• Proceedings of KOSOMES biannual meeting
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• 2008.05a
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• pp.121-124
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• 2008

Tarballs formed by HEBEI SPIRIT oil spill observed in the south-western sea of Korea from December 27 2007. The tarballs were removed by the response party, which Korea Coast Guard became a center of organization. The amounts of removing tarballs form the sea and the coast were 0.345 tons and 1,739 tons, respectively. The number of persons, in order to remove the tar balls from the south-western sea of Korea, counted about 97,000 persons, including 25,000 volunteers. In this paper, we introduced the response methods of tarballs entering into the south-western sea of Korea such as a landing net, meshes and so on.

• Journal of the Korean Society for Marine Environment & Energy
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• v.12 no.4
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• pp.279-283
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• 2009

Approximately 12,547 kL of oil from the tanker 'Hebei Spirit' released into the western sea of Korea, which subsequently reached and covered extensive areas of the western coastlines of Korea. In the following days great numbers of tar balls hit the southwestern coast. Three different cleanup methods were used to mediate the southwestern coastline tar ball pollution by Korea Coast Guard (KCG) net setting, manual pick up, and sweeping them up. Net setting was useful in protecting coastlines from being hit by tar balls. The cold weather in winter conditions helped the tar ball response efforts because it caused them to harden, allowing them to be swept up from beaches and to be gathered up by hand.

• Proceedings of the Korean Society of Tobacco Science Conference
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• 1997.10a
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• pp.91-113
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• 1997

One mg tar cigarettes represent a growing segment of the market, in various parts of the world but specially in the Far East. Cigarette design of ultra low tar cigarettes is not easy to manage: a simple extension of the techniques used in the design of the low tar segment will usually lead to tasteless cigarettes. A detailed analysis of the design of commercial ultra low tar cigarettes in different countries shows that no 《dominant design》 has yet been adopted. Blend composition, blend density, filter design, degree of filter ventilation all vary in a large range from cigarette brand to cigarette brand, and will influence the puff number, the tar concentration in each puff and ultimately the taste. We will report and comment on the detailed analysis of 17 commercial brands of ultra low tar cigarettes. We will then review the specific influence of tobacco chemical composition, introduction of reconstituted tobacco, influence of cigarette paper characteristics, selection of filter ventilation components on the burn characteristics and tar delivery; to conclude that the commercial success of an ultra low tar cigarette is linked to a very delicate balance between this techniques and... good marking of course!

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.6
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• pp.639-646
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• 2009

High-flow steel-fiber reinforced mortar may induce a certain fiber orientation distribution in the process of placing and thus have an influence on the tensile properties. In this paper, the variation of the fiber orientation distribution according to the flow of high-flow steel-fiber reinforced mortar was estimated in numerical simulation. The analytical results present that the major variation of fiber orientation distribution is made within 150mm of flow distance, thereafter the tendency of the fiber orientation distribution is not noticeable even though the peak of distribution density in the orientation parallel to the flow direction get bigger along the distance. Considering the close relation between the fiber orientation and the tensile behavior of composite, prediction of fiber orientation distribution make it possible to predict the variation in the tensile behavior of high-flow steel-fiber reinforced mortar according to the flow.

• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.42-49
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• 2012

This study was carried out to investigate the toxicity of food Red No.2 in the Sprague-Dawley (SD) female rat for 4 weeks. SD rats were orally administered for 28 days, with dosage of 500, 1,000, 2,000 mg/kg/day. Animals treated with food Red No.2 did not cause any death and show any clinical signs. They did not show any significant changes of body weight, feed uptake and water consumption. There were not significantly different from the control group in urinalysis, hematological, serum biochemical value and histopathological examination. In conclusion, 4 weeks of the repetitive oral medication of food Red No.2 has resulted no alteration of toxicity according to the test materials in the group of female rats with injection of 2,000 mg/kg. Therefore, food Red No.2 was not indicated to have any toxic effect in the SD rats, when it was orally administered below the dosage 2,000 mg/kg/day for 4 weeks.

• Journal of the Korea Concrete Institute
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• v.24 no.6
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• pp.745-752
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• 2012

This paper studies the effect of the compressive strength for combined alkali-activated slag mortars. The effect of activators such as alkali type and dosage factor on the strength was investigated. The alkalis combinations made using five caustic alkalis (sodium hydroxide (NaOH, A series), calcium hydroxide ($Ca(OH)_2$, B series), magnesium hydroxide ($Mg(OH)_2$, C series), aluminum hydroxide ($Al(OH)_3$, D series), and potassium hydroxide (KOH, E series)) with sodium carbonate ($Na_2CO_3$) were evaluated. The mixtures were combined in different dosage at 1M, 2M, and 3M. The study results showed that the compressive strength of combined alkali-activated slag mortars tended to increase with increasing sodium carbonate. The strength of combined alkali-activated slag mortars was better than that of control cases (without sodium carbonate). The result from scanning electron microscopy (SEM) analysis confirmed that there were reaction products of calcium silicate hydrate (C-S-H) and alumina-silicate gels from combined alkali-activated slag specimens.

