• International Journal of Highway Engineering
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• v.19 no.2
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• pp.97-102
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• 2017

PURPOSES : Emulsified asphalt is critical for road construction. The objective of applying asphalt emulsion as an adhesive is to prevent the phenomenon of debonding between the upper and lower layers. The quantity and veriety of bituminous material can be varied according to the type of pavement and site conditions. The objective of this study is to reveal the optimum application rates of the emulsified asphalt materials by types of tack-coats using Interface Shear Strength(ISS). METHODS : In the research, emulsified asphalt was paved on the surface of the divided mixture. The specimens of paving asphalt emulsion were utilized to evaluate the bond strength of tack-coat materials. In the evaluation process, NCHRP Report 712 was utilized to investigate the Interface Shear Strength, which reflects the bond capacity of asphalt emulsion. Then, the optimum residual application rates by tack-coat types were determined using regression analysis. RESULTS :As a consequence of squared R values investigated from 0.7 to 1 as part of the regression analysis, the tendency of predicted ISS values was compared with the results. The optimum residual application rates of AP-3, RS(C)-4, QRS-4, and BD-Coat were determined to be $0.78{\ell}/m^2$, $0.51{\ell}/m^2$, $0.53{\ell}/m^2$, and $0.73{\ell}/m^2$, respectively, utilizing 4th regression analysis. CONCLUSIONS :Based on the result of this study, it was not feasible to conclude whether higher residual application of tack-coat material leads to improved bond capacity. Rather, the shearing strength varies depending on the type of pavement.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.1
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• pp.27-32
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• 2009

The main objective of this study is to develop a test for measuring the bond shear strength between pavement layers. The research is also conducted to evaluate tack coat materials and application rate in porous pavement. The experiment includes using two types of emulsions (RSC-4, Modified Emulsion) and a asphalt binder type (HM-1). HM-1 was developed to be applied in porous pavement. The bond shear strengths were measured by a direct shear type device under various test conditions. The shear strength may not be appropriate in the evaluation of the bond shear strength, while the toughness of the test may be useful. In case of the tack coat application rate in porous pavement, RSC-4 has to be used a minimum amount of $0.8l/m^2$ and modified emulsion asphalt has to be applied a volume of use $0.5{\sim}0.6l/m^2$. HM-1, asphalt cement type, is far stronger bond shear strength than emulsified asphalt tack coat and had showed the excellent trackless property.

• Korean journal of food and cookery science
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• v.11 no.3
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• pp.237-243
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• 1995

"Woomegi Dduck" is one of Korean traditional pan fried rice cake made from glutinous rice by Tack-joo(rice wine) or boiling water. The optimum conditions for the preparation of "Woomegi Dduck" were investigated. The Hardnes, Cohesiveness, Gumminess, Chewiness, Adhesiveness of "Woomegi Dduck" added Tack-joo or boiling water measured by Rheometer, didn′t have significant difference between samples. The result of color test was L-Value, a-Value, b-Value and E Value of Woomegi Dduck added boiling water and 20％ rice flour were high. The best recipe of Woomegi Dduck was glutinous rice flour 50g, rice flour 20g, Tack-joo 30$m\ell$, or boiling water 25$m\ell$, sugar 10g.

• The Korean Journal of Pain
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• v.11 no.2
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• pp.343-345
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• 1998

Stellate ganglion block and cervical epidural nerve block are frequently practiced in pain clinics because of simple procedure and good effect. Nerve block at head and neck may produce serious complication such as loss of consciousness and cardiac arrest. Blood supply is rich in neck and inadvertent arterial injection of local anesthetics may enter directly into brain. We experienced convulsion and respiratory arrest during SGB and cervical epidural block. The patients were resuscitated successfully and recovered without any adverse effects.

• Journal of the Korean Graphic Arts Communication Society
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• v.10 no.1
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• pp.23-33
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• 1992

The negative pressure distribution curves of the exit of printing nip were obtained by the transducer type tackometer. As the results, found that the elasticity of rubber rollers and pastic viscosity affect to the maximum negative and positive pressure but, the gap of the printing nip didn`t affects to the tack values of ink and ink film thickness. Ink spritting is accured by negative pressure and inks viscoelasticity. And the tack value is affect by properties of the vehicle component in the inks.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.74-74
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• 2012

섬유 프리프레그(Prepreg)는 강화섬유를 수지에 함침하여 B-stage로 만든 복합재료의 중간성형재료이다. 최종적으로 프리프레그를 금형에 적층하여 가열 가압하여 수지를 경화함으로써 최종제품이 완성된다. 본 연구에서는 직물형 프리프레그를 사용하였는데, 사용되는 직물형태로는 복합재료 성형공정에서 형태안정성이 우수한 평직물과 능직물이 주로 사용된다. 직물형 프리프레그를 사용한 복합재료는 작업성과 형태안정성이 우수하면서 내충격특성이 우수하여 오토바이용 헬멧, 방탄용 헬멧 등에 주로 사용된다. 프리프레그에 요구되는 주요 특성중 하나는 Tack성으로서, 성형 과정에서 프리프레그를 여러 장 적층할 때 적층된 층 간에 미끄러지지 않으면서 잘 고정되어 적층 작업을 원활하게 하는 역할을 한다. Tack성은 수지의 B-stage 경화 후의 점성 거동에 따라 변화될 수 있는 것으로 표면의 끈끈함의 정도로서 알 수 있다. Tack성은 온도에 민감하여 측정 시에 일정한 온도의 유지가 중요하다. 이러한 온도에 대한 민감성 때문에 프리프레그의 저장시 저온에서 저장하는 것이 원칙인데, 상온에 있을 경우 시간경과에 따른 Tack성 변화가 크게 나타나게 된다. 따라서 본 연구에서는 아라미드 섬유와 열경화성수지를 이용하여 프리프레그를 제조하고 이를 상온상태에서 보관 시 일정시간 경과에 따른 Tack성 변화를 알아보고자 하였다.

