearities in the design process.

• Journal of the Korean institute of surface engineering
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• v.30 no.2
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• pp.144-154
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• 1997

Effects of plasma nitriding on the surface charcteristice of stainless steel(SS) were investjgated by utilizing wear tester, micro-hardness tester and potentiostat. The surface and corrosion morphology of plasma nitrided SS were analyzed by utilizing optical microscopy, SEM, XRD and WDX. It was found that plasma nitriding at $550^{\circ}C$, compared with $380^{\circ}C$, prodiced a good wear resistance and hardness as nitriding time increased, whereas Mo addition showd that were resistance and hardness decreased. Intergranular corrosion(IGC) resistance improved significantly in the case of plasma nirtrided SS containing 4.05wt% Mo at $380^{\circ}C$ because that nitrogen and Mo ast syner gidically to form a protective layer on surface which is responsible for the aggresive SCN-ion. Plasma nitrided at $550^{\circ}C$ decreased IGC as Mo content increased. Pitting improved in the plasma nitirided SS at Mo content incresased owing to retard a nucleation and growth of chromium carbide or nitirde in grain boundary.

• Applied Chemistry for Engineering
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• v.10 no.5
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• pp.718-725
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• 1999

In order to investigate the interaction characteristics of poly(dimethylsiloxane) (PDMS) with various solvents such as water, ethanol, and iso-propanol, Inverse Gas Chromatography(IGC) at finite concentration, which is a very fast, accurate, and thus promising technique in thermodynamic study of polymer systems, is employed. By measuring the specific retention volumes of the probes, the interaction parameters are calculated by means of the Flory-Huggins equation. From the results, the interaction parameters of the probes are, as expected due to the hydrophobicity of the polymer, found to be of large positive values (2$2.0{\times}10^{-3}mol/g$. For the linear PDMS, interpretation of the space distribution of molecules is performed by the Kirkwood-Buff-Zimm(KBZ) integrals, which give intuitive information about physical properties. From the KBZ integrals, water does not show the tendency of preferential solvation with the PDMS but formed self-cluster. The larger solvent molecules show a stronger tendency to distribute more randomly in the mixture.

• Journal of Powder Materials
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• v.14 no.3 s.62
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• pp.165-172
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• 2007

The purpose of this study was to analyze the sintering characteristics of gold and silver nanoparticles. In this study, gold and silver nanoparticles were prepared by using Inert Gas Cndensation (IGC). The sintering temperatures for gold and silver nanoparticles were $100{\sim}1000^{\circ}C\;and\'100{\sim}500^{\circ}C$, respectively. The sintering characteristics of gold and silver nanoparticles prepared by IGC were evaluated by X-ray diffraction(XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Gold and silver nanoparticles with the size of $1{\sim}100\;nm\;and\;10{\sim}100\;nm$, respectively, were obtained. The size of sintered gold and silver nanoparticles increased with an increase in the sintering temperature. XRD data showed that silver nanoparticles were similar with polycrystal single-phase.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.572-577
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• 2006

The physiochemical interactions of 1-methylcyclopropene (1-MCP) and adsorbing agents can be described using a very powerful tool, inverse gas chromatography (IGC). Sorption behavior of 1-MCP on various adsorbing agents was assessed using the profile peaks of 1-MCP at an infinite dilution concentration using the IGC technique. Chromatogram peaks of 1-MCP adsorption were not observed for the adsorbing agent activated carbon. The forms of sorption isotherms followed Henry's law, and behaved according to the binding site theory. Specific retention volume and distribution coefficients for 1-MCP on the adsorbing agents were determined at 50, 60, 70, and $80^{\circ}C$, respectively. Silica gel had a much higher number of binding sites for 1-MCP compared to Tenax-TA and activated clay agents. Meanwhile, activated carbon proved to be a very strong binding agent for 1-MCP based on 1-MCP efficiency experiments on the selected adsorbing agents. However, as a proper means of delivering 1-MCP molecules to fresh food products, activated carbon is not fit for the binding and release of 1-MCP gas under dry or high humidity conditions because activated carbon has a strong affinity for 1-MCP, even when treated with distilled water.

