• 제목/요약/키워드: cell arrangement

검색결과 253건 처리시간 0.026초

Effects of cp-Ti Surface Roughness and Directionality on Initial Cell Attachment Behaviors

  • Shin, Dong-Hoon;Chun, Sungsu;Ahn, Myun-Whan;Song, In-Hwan;Kim, Sukyoung
    • 대한금속재료학회지
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    • 제50권4호
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    • pp.338-343
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    • 2012
  • The early osseointegration of titanium (Ti) dental implants is related to the initial cell morphology. The morphology of the cells (mesenchymal stem cells, MSC) was observed on three different Ti disc surfaces, which were mechanically treated by polishing, blasting, and scratching. A non-directional surface (isotropic texture) was obtained by the blasting of HA grits on cp-Ti discs, and a unidirectional surface (anisotropic texture) was obtained by the scratching of SiC papers. The cell attachment and arrangement in the initial periods were quite similar, but those in the later periods were significantly affected by the texture of the cp-Ti discs. After 1 week, the blasted Ti discs showed non-directional arrangement or spreading of the cells, whereas the scratched cp-Ti discs showed unidirectional properties parallel to the direction of the scratched grooves on the surface. The surface roughness of the cp-Ti discs significantly affects cell proliferation. Cell proliferation on the blasted and scratched surfaces was about 60% and 40% higher compared to the control result (polishing group) after 1 week (P<0.05). Cell proliferation on the blasted and scratched surfaces after 1 week was slightly enhanced with increasing surface roughness. It is believed that the direction of cell attachment and arrangement is closely related to the surface texture of the substrate surfaces, but cell proliferation after a relatively long period of time is directly enhanced by the surface roughness, not by the surface texture.

GPU를 이용한 삼각형 집합의 외경계 계산 알고리즘 (GPU Algorithm for Outer Boundaries of a Triangle Set)

  • 경민호
    • 한국CDE학회논문집
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    • 제17권4호
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    • pp.262-273
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    • 2012
  • We present a novel GPU algorithm to compute outer cell boundaries of 3D arrangement subdivided by a given set of triangles. An outer cell boundary is defined as a 2-manifold surface consisting of subdivided polygons facing outward. Many geometric problems, such as Minkowski sum, sweep volume, lower/upper envelop, Bool operations, can be reduced to finding outer cell boundaries with specific properties. Computing outer cell boundaries, however, is a very time-consuming job and also is susceptible to numerical errors. To address these problems, we develop an algorithm based on GPU with a robust scheme combining interval arithmetic and multi-level precisions. The proposed algorithm is tested on Minkowski sum of several polygonal models, and shows 5-20 times speedup over an existing algorithm running on CPU.

The Characteristics of a Hydrogenated Amorphous Silicon Semitransparent Solar Cell When Applying n/i Buffer Layers

  • Lee, Da Jung;Yun, Sun Jin;Lee, Seong Hyun;Lim, Jung Wook
    • ETRI Journal
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    • 제35권4호
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    • pp.730-733
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    • 2013
  • In this work, buffer layers with various conditions are inserted at an n/i interface in hydrogenated amorphous silicon semitransparent solar cells. It is observed that the performance of a solar cell strongly depends on the arrangement and thickness of the buffer layer. When arranging buffer layers with various bandgaps in ascending order from the intrinsic layer to the n layer, a relatively high open circuit voltage and short circuit current are observed. In addition, the fill factors are improved, owing to an enhanced shunt resistance under every instance of the introduced n/i buffer layers. Among the various conditions during the arrangement of the buffer layers, a reverse V shape of the energy bandgap is found to be the most effective for high efficiency, which also exhibits intermediate transmittance among all samples. This is an inspiring result, enabling an independent control of the conversion efficiency and transmittance.

Three-dimensional analysis of the arrangement of microtubules of the outer segment in the ciliary-type photoreceptor cell in the Onchidium dorsal eye

  • Katagiri, Nobuko;Shimatani, Yuichi;Katagiri, Yasuo
    • Journal of Photoscience
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    • 제9권2호
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    • pp.284-286
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    • 2002
  • The inverted retina of the Onchidium dorsal eye (DE) is composed only of ciliary-type photoreceptor cells (CC's). The outer segment (OS) of the CC is a concentric lamellar structure consisting of many modified ciliary membranes and stains positively with anti-$\beta$-tubulin antibody. Near the base of the OS there are about 30 basal bodies each connecting individually to a cilium. The cilia are rod-shaped at the base, progressing upwards to a flattened sheet-like shape with increasing surface area. Three-dimensional analysis on serial sections demonstrates the ladle-shape of a modified cilium. Many modified cilia wrap around each other like the leaves of a cabbage. Nine pairs of microtubules (MT's) are located regularly in a ring at the base of the cilium, gradually losing their regular arrangement towards the periphery, where they separate into two subgroups that are contained within two swollen portions of a modified cilium. Within the CC of the Onchidium DE, MT's in the modified cilium exist as two poles extending longitudinally in a thin expanded ciliary membrane. This arrangement may support the photoreceptive OS and serve to maintain its structural integrity.