• Journal of Adhesion and Interface
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• v.6 no.3
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• pp.19-25
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• 2005

Synthetic rubber based pressure-sensitive adhesives (PSAs) usually containing SIS or SBS block copolymer, tackifier, plasticizer, and other additives are now widely used on various applications. As these PSAs are physically crosslinked and can be applied without the use of solvent, they are thermally processable and environmentally friendly. However these PSAs cannot be used in high temperature applications and in applications where solvent and chemical resistance properties are required. We developed the PSA adding UV curable system, such as thiol-ene system, to increase adhesion properties at elevated temperature. The adhesion properties such as probe tack, peel strength, shear adhesion failure temperature (SAFT) were evaluated. The probe tack test was conducted with varying probe materials and coating thickness of PSAs. Using the contact angle, the surface property of the cured PSAs was also observed.

• Korean Journal of Microbiology
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• v.5 no.2
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• pp.43-54
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• 1967

The characteristics of enzymic sources and its effective uses concerned with brewing of Yack-Tack Joo which is traditional and popular liquors for all Korean have been studied. Results obtained are as follows; 1)Kock Ja (enrich of fungi and yeast produced in Korean brewery) is found to be weak in its liquifying(600U.) and saccharifying activity(1300U.), so that it is useful to conbine two factors effectively for better brewing. 2) The additional ratio of Kok Ja per materials is seems proper at line of 20 percent for better fermentation and the enzymic preparations inoculated of microorganisms in wheat bran is seems proper at 25 percent line. 3) Adding the enzymic preperation in which the strain Rhyzopus had been inoculated to the experimental mash at 5 percent per material, the rate of fermentation was revealed highest degree than those of else. 4) It is not proper to add a single Bun Kok in fermentation, as it produce much acid in mash during brewing. 5) However, the enzymic preparation composed of Asp usami and Rhyzopus sp. produced less acid in brewing. 6) The increasing of temparature in enzymic samples, temparatures of the mixtured Kuk(Kok Ja and enzymic preparation) are higher than those of single addition at the first stage in pre-fermentation, but there are no differences at the late stage of post-fermentation. 7) Amount of amino acids in the plot of enzymic prepation are found much more than those of single use at late stage of post-fermentation. In the plot of single use of Kock Ja, the amount was the most than else, the proteinase activity is strongest more than else. 8) In the brewing of Korean Tack-Yack-Joo, it is desirable less amount of acidity, more amount of amino acid, stronger liquifaction of starch and vigorous saccharification. Thren it was found that the application of two prepations(Kock Ja and Bun kok) is most effective to get moderate quality in Tack-Yack-Joo brewing.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.10 no.1
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• pp.7-14
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• 2014

There has been extensive experience associated with the operation of SGs wherein it was believed, based on NDE, that throughwall tube indications were present within the tubesheet. The installation of the SG tubes usually involves the development of a short interference fit, referred to as the tack expansion, at the bottom of the tubesheet. The tack expansion was usually effected by a hard rolling process and thereafter, in most instance, by the expansion of a urethane plug inserted into the tube end and compressed in the axial direction. The rolling process by its very nature is considered to be intensive with regard to metalworking at the inside surface of the tube and would be expected to lead to higher residual surface stresses. Alternate repair criteria(ARC) in the tack expansion area have been developed and applied to nuclear power plants in USA, however domestic nuclear power plants have not applied ARC for tubes in tubeheet area yet. In consideration of the degradation characteristics of tubes in the Steam Generator tubesheet, this paper suggests ARC application for tubes in the steam generator tubesheet of the domestic nuclear power plants in order to assure life time of the steam generator as well as nuclear power plants.

• Applied Chemistry for Engineering
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• v.18 no.2
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• pp.121-125
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• 2007

Siloxane monomer and oligomer were introduced to n-butyl acrylate and methyl methacrylate copolymer for improvement of water resistance and tactile sensation of acryl-type emulsion. Terpolymerimerization of n-butylacrylate, methyl methacrylate and siloxane monomer or oligomer was carried out in aqueous solution. The glass transition temperature (Tg) of terpolymer decreased with increasing siloxane monomer, however, the Tg of terpolymer increased with increasing siloxane oligomer due to the crosslinking of acrylated end group. The adhesion property and surface energy of the obtained terpolymer decreased with introducing siloxane monomer or oligomer in terpolymer. Decrement of tack and surface energy means the enhancement of water resistance and tactile sensation of the emulsion.