• Journal of Ocean Engineering and Technology
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• v.31 no.2
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• pp.91-102
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• 2017

Recently, a new type of LNG membrane Tank called the "KC-1 membrane LNG Tank" was developed by KOGAS (Korean Gas Corporation). It is necessary to estimate the temperature distribution of the hull structure and insulation system for this new LNG tank, as well as the BOR (Boil-Off Rate) when exposed to outside temperature conditions to ensure the integrity of the tank structure and limit LNG evaporation, from a safety evaluation point of view. In this study, temperature distribution calculations for the hull structure and insulation system of the KC1 membrane tank were compared by employing four numerical approaches under the IGC condition. Approaches 1-3 studied 2D simulations and approach 4 used a 3D numerical simulation. Approach 1 was calculated by in-house Excel VBA codes and the three other approaches utilized ANSYS Fluent. The BOR of approach 4, the 3D simulation case, for the IGC condition was 0.0986%/day.

• Journal of the Korean Geographical Society
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• v.30 no.2
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• pp.188-199
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• 1995

This International Geographical Symposium is to comemorate the 50th anniversary of the Korean Geographical Society. The Korean Geographical Society (KGS) which is the headquater of the geogaphical study will be play a main role to promote International Geographical Conference(IGC). And KGS hopes to prepare for the success of IGC and to examine the ability of the Korean Geographical Society for holding IGC in Seoul, in 2000. Above all, we expect to confirm what vision of the spatial structure our geographers have had for the last 50 years and in the position of the Korean Geographical Society, we present various studies on the spatial structure of the Unified Korea and through the discussion of the members we are going to lead our common interest to the key of reunification and motivate this studies more actively. We think that German geographers who have been studying the establishment of the spatial structure before and after the reunification of Germany will help in setting spatial structure of reunified Korea. In the second part of seminar, we will have a lecture on "Geography in the 21st Century; its Perspectives and Contribution". This lecture will prepose the trends of international geographical study and discipline, to Korean geographers and encourage them to realize what position we are in on the level of international geography and intensify their study. In the end of twentieth centuries, Korean geographers, who accessto postmodernism, hope to develope the unique subject matter and discipline regrardless of the 50 year-partition of the Korean Peninsula through the study of geobraphy. What can we suagest to geographers under the unique spatia1 structure of the divided peninsula\ulcorner How will our country develope in the future when DMZ, the last remains of cold war, vanishes and our reunified country becomes\ulcorner These subject matters will be issued in this International Geographic Conference. These issued subject matters and procedures of discussion will stimulate younger students to have interest in our unique geographic environment and to set up thier own method of study. In the third part of seminar, a special lecture on "Half-century of Korean Geography: It's Reflection and Perspective", the product and the subject of each part in geography will be discussed. Because this seminar is for the first time in 20 years after the 30th anniversary, the evaluation and the comment of each field in geography will be focused on because the achievement of each member's study is evaluted and refered to objectively. The newly developed field ewll be proposed, as well as the evaluation and the result of the Korean Geographical Society. The criticism and the proposal of the Korean Geographical Society will encourage the study of each member. And it will contribute to the development of the Korean Geographical Society. We hope all the issued papers to be published as atreatise and circulated to all members, university liberaries, each institution etc. There is no doubt our research and study will affect geographers and geography teachers to use this treatise. If possible, we will make public editions to distribute widely for students who study geography. It will help students to study geography encouragingly and to understand a correct structure and to commit themselves to promote the developed industrial country when they are playing a leading part in society. And we will contribute this issue to all the institutes such as the congress, each department of government, the political parties, the economic circles and private institutes, in order to make them understand our academic efforts and activities. Besides, we hope this contribution will give them much understanding and interest about 2000 IGC in Seoul beforehand.in Seoul beforehand.