• Title/Summary/Keyword: disintegration

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A Study on the Minimization of Water Damage for the Asphalt Inlay of Old Concrete Pavement (노후 콘크리트 포장 절삭 덧씌우기의 침투수에 의한 파손 최소화 방안 연구)

  • Kang, Won Pyoung;Yeom, Kwang Jae;Suh, Young Chan;Lee, Kyoung Ha;Kang, Min Soo
    • International Journal of Highway Engineering
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    • v.15 no.4
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    • pp.53-63
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    • 2013
  • PURPOSES: The purpose of this study was to investigate the disintegration mechanism of concrete due to the infiltration of the moisture to the milling overlay pavement and to come up with a method to minimize the disintegration as well as verifying the effectiveness of the edge sealing and Fogseal method. METHODS : This study investigated the distress mechanism due to the infiltrated moisture remaining in the milling overlay pavement through chloride freezing test and verified the effectiveness of the sealing of the milling edge and fog seal methods, which have been devised to minimize the moisture infiltration, through laboratory water permeability test. Additionally, long-term pavement performance was compared for the effectiveness of the proposed method through under loading test, and field water permeability test was carried out to verify the field applicability of the proposed method. RESULTS: The result of the research confirmed that chloride deteriorates the concrete surface through disintegration and lowers its strength and that the laboratory moisture infiltration test verified the effectiveness of the milling edge sealing and fog seal methods in the deterrence of moisture infiltration to the overlay pavement with excellent long-term performance of the pavement treated with the proposed method. Although the field water permeability test revealed some deterrence of moisture infiltration of the milling edge sealing and fog seal methods to a certain extent, the difference was a little. CONCLUSIONS: The milling edge sealing and fog seal methods are limited in their effectiveness for the cases of improvident compaction management or mixture with large void, and it is believed that installation of subsurface drainage is more effective in these cases.

Disintegration Mechanism of a Coaxial Porous Injector (동축형 다공성재 분사기의 분열 메커니즘)

  • Lee, Keonwoong;Kim, Dohun;Son, Min;Koo, Jaye
    • Journal of the Korean Society of Propulsion Engineers
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    • v.20 no.2
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    • pp.39-45
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    • 2016
  • In a coaxial porous injector, a gas propellant is injected through the porous cylinder surface to the liquid jet which is encircled by a porous cylinder. In this study, to observe the differences in disintegration mechanisms between a shear coaxial injector and a coaxial porous injector, cold-flow tests and 2-D axisymmetric numerical analysis have been carried out. The shadowgraph images and Sauter mean diameters were compared in similar experimental conditions, and the effects of velocity distributions at the inner injector region on the disintegration of liquid jet were investigated through the numerical calculations. As a result, in high air mass flow rate condition, the disintegration performance of coaxial porous injector is better than shear coaxial injector, in spite of a lower velocity at the inner injector region.

Processes of Thufur Disintegration Mt. Halla (한라산 유상 구조토의 붕괴 프로세스와 요인)

  • Kim, Tae-Ho
    • Journal of the Korean association of regional geographers
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    • v.12 no.4
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    • pp.437-448
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    • 2006
  • Bare-topped thufur is called as frost scars, implying the rupturing stage of vegetated mounds, Field observations and measurements provide empirical information on the process and factors of thufur disintegration in Mt. Halla, Initial bare patches on mound apexes are scaled up by continuous removal of soil and vegetation, resulting in the formation of crater-like thufur, Frost action plays a primary role in thufur disintegration, In particular, pipkrake loosens soil particles within the bare patches and subsequently accelerates the degradation of vegetated mounds during periods with frequent diurnal freeze-thaw cycle and high soil moisture, Deflation also has an impact on thufur breakup in that the bare patches usually lack upper dark brown soil and are covered with granules, Withered shrubs such as Juniperus chinensis var. sargentii are frequently observed in frost scars and disrupted mounds, indicating that thufur disintegration has been probably influenced by global warming.

