• Title/Summary/Keyword: Cellular solid

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셀룰러 토폴로지를 이용한 솔리드 모델 스트리밍 (Streaming of Solid Models Using Cellular Topology)

  • 이재열;김현
    • 산업공학
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    • 제16권spc호
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    • pp.87-92
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    • 2003
  • Progressive mesh representation and generation have become one of the most important issues in network-based computer graphics. However, current researches are mostly focused on triangular mesh models. On the other hand, solid models are widely used in industry and are applied to advanced applications such as product design and virtual assembly. Moreover, as the demand to share and transmit these solid models over the network is emerging, the generation and the transmission of progressive solid models depending on specific engineering needs and purpose are essential. In this paper, we present a Cellular Topology-based approach to generating and transmitting progressive solid models from a feature-based solid model for internet-based design and collaboration. The proposed approach introduces a new scheme for storing and transmitting solid models over the network. The Cellular Topology (CT) approach makes it possible to effectively generate progressive solid models and to efficiently transmit the models over the network with compact model size.

셀룰러 토폴로지를 이용한 프로그레시브 솔리드 모델 생성 및 전송 (Generation and Transmission of Progressive Solid Models U sing Cellular Topology)

  • 이재열;이주행;김현;김형선
    • 한국CDE학회논문집
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    • 제9권2호
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    • pp.122-132
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    • 2004
  • Progressive mesh representation and generation have become one of the most important issues in network-based computer graphics. However, current researches are mostly focused on triangular mesh models. On the other hand, solid models are widely used in industry and are applied to advanced applications such as product design and virtual assembly. Moreover, as the demand to share and transmit these solid models over the network is emerging, the generation and the transmission of progressive solid models depending on specific engineering needs and purpose are essential. In this paper, we present a Cellular Topology-based approach to generating and transmitting progressive solid models from a feature-based solid model for internet-based design and collaboration. The proposed approach introduces a new scheme for storing and transmitting solid models over the network. The Cellular Topology (CT) approach makes it possible to effectively generate progressive solid models and to efficiently transmit the models over the network with compact model size. Thus, an arbitrary solid model SM designed by a set of design features is stored as a much coarser solid model SM/sup 0/ together with a sequence of n detail records that indicate how to incrementally refine SM/sup 0/ exactly back into the original solid model SM = SM/sup 0/.

Solid State Sintering of Calcium Phosphate Ceramic Composites and Their Cellular Response

  • Cho, Yeong-Cheol;Kong, Young-Min;Riu, Doh-Hyung
    • 대한금속재료학회지
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    • 제50권9호
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    • pp.691-695
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    • 2012
  • Calcium phosphate ceramic composites, consisting of hydroxyapatite(HA) and tricalcium phosphate (TCP), were fabricated by solid state sintering in order to investigate the effect of their initial compositions on microstructural evolutions and biocompatibility. All the sintered calcium phosphate ceramics exhibited almost full densification, while the grain growth of the composites increased with an increasing TCP content in the green body. The TCP phase transformed into a Ca-deficient HA phase during sintering via the diffusion of calcium ions from the HA phase into the TCP phase. The phases formed in the composites significantly affected the biocompatibility of the composites. The HA-matrix ceramic composites with TCP had a better cellular response than the pure HA ceramics, presumably due to the newly formed Ca-deficient HA.

소아에서 발생한 췌장의 유두상 낭성 종양 2예 (Solid and Papillary Cystic Neoplasm of Pancreas in Children)

  • 최성일;오수명
    • Advances in pediatric surgery
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    • 제6권2호
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    • pp.134-138
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    • 2000
  • Solid and papillary cystic neoplasm of pancreas is an uncommon low grade malignant tumor. It is predominant in young female between the second and third decades of life, and amenable to cure by surgical treatment. The authors report two cases of solid and papillary neoplasm of pancreas pathologically verified at Kyung Hee University Hospital. The first case was an 11-years old female patient and the other case was a 12-years old male. Symptoms were abdominal discomfort, nausea and vomiting in both cases and abdominal pain in the female patient. CT finding included a solid and papillary neoplasm of pancreas. The mass was well-demarcated with solid and cystic necrosis components. In the female patient, a large hematoma was found. Gross findings revealed apparent encapsulation, cystic degeneration and hemorrhagic necrosis. Microscopically the tumors were characterized by distinctive solid and papillary patterns of cellular arrangement without local invasion. Both patients were discharged after surgery and followed up without any problem.

