• Title/Summary/Keyword: retarded

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Dissolution Characteristics of ph-Dependent Antacid Granules Agglomerated in High Speed Agitation Type Speed Agitation Type Granulator

  • Choi, Woo-Sik;Lee, Jung-Sun
    • Archives of Pharmacal Research
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    • v.18 no.5
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    • pp.314-319
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    • 1995
  • Antacid granules were prepared by agglomeration and powder method in high speed agitation type granulator. The copmositions of the test antacids were sodium bicarbonate nad magnesium carbonate nad a coating material was powder of polyvinylacetal diethyl-aminocacetate (AEA) and an additive material was talc powder. The dissolution characteristics of base from the antacid granules were investigated to evaluate neutralization capacity of hydrochloric profile of base and neutralization behavior, the following results were obtained : The prepared granules showed a pH-dependent dissolution pattern of a base. The dissolution profile of a base was varied with addition of talc powder as well as coating amount of AEA. The relationship between the ratio of dissolution retarded time for 20% and 10% AEA. The relationship between the ratio of dissolution retarded time for 20% AEA coated granules $\theta_{20}/\theta_{10}$ and the diameter reduction of the granules was explained by the rate process of neutralization of hydrochloric acid.

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Effects of Triacontanol on Growth and Peroxisomal Enzyme Activities in Radish (Raphanus sativus L.) Seedlings (무 유식물의 생장과 Peroxisome 효소 활성에 미치는 트리아콘타놀의 효과)

  • 진창덕
    • Journal of Plant Biology
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    • v.27 no.4
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    • pp.241-251
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    • 1984
  • The present study investigated the effects of triacontanol (TRIA) on plant growth and peroxisomal enzyme activities in radish seedlings. The optimum concentration of TRIA with respect to radish seedling bioassay was decided to 1.0mg $1^{-1}$. In comparison to untreated controls (including Tween 20 treatment), 1.0mg $1^{-1}$ TRIA treatment caused an increase in seed germination rate and root growth, but no stimulation in hypocotyl growth. Chlorophyll accumulation in cotyledon during carly development stage increased rapidly, and degradation of chlorophyll in later stage due to the cotyledon senesence was noticeably retarded. Increase of soluble protein content in cotyledon at early period of development was observed. Isocitrate lyase and catalase activity was not significantly different in both the treated and the untreated plants. But, glycolate oxidase activity was inhibited by TRIA down to 20% against controls. Also, the increase of the activity of peroxidase, a leaf-senescence marker enzyme, was continuously retarded over control for 8 days of development. Based on above results, TRIA was found to be active in both the growth and the peroxisomal enzyme activities of radish seedlings.

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Variation of Exhaust Gas Temperature with the Change of Spark Timing and Exhaust Valve Timing During Cold Start Operation of an SI Engine (스파크 점화기관의 냉시동시 배기밸브 타이밍 및 점화시기 변화에 따른 배기가스의 온도변화)

  • Yang Chang-Seok;Park Young-Joon;Cho Yong-Seok;Kim Duk-Sang
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.29 no.3 s.234
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    • pp.384-389
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    • 2005
  • Experimental study of variation of exhaust gas temperature was carried out with the changes of spark timing and exhaust valve timing during the cold start operation of an SI engine. To investigate the effects of these variables on combustion stability, cylinder pressure and exhaust gas temperature were measured and analyzed. Experimental results showed that exhaust gas temperature increased when spark and exhaust valve timings were retarded from the baseline cases. However, combustion stability during cold start deteriorated under the retarded conditions. To increase exhaust gas temperature for fast warmup of catalysts while maintaining combustion stability, an optimal condition for spark and valve timing retard should be appied for the cold start period.

Research on the Requests for the Design of Welfare Facility for the Disabled in the Railroad Station (철도역사내 장애인 편의시설의 디자인 요구사항에 관한 연구)

  • Kim Byeoung-Rae;Lee Sung-Ho
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.1725-1730
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    • 2004
  • The railroad station building is a public facility that many people use. The disabled persons cannot move as freely as the ordinary persons do, so the facility shall be considered on this matter. We reviewed on the features of the retarded, visually handicapped and mentally retarded persons upon moving, and calculated the minimum space required in their move, access and use of the reachable space, and we also analyzed the design factors so that the prior guidance can be considered for the visually handicapped such as installation of guidance facility, change of finishing material and Braille points block handrail to avoid obstacles for the use of senses of touch, hearing and remained eyesight of the visually handicapped. In addition, we also analyzed the requests of general design totally to analyze and arrange the design factors with the thought that the facility for the handicapped shall be useful for the ordinary people as well as the handicapped.