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The Family in Children's Literature and Its Disintegration (아동문학에 나타난 가족, 그리고 해체)

  • Won, Yoo-Kyeong
    • Journal of English Language & Literature
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    • v.58 no.1
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    • pp.117-142
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    • 2012
  • The education of children is one of the most important parts in children's literature. Children's literature, whose implied readers are both children and parents, is a good means to teach how they should behave and interact. Therefore, literary conventions of children's literature tend to be conservative with happy endings or fairy tale elements. Most of the children's literature of the 18th century were read as a conduct book which teaches children good manners and proper behavior, and at the same time served as a guidebook which tells parents how to discipline children. It emphasized the need of discipline to ascertain the hierarchy and order of the family, and cherished the close relationship between parents and children. In the 19th century, the ideal of family becomes more internalized. In the early 20th century, the ideology of family still remained, even though the world wars and economic depressions caused the cracks and collapses of the family. In the later 20th century, the disintegration of the traditional family was accelerated. The ideal of family based on the close relationship between parents and children, has had problems from the start. The attachment and over-closeness became stressful and sometimes could be poisonous. Recent children's literature shows the process of disintegration of the traditional nuclear family, children suffering in the fractured family, children's mental trauma, and nostalgia for the lost family. However, modern children's literature manages to find the lost or ideal surrogate family, and often shows fairy-tale elements such as mystical and heroic child protagonists or helpers who might solve all the difficult problems at once, despite the collapse of the family in reality.

Analysis of Disintegration Characteristics of OCC (골판지 고지의 해섬 특성 해석)

  • Lee Hak Lae;Youn Hye Jung;Lee Sang Gil;Kang Tae Young;Heo Young Dae
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.36 no.4 s.107
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    • pp.1-8
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    • 2004
  • Linerboards and corrugating mediums are being produced using recycled old corrugated containers (OCC) as major raw materials. The utilization rate of recycled fibers is ex­pected to increase further in the future to reduce raw material cost. Use of recycled fibers as raw materials for linerboard, however, causes many problems for papermakers. As the utilization rate of recycled fiber and number of recycling of fibers increases, quality and process problems including strength reduction and deterioration of machine runn­ability will increase. To overcome the problem of strength reduction associated with the use of recycled fibrous materials for producing quality linerboards, diverse extensive research efforts and new technological approaches have been taken. In this study, disintegration characteristics of aee was evaluated by determining the unslushed contents. The amount of unslushed content of KOCC was lower than AOCC. But contaminants content of KOCC was higher than AOCC. As the consistency in disintegration increased, the amount of unslushed fiber content decreased.

Biochemical Properties of Second Site Mutation of Human Immunodeficiency Virus Integrase

  • Kim, Do-Jin;Oh, You-Take;Lee, Sang-Kwang;Shin, Cha-Gyun
    • BMB Reports
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    • v.32 no.6
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    • pp.599-604
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    • 1999
  • A highly conserved amino acid, glutamic acid (Glu), present at position 152 in the catalytic domain of the human immunodeficiency virus type 1 (HIV-1) integrase (IN) protein has been known to be critical for enzymatic function since substitution of Glu 152 with other residues results in a complete loss of enzymatic activities. In order to better understand the role of Glu 152 as a conserved residue in enzymatic action, intragenic second site mutations have been introduced around residue 152 of a mutant IN (E152A), and their biochemical properties were analyzed in terms of enzymatic activities. Disintegration activities were found to be significantly restored in several second site mutant INs, while integration activities were only recovered weakly. However, endonucleolytic activities were not discovered in all the mutant INs. These findings indicate that the second site mutations can partially restore that catalytic structure of the active site disturbed by the E152A mutation and lead to the regaining of integration and disintegration activities. In addition, it is also suggested that endonucleolytic activity requires a more accurate structure of the catalytic site than that for the integration and disintegration activities.

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An Experimental Study on the Uniform Droplet Production Regions of Light Oil Blended with Fish Oil (어유혼합경유의 균일액상 생성영역에 관한 실험적 연구)

  • Jang, Jae-Eun;Ahn, Soo-Kil
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.28 no.2
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    • pp.164-170
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    • 1992
  • In order to understand and explain the spary combustion, it was necessary to understand the disintegration mechanisms of liquid jet. To understand the disintegration mechanisms of liquid jet, the disintegration phenomena and uniform droplet production regions of testing liquid jet was investigated by means of longitudinally vibration capillary nozzle, which was injected the testing liquids. The testing liquids were light oil and light oil and light oil blended with 25wt% fish oil (File fish oil, Sardine fish oil, Alaska pollac oil) The results can be summarized as follows: 1. The uniform droplet phenomena have been changed according to the frequency of capillary tube, the jet velocity and physical properties of testing oils. 2. Within the region of uniform droplet, Reynold number was increased as Weber number increases. 3. The lower limit of wave length in which uniform droplet was produced 0.8d which was lower than Rayleigh wave length 4. The light oil blended with file fish oil which has lower viscosity and surface tension had the widest uniform droplet production region on the frequency and velocity among testing oils. But light oil blended with sardine fish oil were similar with light oil in the uniform production region.

