• 제목/요약/키워드: nodal region

검색결과 59건 처리시간 0.022초

절점 비활성화 기법을 적용한 나노-연속체 멀티스케일 해석 기법 (Nano-continuum multi scale analysis using node deactivation techniques)

  • 이승윤;조맹효
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2006년도 정기 학술대회 논문집
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    • pp.395-402
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    • 2006
  • In analyzing the nano-scale phenomena or behaviors of nano devices or materials, it is often desirable to deal with more atoms than can be treated only with a full atomistic simulation. However, even now, it is advisable to apply the atomistic simulation to the narrow region where the deformation field changes rapidly but to apply the conventional continuum model to the region far from that region. This equivalent continuum model can be formulated by applying the Cauchy-Born rule to the exact atomistic potential as in the quasicontinuum method. To couple the atomistic model with the equivalent continuum model, continuum displacements are conformed to the molecular displacements at the discrete positions of the atoms within the bridging domain. To satisfy the coupling constraints, we apply the Lagrange multiplier method. The continuum model in the bridging model should be applied on the region where the deformation field changes gradually. Then we can make the nodal spacing in the continuum model be much larger than the atomic spacing. In the first step, we generate the atomic-resolution mesh with the nodal spacing equal to the atomic spacing, and then we eliminate the nodal degrees of freedom adaptively using the node deactivation techniques. We eliminate more DOFs as the regions are more far from the atomistic region. Computing time and computational resources can be greatly reduced by the present node deactivation technique in multi scale analysis.

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PIV measurements of near wake behind a sinusoidal cylinder

  • Zhang W.;Daichin Daichin;Lee S. J.
    • 한국가시화정보학회:학술대회논문집
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    • 한국가시화정보학회 2003년도 추계학술대회 논문집
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    • pp.59-62
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    • 2003
  • The near wake behind a sinusoidal cylinder at Re=5200 has been investigated using DPIV system. The velocity fields, streamlines and vorticity contours of the mean flow were compared at the nodal, saddle and middle planes with those of a right circular cylinder. For the sinusoidal cylinder, the vortex core moves downstream and the vortex formation region is expanded in streamwise direction while suppressed in transverse direction at the nodal plane. At the saddle and the middle plane the vortex spread in both streamwise and transverse directions, forming the maximum vortex region at the saddle plane.

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Patterns of failure after the reduced volume approach for elective nodal irradiation in nasopharyngeal carcinoma

  • Seol, Ki Ho;Lee, Jeong Eun
    • Radiation Oncology Journal
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    • 제34권1호
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    • pp.10-17
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    • 2016
  • Purpose: To evaluate the patterns of nodal failure after radiotherapy (RT) with the reduced volume approach for elective neck nodal irradiation (ENI) in nasopharyngeal carcinoma (NPC). Materials and Methods: Fifty-six NPC patients who underwent definitive chemoradiotherapy with the reduced volume approach for ENI were reviewed. The ENI included retropharyngeal and level II lymph nodes, and only encompassed the echelon inferior to the involved level to eliminate the entire neck irradiation. Patients received either moderate hypofractionated intensity-modulated RT for a total of 72.6 Gy (49.5 Gy to elective nodal areas) or a conventional fractionated three-dimensional conformal RT for a total of 68.4-72 Gy (39.6-45 Gy to elective nodal areas). Patterns of failure, locoregional control, and survival were analyzed. Results: The median follow-up was 38 months (range, 3 to 80 months). The out-of-field nodal failure when omitting ENI was none. Three patients developed neck recurrences (one in-field recurrence in the 72.6 Gy irradiated nodal area and two in the elective irradiated region of 39.6 Gy). Overall disease failure at any site developed in 11 patients (19.6%). Among these, there were six local failures (10.7%), three regional failures (5.4%), and five distant metastases (8.9%). The 3-year locoregional control rate was 87.1%, and the distant failure-free rate was 90.4%; disease-free survival and overall survival at 3 years was 80% and 86.8%, respectively. Conclusion: No patient developed nodal failure in the omitted ENI site. Our investigation has demonstrated that the reduced volume approach for ENI appears to be a safe treatment approach in NPC.