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건축물 자동 공간계획 프로그램 개발에 관한 연구 (A Study on the Automatic Architectural Space Design Computer Program)

  • 임명구
    • 한국디지털건축인테리어학회논문집
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    • 제7권1호
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    • pp.1-6
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    • 2007
  • In this study, we fill a person's shoes human knowledge use a computer fast and simple repetition in architecture design. this study are launched from a assumption that a optimized arrangement spaces are able to measure and gauge. but automatic space arrangement program is first step, we have a value that propose a differential cell space and valuation space and process of optimized space arrangement. the merits of this design process are as follows; 1. this program has a advantage high the building-to-land ratio land and business area in space design. 2.this program can design a economy building and calculate rent benefit and calculate cost of construction. 3. this program can adapt for digital GIS. this program can down cost in labor productivity. 5. a layman can design high level. the weak point of this design process are as follows; 1. the design product is simple box shape. 2. this program has a weak in large area and complicated land shape 3. complex use space design are difficult in this program.

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평판형 방전판을 갖는 2단식 전기집진기의 집진판 블록배열이 집진효율에 미치는 영향 (Effects of the Block Arrangement on the Collection Efficiency in the Two-Stage Electrostatic Precipitator with Charging Plate)

  • 박성호;박청연;김태권
    • 한국대기환경학회지
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    • 제16권6호
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    • pp.641-652
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    • 2000
  • The effect of block arrangement has been investigated on the particle deposition in the specified collecting cell of two-stage electrostatic precipitator by numerical analysis. Recirculation zone existed at the downstream of the block in the collecting cell, and the particles entering the recirculation zone were deposited on the collecting plate. Particle trajectory and deposition had considerably different phenomenon according to electrostatic and inertial effect, which depended on inlet mean velocity, electrostatic number, and particle diameter in the collecting cell. The total collection efficiency reached a minimum value through an interaction of electrostatic and inertial effect. In the computational domain, total collection efficiency for the case of two blocks in the computational domain was more than that of one block at the relative small electrostatic number. However as the block distance and inertial effect increased, the difference between the collection efficiency of two cases decreased. In the range of relatively small particle size total collection efficiency was always superior to particle collection efficiency that was predicted by Deutsch equation.

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다중 MPEG 비디오 전송을 위한 I-픽쳐 정렬 방안 (A Novel I-picture Arrangement Method for Multiple MPEG Video Transmission)

  • 박상현
    • 한국정보통신학회논문지
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    • 제9권2호
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    • pp.277-282
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    • 2005
  • VBR (variable bit rate) MPEG 비디오 트래픽은 COP(group of pictures)의 시작인 I-픽쳐에서는 다른 픽쳐들보다 매우 큰 양의 트래픽이 발생하기 때문에 COP 구조에 따라 주기적 형태의 트래픽 발생 패턴을 가진다. 따라서, VBR MPEG 비디오 정보원이 다중화 될 때 I-픽쳐들의 시작 시간 배열은 다중화기의 셀 손실 특성에 큰 영향을 준다. 본 논문에서는 VBR MPEG 비디오 정보원들이 하나의 전송로로 전송되기 위해 다중화 될 때 다중화기에서의 셀 손실률을 최소화하기 위해서 각 비디오 정보원의 I-픽쳐 시작시간들을 배열하는 방안을 제시한다. 제안하는 방안에서는 정확한 I-픽쳐 시작 시간을 효과적으로 찾기 위해 다중화된 정보원의 셀 도착률이 전송로의 용량을 초과하는 확률을 이용하였다. 모의 실험을 통해 제안하는 방법이 기존의 방법들 보다 최적으로 비디오 정보원들을 다중화 시키는 것을 보였다.

Nicotiana tabacum과 Petunia inflata의 전기적 원형질체융합에 의한 속간 체세포 잡종의 생성 (Intergeneric Somatic Hybrids by Electrofusion of Protoplasts Between Nicotiana tabacum and Petunia inflata)

  • 김준철
    • Journal of Plant Biology
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    • 제30권1호
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    • pp.1-9
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    • 1987
  • Leaf mesophyll protoplasts of Nicotiana tabacum (nitrate reductase deficient mutant) were fused with cell suspension protoplasts of albino Petunia inflata in an electric field. Hybrid cell colonies were selected for nitrate reductase proficiency and chlorophyll synthesis. Five hybrid plant lines, regenerated from the selected calli lines, were analysed by electrophoresis, number of chromosomes and morphological characters. Somtic hybrid plants showed both parent patterns in the isozymesof isoleucine aminopeptidase and esterase. The hybrids had the expected chromosome number of 62 and exhibited an intermediate floral morphology when compared with the parents, but plant height and leaf arrangement were similar to N. tabacum.

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