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A Study on the Disintegration and Spreading Behavior of Fuel-spray Emanating from a Liquid-thruster Injector by Pseudo-3D Spatial Distribution Measurement (준3차원적 공간분포 계측에 의한 액체추력기 인젝터 연료분무의 분열 및 확산 거동에 관한 연구)

  • Kim, Jin-Seok;Kim, Jeong-Soo
    • Journal of the Korean Society of Propulsion Engineers
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    • v.12 no.5
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    • pp.9-17
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    • 2008
  • Pseudo-3D spatial distribution of spray droplets is investigated by using Dual-mode Phase Doppler Anemometry (DPDA) in order to examine the disintegration and spreading behavior of spray exiting from liquid-propellant thruster injector. Spray injected from nozzle orifice with length-to-diameter ratio ($L/d_o$) of 1.67 and under the injection pressure of 27.6 bar is aligned to the vertical. Vertical and horizontal mean velocities of droplets, Sauter Mean Diameter (SMD), and volumetric flux decrease as droplets travel from center/upstream toward outer region/downstream of spray. Although the distribution of spray characteristic parameters is symmetric against the geometric axis of nozzle orifice, their absolute values are asymmetric.

Effect of Softcapsule Fill Formulation on the Stability and the Disintegration Time of Ginkgo Biloba Extract (연질캅셀 제제 처방이 은행잎 엑스의 안정성 및 붕해 시간에 미치는 영향)

  • Kim, Young Soo;Kim, Su-Dong;Yoon, Sung-Hwa
    • Applied Chemistry for Engineering
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    • v.10 no.6
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    • pp.848-851
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    • 1999
  • In order to increase the stability of Ginkgo Biloba extract, we investigated the effect of three different fill formulations(SBO, PEG400, and PEG600 fill types) on the stability of Ginkgo Biloba extract in three different shell formulations (ssmb, smb and gmb shell types). The stabilities of each types were evaluated by testing their disintegration time sunder the condition of $40^{\circ}C$, 75% relative humidity(RH) for 8 weeks. The formulation of Ginkgo Biloba extract with ssmb and PEG600 formulation type showed the best stability among them.

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Bioabaibility of Oxytetracycline and Erythromycin stearate (Oxytetracycline과 Erythromycin Stearate의 생체유용성 검토)

  • Lim J.K.;Chung M.H.;Shin S.G.;Cha I.J.
    • The Korean Journal of Pharmacology
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    • v.13 no.1 s.21
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    • pp.1-6
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    • 1977
  • The physicochemical equivalencies of drugs are not usually correlate to the generic equivalencies of drugs and the generic equivalencies of drugs produced by different manufacturers or different formulations are being called in question frequently. The bioabailability of two formulations of oxytetracycline and erythromycin stearate were performed in healthy human volunteers. At the same time, the disintegration testes were performed with randomly sampled materials in question. For the biological evaluation of new oxytetracycline formulation; tablet(250mg), two-way cross over study in 10 healthy young volunteers was performed using oxytetracycline capsule (250mg) as reference, Erythromycin stearate (250mg) tablets and capsules produced by different manufacturers were compared in a two-way cross over study in 12 subjects with same manner of oxytetracyclines. oxytetracycline tablets showed somewhat slow disintegration rate, but appeared not statistical differences in serum concentrations from the reference, up to six hours after ingestion. Erythromycin stearate capsules disintegrated more rapidly than enteric coated tablets. Serum concentrations of capsules were more variable and markedly lower (P<.005 after 2hrs) than the enteric coated tablets. Rapid disintegration of capsules may result in destruction of active chemicals owing to the interaction with gastric acid and the above factor may contribute mainly to the low serum level after ingestion of capsules.

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