• 동력기계공학회지
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• 제17권1호
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• pp.27-35
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• 2013

SCR (Selective Catalytic Reduction) on DPF (Diesel Particulate Filter) is a multi-functional after-treatment device which integrates soot filtration and DeNOx function into a single can. Because of its advantage in package and cost, the SCR on DPF is considered as a potential candidate for future application. It inherently employes wall flow type monolithic reactor so ash included in exhaust gas may deposit inside the inlet channel of this device. This study is intended to identify the impact of ash deposit on SCR reaction under wall flow type monolithic reactor. Simulation approach is used so relevant species transport equations for wall flow type monolith is derived. These equations can be solved together with momentum conservation equations and give solution for conversion performance. Both ash deposit and clean catalyst case are simulated and comparison of these two cases gives an insight for the impact of ash deposit on conversion performance. Ash deposit can be classified as ash layer and ash plug. and impact of ash deposit is described along with different morphology of ash deposit.

• Journal of Pharmaceutical Investigation
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• 제32권1호
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• pp.41-45
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• 2002

The purpose of this study is to microencapsulate a highly hygroscopic drug, pyridostigmine bromide (PB), with a waterproof wall material, in order to increase the flowability of the drug particles. Polyvinylacetaldiethylaminoacetate (AEA), Eugragit E and Eugragit RS were examined as the wall materials. Microcapsules containing PB were prepared by the evaporation technique in an acetone/liquid paraffin system using aluminum tristearate as a core material, and evaluated for drug encapsulation efficiency, surface morphology, particle size and drug dissolution. The encapsulation of PB in the wall material was almost complete. Among the wall materials examined, AEA exhibited the most excellency in shape, surface texture, flowability, size distribution of microcapsules. Above results suggest that AEA would be a potential wall material for microcapsulation of highly hygroscopic drugs, such as PB. Through microencapsulation with AEA, inconvenience of handling of PB powders encountered in the process of weighing and packing the powders to tableting die or capsule body could be greatly improved.

• 한국염색가공학회지
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• 제20권4호
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• pp.31-42
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• 2008

Tricrecyl phosphate(TCP)-containing polyurea microcapsules were prepared by interfacial polymerization using aromatic 2,4-toluene diisocyanate(TDI) and ethylenediamine(EDA) as wall forming materials. The effects of the protective colloids of polyvinylalcohol(PVA) and gelatin were investigated through experimentation. The mean size of prepared polyurea microcapsules was smaller and the surface morphology of the microcapsule prepared by the PVA as protective colloid was much smoother than the gelatin. As the concentration of protective colloid increased, the wall membrane of the polyurea microcapsules became more stable, the thermal stability of the wall membrane increased, the mean particle size became smaller, and the particle distribution was more uniform. PET containg microTCPs have a higher activation energy of decomposition, higher char content and lower heat of combustion.

• 한국염색가공학회지
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• 제19권5호
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• pp.30-36
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• 2007

Cypermethrin-containing polyurea microcapsules were prepared by interfacial polymerization using aromatic 2,4-toluene diisocyanate(TDI) and Ethylene diamine(EDA) as wall forming materials. The effects of the protective colloids of polyvinylalcohol(PVA) and gelatin were investigated through experimentation. The mean size of the polyurea microcapsules was smaller and the surface morphology of the PVA was much smoother than gelatin. In addition the release behavior was much more controlled and better sustained. As the concentration of protective colloid increased, the wall membrane of the polyurea microcapsules became more stable, the thermal stability of the wall membrane increased, the mean particle size became smaller, and the particle distribution was more uniform. The release behavior of the core material changed according to the concentration. As the gelatin concentration was increased, a more controlled and sustained release behavior was observed. However, in the case of PVA, the increase of PVA concentration lead to a more rapid release rate.

• 한국재료학회지
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• 제18권5호
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• pp.277-282
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• 2008

The effects of the field emission property in relation to the surface morphology and adhesion force were investigated. The single-wall-nanotube-based cathode was obtained by use of an in-situ arc discharge synthesis method, a screen-printing method and a spray method. The morphologies of the formed emitter layers were very different. The emission stability and uniformity were dramatically improved by employing an in-situ arc discharge synthesis method. In this study, it was confirmed that the current stability and uniformity of the field emission of the cathode depend on the surface morphology and adhesion force of the emitters. The current stability of the field emission device was also studied through an electrical aging process by varying the current and electric field.

• 한국실내디자인학회논문집
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• 제19권4호
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• pp.90-98
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• 2010

This study intends to understand the change of the library's bookshelves shape, composition and arrangement based on the social-culture in each period. For this purpose, this study analyzes the morphological shift of the library's bookshelves and knowledge information focused on the history of western libraries from the ancient libraries to the modern public libraries before the 20th century. And the results are follows. 1) We can make sure that the changes of the library's bookshelves are based on the environmental factors like social cultural political factors and also understand that the knowledge information are developed based on the function which is decided by the needs of the times and the serious necessities of users. With this reason, the morphology and the function of the library's bookshelves have been changed. 2) The characters and meanings of the library's bookshelves are changed with the times from movable type to fixed type, from closing type to opening type, from privileged use to public use, from religious contents to general scientific contents. 3) The morphology of the library's bookshelves are shifted from cylindrical box to Chest type Press type and Lectern system, Stall system, Wall system and advanced to Mixed(Stall+Wall) system. 4) The construction and arrangement methods of the library's bookshelves are determined by the convenience and efficiency of the installation for the perusal environments as well as the regarding to the social-cultural factors. The arrangement criteria are determined by the security topics in the earlier stage, after that determined by the lightening topics and nowadays the access topics to the information. These analysis results are very useful to research the technology of the library's bookshelves to be changed continuously and also to forecast the morphology of the library's bookshelves can be planned in the spaces of the future libraries.