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Performance Analysis of Variable Valve for Diesel Engine with Cam-in-Cam System (디젤엔진용 Cam-in-Cam시스템 적용 가변밸브 성능해석)

  • Jeong, S.C.;Park, J.M.;Kim, T.K.;Lee, J.W.
    • Journal of ILASS-Korea
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    • v.22 no.1
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    • pp.22-28
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    • 2017
  • In this study, the effects of intake valve closing timing by using Cam-in-Cam system on combustion and emission characteristics for diesel engine were investigated under GT-POWER simulation environment. As a result, it was found that volumetric efficiency and effective compression ratio were decreased as the intake valve closing(IVC) timing is retarded due to its backflow effect. Also, we found that in-cylinder pressure, heat release rate and NOx emission were decreased as IVC timing was retarded. These show that the LIVC(late intake valve closing) can be effective to control AFR and mixing rate in diffusion combustion of diesel engine.

Texture Study in HDDR-treated Nd-Fe-B-type Particles

  • Kim, Jung-Hwan;Kwon, H.W.
    • Journal of Magnetics
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    • v.10 no.4
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    • pp.152-156
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    • 2005
  • Effects of the disproportionating hydrogen pressure and alloy composition on the texture in the HDDR-treated Nd-Fe-B particles were examined using the $Nd_{12.6}Fe_{81.4}B_6$ and $Nd_{12.6}Fe_{68.7}B_6Co_{11.0}Ga_{1.0}Zr_{0.l}$ alloys. Disproportionation kinetics of the $Nd_2Fe_{14}B$ phase in the Nd-Fe-B alloy was retarded significantly by the addition of Co, Ga and Zr. The retarded disproportionation kinetics of the $Nd_2Fe_{14}B$ phase ensured a wider processing win­dow in terms of disproportionating hydrogen pressure for achieving a texture in the HDDR-treated Nd-Fe-B alloy particles.

Dissolution Characterstics of Indomethacin Microcapsules Prepared Using Gelatin-Gum Arabic Complex Coacervation (젤라틴-아리비아고무를 써서 製造한 인도메타신 마이크로캅셀의 용출 특성)

  • Ku, Young-Soon;Kim, Hwa-Yeon
    • YAKHAK HOEJI
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    • v.28 no.4
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    • pp.223-229
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    • 1984
  • Microcapsules of indomethacin were prepared by the complex coacervation technique using gelatin-gum arabic as the wall-forming material. The effects of varying drug-to-matrix ratios and formalization time, and hydroxy propyl cellulose (HPC) added on the release of drug from microcapsules were studied. As the amount of wall-forming material increased, the drug content in the microcapsules decreased and the release of drug from microcapsules was retarded. The drug content was lower in the HPC added microcapsules than that in the microcapsules was retarded. The drug content was lower in the HPC added microcapsules than that in the microcapsules without HPC and the microcapsules with 1:4 drug-to-matrix ratio showed the slowest release. The release rate of the drug from microcapsules with 1:2 drug-to-matrix was delayed according to the increase of formalization time and the microcapsules formalized for 24hr showed ratio the most retardation.

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A Study of the Characteristics for Simile Comprehension of Children with Mental Retardation (정신지체 아동의 직유 이해에 관한 연구)

  • Shin, Hu-Nam;Park, Hee-Jung;Kwon, Do-Ha
    • MALSORI
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    • no.60
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    • pp.85-96
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    • 2006
  • The aim of the present study was to investigate a simile comprehension of children with and without mental retardation. Thirteen children with mental retardation and ten normal children with matched receptive vocabulary ability participated in the study. They were between five and eight years old in the age of receptive vocabulary. Fourteen picture plates were used and each plate consisted of three pictures. The findings were as fellows. First, children with mental retardation made significantly more errors than normal children in the comprehension of simile. Second, mental retarded children and normal children did not have a significant correlation between receptive vocabulary development and comprehension of simile. Finally, on simile interpretation type, children with mental retardation were likely to think a tenor into a vehicle because they failed to recognize the syntactic structure of simile, 'A is like B'. Thus, It is important to teach mental retarded children the syntactic structures of simile and to provide them with a variety of experience as well as to let them know an exact meaning of words.

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A Study for the Available Adjustment Range of Gain at P, PI Control for the Retarded Processes (시간지연을 갖는 제어대상에 대한 P, PI 제어의 유효 게인 조정 범위에 관한 연구)

  • 강인철;최순만;최재성
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2001.05a
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    • pp.207-212
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    • 2001
  • In this paper, a method to be able to decide the possible maximum gain of P, PI control for the retarded processes under stable condition is proposed. At first, adjustable parameter set causing stability limit are obtained based on the frequency domain condition which makes the roots of transfer function locate on the $j\omega$ axis. And the cut-in frequency $\omega{_p}$ to bring the parameter set to P control from PI control is derived by an equation with 2 parameters L and $T_m$ given, then $\omega{_p}$ is used to compute the maximum gain with stable condition. For the calculation, the controlled process of first order system with time delay element is introduced and all parameters are presumed to be time invariant.

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