• Korean Journal of Logic
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• v.17 no.1
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• pp.33-70
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• 2014

We still do not know against what histocial/philosophical background and motivation was Tarski's definition of logical consequence introduced, even if it has had such a strong influence. In view of the centrality of the notion of logical consequence in logic and philosophy of logic, it is rather shocking. There must be various intertwined reasons to blame for this uncomfortable situation. There has been remarkable progress achieved recently on the history of analytic philosophy and modern logic. In view of the recent developments of the controversies involved, however, we will have to wait years to resolve all this uneasiness. In this gloomy situation, Douglas Patterson's recent study of Tarski's philosophy of language and logic seems to have the potential to turn out to be a ground breaking achievement. [Patterson (2012)] This article aims at reporting the state-of-the-art in this problem area, and fathoming the future directions of research by examining critically some unclear components of Patterson's study.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.629-632
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• 2008

In the concrete repairing industry, it's very significant to apply adequate repair materials and construction method in order to extend service life of deteriorated concrete structure efficiently. also, adequate diagnosis of deteriorated structure's status should be involved. This paper describes an investigation of bond strength of polymer modified mortar applied both old deteriorated concrete surface substrate and well cured new concretes. The purpose of this investigation is comparing how much the tensile bond strength on construction site is different from laboratory test results. in the results of investigation, most of sample tested in laboratory is in compliance with KS F 4042's specification. and most of results of construction site are not in compliance with the specification cause of low tensile strength of concrete's surface.

• Proceedings of the Korean Society of Tobacco Science Conference
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• 1997.10a
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• pp.79-90
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• 1997

The world-wide cigarette market is becoming increasingly regulated. This involves restrictions on the freedom to advertise, restrictions on where people can smoke, and in some ways of most importance, limits on cigarette smoke deliveries. In particular, in an increasingly large number of countries maximum tar legislation is being enacted. In many cases, such as the European Union, this type of legislation is progressive and over time it is entirely conceivable that maximum permitted tar deliveries will be reduced to as low as 5 mg, possibly with additional restrictions on smoke nicotine deliveries. In addition, the pace of change is increasing as more and more countries embark on tar reduction programmes. The key challenge facing the cigarette industry is to manage these changes in such a way which ensures that product acceptability is maintained at as high a level as is possible in these circumstances. There are a number of ways of achieving this involving filter ventilation, modifying blends and using different filter constructions The real innovation comes when combining these in a way that gives the most acceptable balance of all these competing variables as far as the smoker is concerned. Undoubtedly, the nature of the filter is of crucial importance in designing the most acceptable low tar products, and this paper will discuss some of the filter types which are currently in use in the various low tar markets around the world. Also, some thoughts about the future in terms of new filter developments will be presented.

• Fire Science and Engineering
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• v.24 no.4
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• pp.12-17
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• 2010

The purpose of this study is to determine how effectively waste tire recycled material mixed with flame retardant work in combating fire. As discovered in the previous study, waste tire mixed with cement mortar has more insulation capacity. However, this mortar is weak against fire. Therefore flame retardant, with a specific proportional mix, will be added to increase its fire prevention capacity. Tests will be made in accordance with ISO 5657 procedures for measuring fire ignition time, flame and shape variation of test pieces at the Building Material Test Institute. The test piece will be set up with horizontal levels having a constant radiation heat of $1{\sim}5W/cm^2$. Temperature transfers and increases from the surface into the interior. Combustible gases result due to pyrolysis, and regular contact is maintained between the fire source and the center of the test piece for assessment purposes. Ignition has not been occurred without adding retardant meaning that there is almost no possibility of ignition of waste tire particle. This fact can be considered as fire load to appreciate a volume of combustion materials. Flame is not occurred due to heat-absorbing effect by adding non-organic series retardant into waste tire particle. Conclusions have been summarized as follows; 1) Combustion of building material can be decreased by adding retardant to waste tire-mixing mortar. But compressive strength and insulation capacity of the material should be measured later. 2) Firing prevention and ignition are main points of building fire. Reasonable fire engineering assessment of interior material should be made for establishing effective disaster prevention system.