• 식물분류학회지
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• 제41권1호
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• pp.35-46
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• 2011

한국산 가지과 12속 22분류군의 종자 특징을 해부현미경과 주사전자현미경을 통하여 관찰하고 자세히 기재하였다. 연구된 분류군의 종자 색깔은 노란색에서 검정색까지 관찰되며, 종자 형태는 신장형에서 원형까지 나타났다. 종자 크기는 길이 0.56-4.29 mm, 폭 0.38-3.20 mm로, Datural metel이 가장 크고 Petunia hybrida가 가장 작았다. 종자의 표면무늬는 세 가지 유형으로 과립형, 과립상-망상형, 망상형이 나타났다. 수층벽의 유형은 파상형과 직선형으로 관찰되었다. 대부분의 분류군은 파상형을 갖고, Datura속, Petunia속, Scopolia속에서는 직선형만 관찰되었으며, Nicandra physalodes는 직선형과 파상형을 모두 갖는다. Solanum속내 일부 분류군에서는 종자의 수층벽 상단부위에 모용처럼 보이는 섬유소가 관찰되었다(S. japonense, S. lyratum, S. lycopersicum). 한국산 가지과에 대한 종자의 형태학적 형질을 속별로 기재하였고, 그 분류학적 유용성에 대해 논의하였다.

• 치과방사선
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• 제14권1호
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• pp.17-26
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• 1984

The purpose of this study was radiographic analysis of the morphology of maxillary sinus in adolescents and adults. In order to analize the morphology of maxillary sinus in view point of anteroposterior width of medial wall, vertical distance between antral floor and nasal floor level, anterior extension, distance between antral floor and maxillary 1st molar apex, and types of lower border of maxillary sinus, specialized maxillary projection and periapical view with paralleling technique was taken. The author examined orthopantomograms and intraoral standard views taken from 400 adolescents and adults ranged 15-65 year-old. The obtained results were as follows: 1. The antero-posterior width of medial wall of maxillary sinus was 32.80mm in 15-19 year-old group, 33.86㎜ in 20-24 year-old group, 34.09㎜ in 25-29 year-old group, and 33.67㎜ in 30-65 year-old group, and the left maxillary sinus was somewhat smaller than the right. 2. The vertical distance between antral floor and nasal floor level was 8.49㎜ in 15-19 year-old group, 9.05㎜ in 20-24 year-old group, 8.95㎜ in 25-29 year-old group, and 8.32㎜ in 30-65 year-old group. 3. The order of anterior extension of maxillary sinus were distal half of canine, mesial half of canine, mesial half of 1st premolar, and distal half of 1st premolar. 4. The distance between antral floor and maxillary 1st molar were 4.36㎜ in 15-19 year-old group, 4.77㎜ in 20-24 year-old group, 3.58㎜ in 25-29 year-old group, and 2.33㎜ in 30-65 year-old group. 5. The order of the types of lower border of maxillary sinus were entire downward type, close type, partially downward type, waving type, separating type, and indistinct. In the types of antral floor, there was a tendency to increase the seperating type with age.

• 식물분류학회지
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• 제36권1호
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• pp.1-19
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• 2006

한국산 고란초과의 포자 형태를 광학 및 주사현미경으로 관찰하여 기재하고 속검색표를 작성하였다. 포자는 방사상칭의 삼지형인 주걱일엽을 제외하고는 모두 좌우상칭인 단지형이다, perispore는 모든 종에 존재하며 미역고사리속, 일엽초속, 밤일엽속, 주걱일엽속, 창고사리속 및 콩짜개덩굴속은 perispore와 exospore가 서로 유사하지만, 고란초속의 경우는 두터운 perispore에자상 돌기와 두상 돌기가 혼재하여 평활상의 exospore와 차이를 보인다. 석위속의 석위와 애기석위는 perispore와 exospore의 표면무늬가 서로 유사하지만 세뿔석위와 우단일엽은 perispore가 각각 난선상과 유두상 돌기를 가져서 exospore와는 크게 다르다. 그리고 exospore가 추문상의 무늬를 갖는 군은 미역고사리속과 주걱일엽속이며, 일엽초속은 불규칙한 유두상 돌기가 있는 난선상, 고란초속과 창고사리속은 평활상이지만 창고사리속의 경우, 드물게 유두상 돌기도 분포한다. 밤일엽은 미립상 혹은 소형의 유두상 돌기가 밀생하고 콩짜개덩굴은 복잡한 망상무늬를 갖는다. 한편 석위속은 분류군에 따라 유두상 돌기가 있거나 또는 평활상이다.

• Journal of the Korean Wood Science and Technology
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• 제43권2호
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• pp.145-155
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• 2015

Fiber morphology and basic characteristics of Legi bamboos (Gigantochloa atter) growing on Yogyakarta were studied considering their age and height positions in the culms. Culms of 4, 16, and 40 months were harvested, and their total lengths were measured. The length, diameter, and wall thickness of each internode were measured. All the sample culms were divided into three different parts along the height, and their fiber dimension and physical properties were observed. The data obtained were analyzed by analysis of variance. The results showed that the culms had a diameter of 5.8 to 10.8 cm. The lowest internodes always showed the shortest length and the thickest wall. The culms had an average fiber length of 2.41 mm and Runkel ratio of 0.61. Fiber length was affected by the height, while fiber diameter, lumen diameter, and fiber wall thickness were affected significantly by the age of the culms. The culms had high green moisture content (GMC) of 157.89%, and basic density (BD) of $456.67kg.m^{-3}$, a total longitudinal shrinkage of 0.35%, and relatively low R/T shrinkage ratio. The interactions between age and height were affected GMC and BD.