Radiofrequency catheter ablation of atrioventricular nodal reentry tachycardia in children and adolescents: a single center experience

  • Hyun, Myung Chul
    • Clinical and Experimental Pediatrics
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    • 제60권12호
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    • pp.390-394
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    • 2017
  • Purpose: Atrioventricular nodal reentry tachycardia (AVNRT) is less common in pediatric patients than in adult patients. Thus, data for pediatric AVNRT patients are insufficient. Hence, we aimed to analyze the patient characteristics, treatment, and any recurrences in pediatric AVNRT patients. Methods: We reviewed the records of 50 pediatric AVNRT patients who had undergone radiofrequency catheter ablation (RFCA) between January 1998 and December 2016 at a single regional center. The patients were aged ${\leq}18years$. Results: Among 190 pediatric patients who underwent RFCA for tachyarrhythmia, 50 (26.3%; mean age, $13.4{\pm}2.6years$) were diagnosed as having AVNRT by electrophysiological study. Twenty-five patients (25 of 50, 50%) were male. Twenty patients (20 of 50, 40%) used beta-blockers before RFCA. All patients had no structural heart disease except 1 patient with valvular aortic stenosis and coarctation of the aorta. RFCA was performed using the anatomic approach under fluoroscopic guidance. The most common successfully ablated region was the midseptal region (25 of 50, 50%). Slow pathway (SP) ablation and SP modulation were performed in 43 and 6 patients, respectively. Complication occurred in 1 patient with complete atrioventricular block. During follow-up, 6 patients had recurrence of supraventricular tachycardia, as confirmed by electrocardiography. Among them, 5 underwent successful ablation at the first procedure. In 1 patient, induction failed during the first procedure. Conclusion: RFCA is safe and effective in pediatric AVNRT patients. However, further research is needed for establishing the endpoints of ablation in pediatric AVNRT patients and for identifying risk factors by evaluating data on AVNRT recurrence after RFCA.

서울시 쇼핑.위락 목적통행으로 본 지역체계 (A Regional System of Seoul in Terms of Trip for Shopping and Leisure)

  • 김가은;임태선;홍현철
    • 대한지리학회지
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    • 제48권4호
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    • pp.545-556
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    • 2013
  • 본 연구에서는 서울시 424개 단위지구의 쇼핑 위락통행의 결절지역을 설정하고 상층으로 연계되는 지역체계 특성을 도출하였다. 이를 위해 결절지역의 수직구조를 나타내는 고층인자분석을 이용하여 쇼핑 위락 통행을 분석한 결과, 쇼핑통행보다는 위락통행이 더 큰 비중을 차지하며 1차 계층의 각 결절지역은 주요 발착지가 중앙에 위치하고 인접한 주변 단위지구에 발지 또는 착지가 연계되는 패턴을 보인다. 인자의 고유치가 클수록 공간적 범위가 넓게 나타나며 외곽에 위치한다. 고층으로 갈수록 결절지역을 형성하는 공간적 범위가 넓게 나타나며, 3차 계층 이상에서 양극인자에 따른 비지적 연계와 강남 강북 간 연계가 확연해진다. 또한 일반적인 쇼핑 위락 중심지로 여겨지는 종로 중구, 강남구, 영등포구를 중심으로 하는 결절지역의 연계가 뚜렷하게 나타나지 않는다. 특히 종로 금천 결절지역은 2차 계층 이후 타 결절지역과의 독립성을 유지하면서 상층으로 연계된다.

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Flow visualization and analysis of wake behind a sinusoidal cylinder

  • Nguyen A.T.;Lee S. J.
    • 한국가시화정보학회:학술대회논문집
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    • 한국가시화정보학회 2003년도 추계학술대회 논문집
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    • pp.31-34
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    • 2003
  • The near wake behind a sinusoidal cylinder has been investigated quantitatively using hot-wire anemometer and qualitative. The mean velocity and turbulence intensity were measured in streamwise and spanwise direction. The results show that the wake in the saddle plane has a longer vortex formation region and rapid reversed flow than that in nodal plane. The elongated vortex formation region of sinusoidal cylinder is related with drag reduction. In addition, the flow visualized with particle tracing method support the flow characteristics of sinusoidal cylinder measured by hot-wire.