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Simultaneous Evaluation of Cellular Vitality and Drug Penetration in Multicellular Layers of Human Cancer Cells

  • Al-Abd Ahmed Mohammed;Lee Joo-Ho;Kuh Hyo-Jeong
    • Journal of Pharmaceutical Investigation
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    • 제36권5호
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    • pp.309-314
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    • 2006
  • The multicellular layers(MCL) of human cancer cells is a three dimensional(3D) in vitro model for human solid tumors which has been used primarily for the assessment of avascular penetration of anti-cancer drugs. For anti-cancer drugs with penetration problem, MCL represents a good experimental model that can provide clinically relevant data. Calcein-AM is a fluorescent dye that demonstrates the cellular vitality in a graded manner in cancer cell culture system. In the present study, we evaluated the use of calcein-AM for determination of anti-proliferative activity of anti-cancer agents in MCL model of DLD-1 human colorectal cancer cells. Optical sectioning of confocal imaging was compromised with photonic attenuation and penetration barrier in the deep layers of MCL. By contrast, fluorescent measurement on the cryo-sections provided a feasible alternative. Cold pre-incubation did not enhance the calcein-AM distribution to a significant degree in MCL of DLD-1 cells. However, the simultaneous determination of drug penetration and cellular vitality appeared to be possible in drug treated MCL. In conclusion, these data suggest that calcein-AM can be used for the simultaneous determination of drug-induced anti-proliferative effect and drug penetration in MCL model.

셀 다공구조를 갖는 Al2O3세라믹스의 제조 (Processing of Al2O3 Ceramics with a Porous Cellular Structure)

  • 임병구;이락형;하정수
    • 한국세라믹학회지
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    • 제44권10호
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    • pp.574-579
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    • 2007
  • Porous $Al_2O_3$ ceramics were prepared by the gelcasting foams method (a slurry foaming process) with acrylamide monomer. The foaming and gelation behavior was investigated with the parameters such as the type and concentration of surfactant, solid loading of slurry, and the concentrations of initiator and catalyst. Density, porosity, microstructure, and strength of the green and sintered samples were characterized. Of the four kinds of surfactants tested, Triton X-114 showed the highest foaming ability for the solid loading of 55-30 vol%. The gelation condition giving the idle time off min was found to set the foamed structure without significant bubble enlargement and liquid lamella thinning. The green samples were fairly strong and machinable and showed maximum strength of 2.4 MPa in diametral compression. The sintered samples showed densities of 10-36% theoretical (i.e. porosity 90-64%) with a highly interconnected network of spherical pores with sizes ranging from 30 to $600{\mu}m$. The pore size and connectivity increased but the cell strut thickness decreased with decreasing the solid loading. Flexural strength of 37.8-1.7 MPa was obtained for the sintered samples.

간암 줄기세포의 기원 (Cellular origin of liver cancer stem cells)

  • 은종렬
    • Journal of Yeungnam Medical Science
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    • 제32권1호
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    • pp.1-7
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    • 2015
  • Over several decades, a hierarchical cancer stem cell (CSC) model has been established in development of solid cancers, including hepatocellular carcinoma(HCC). In terms of this concept, HCCs originate from liver CSCs. Clinically HCCs show a wide range of manifestations from slow growth to very aggressive metastasis. One of the reasons may be that liver CSCs originate from different cells. This review describes the basic concept of CSCs and the cellular origin of liver CSCs.

확장금속망 공정으로 제작된 옥테트 트러스 다공질 금속 (I) - 압축 및 전단 특성 - (Modified Octet Truss Cellular Metals Fabricated by Expanding Metal Process (I) - Compression and Shear Properties -)

  • 주재황;이동석;전인수;강기주
    • 대한기계학회논문집A
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    • 제31권11호
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    • pp.1124-1130
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    • 2007
  • This paper presents a new way for fabricating sandwich plates with tetrahedral truss cores. The tetrahedral truss cores are manufactured through metal expanding and bending process and then brazed with solid face sheets. The properties of sandwich plates with the tetrahedral truss cores composed of a wrought steel SS41 under compression and shear loading have been investigated. Good agreement is observed between the measured and predicted peak strengths. Comparisons with normalized compressive strength for other cellular metals have indicated that the tetrahedral truss structures outperform aluminum open cell forms and woven core sandwich plates.

Anticancer Activity of Acacia nilotica (L.) Wild. Ex. Delile Subsp. indica Against Dalton's Ascitic Lymphoma Induced Solid and Ascitic Tumor Model

  • Sakthive, K.M.;Kannan, N.;Angeline, A.;Guruvayoorappan, C.
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권8호
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    • pp.3989-3995
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    • 2012
  • The aim of the present investigation was to evaluate the effect of A.nilotica extract against Dalton's ascitic lymphoma (DAL) induced solid and ascitic tumors in BALB/c mice. Experimental animals received A.nilotica extract (10 mg/kg.bw) intraperitoneally for 10 and 14 consecutive days before induction of solid and ascitic tumors, respectively. Treatment with A.nilotica extract significantly decreased the development of tumor and percentage increase in body weight when compared to DAL induced solid tumor control group, also increasing the life span, restoring the total white blood cell count and hemoglobin content and significantly decreasing the levels of serum aspartate transaminase (SGPT), alanine transaminase (SGOT), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT) and nitric oxide (NO) when compared to DAL induced ascitic tumor controls. The treatment also reduced significantly the cellular glutathione (GSH) and nitric oxide levels in treated animals. Histopathological studies also confirmed protective influence. The outcome of the present work indicates that A.nilotica extract could be used as natural anticancer agent for human health.