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Complete mitochondrial genome of Rotunda rotundapex Miyata & Kishida 1990 (Lepidoptera: Bombycidae), which was named as Bombyx shini Park & Sohn 2002

  • Park, Jeong Sun;Kim, Min Jee;Kim, Iksoo
    • International Journal of Industrial Entomology and Biomaterials
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    • 제44권2호
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    • pp.55-64
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    • 2022
  • Bombyx shini Park & Sohn, 2002 (Lepidoptera: Bombycidae), which was listed as an endemic species in South Korea has recently been renamed as the East Asian silk moth Rotunda rotundapex Miyata & Kishida, 1990 (Lepidoptera: Bombycidae). In this study, we sequenced the complete mitochondrial genome (mitogenome) of the R. rotundapex to announce genomic characteristics and to clarify its validity with a new name. The 15,294-bp long complete mitogenome comprises a typical set of genes [13 protein-coding genes (PCGs), 2 rRNA genes, and 22 tRNA genes] and one major noncoding, A + T-rich region, with an arrangement identical to that observed in most lepidopteran mitogenomes. The A/T content of the whole mitogenome was 79.22%; however, it varied among the regions/genes as follows: A + T-rich region, 91.62%; srRNA, 84.67%; lrRNA, 83.01%; tRNAs, 81.43%; and PCGs, 77.46%. Phylogenetic analyses of 35 species in the Bombycoidea superfamily showed the sister relationship between the families Sphingidae and Bombycidae s. str., with the higher nodal support [bootstrap support (BS) = 78%]. The Saturniidae was placed as the sister to the two families, but the nodal support for this relationship was low (BS = 53%). Current R. rotundapex was placed together with previously reported con-species with the highest nodal support, forming a separate clade from Bombyx, validating that B. shini can have a new genus name, Rotunda. However, the Korean R. rotundapex showed a substantial sequence divergence at 5.28% to that originated from an individual of type locality Taiwan in 1,459-bp of COI sequences. Considering such a high sequence divergence an additional study, which includes morphological and DNA barcoding data from further extensive distributional range maybe is needed for further robust taxonomic conclusion.

In vitro Multiplication of Haloxylon recurvum (Moq.) - a Plant for Saline Soil Reclamation

  • Dagla Harchand R.;Shekhawat N.S.
    • Journal of Plant Biotechnology
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    • 제7권3호
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    • pp.155-160
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    • 2005
  • Haloxylon recurvum (Locally known as Khar) is drought and salt tolerant plant of Thar Desert. This plant is a major biomass producer and has economic and ecological importance for the region. There is need for study on biology, propagation and genetic improvement for utilization of this plant for reclamation of saline soils. We report here on in vitro propagation of Haloxylon recurvum (Moq.) using nodal explant. Secretion of phenolic compound from explants was a major constraint for establishment of culture. This was checked by thorough washing and quick transfer of explant on fresh culture medium. Juvenile nodal explant with leaves was found suitable for culture establishment. Benzy-ladenine($4.0\;{\mu}M$) incorporated in Murashige and Skoog (MS) medium with additives (50 mg/L ascorbic acid and 25 mg/L each of adenine sulphate, arginine and citric acid) induced multiple shoots from nodal explant. Addition of $1.0\;{\mu}M$ naphthalene acetic acid (NAA) in combination with $4.0\;{\mu}M$ BAP improved the growth of axillary shoots. Further shoot amplification was achieved by repeated subculture of mother explants on fresh medium. Forty percent of the micropropagated shoots rooted on half-strength MS medium with $4.0\;{\mu}M$ indolebutyric acid (IBA) and 100 mg/L activated charcoal, at $28{\pm}2^{\circ}C$ and $60\%$ RH. Sixty percent of these plantlets were hardened in green house.

이하선에 발생한 비호지킨스 림프종 1예 (A Case of Non Hodgkin's Lymphoma of Parotid Gland)

  • 황준연;김희종;문석균;이세영
    • 대한두경부종양학회지
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    • 제23권2호
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    • pp.170-173
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    • 2007
  • About 20% of non-Hodgkin' lymphoma occur in the extra-nodal region in the head and neck area and more than half of extra-nodal lymphoma in the head and neck area involves the Waldeyer' ring. Malignant lymphoma arising in the parotid glands are relatively rare, although 90% of all salivary gland lymphomas, appear in parotid gland and are classified as extranodal non Hodgkin' lymphoma. We experienced one rare case of non-Hodgkin' lymphoma in the right parotid gland, with a painless swelling of the cheek region as the chief complaint. We treated with CHOP(cyclophosphamide, $750mg/m^2$ i.v. day1 ; doxorubicin, $50mg/m^2$ i.v. day 1 ; vincristine, $1.4mg/m^2$ i.v. day 1;prednisone, $50mg/m^2$ orally days 1 to 5. repeat every 21 days) and Rituximab combination therapy. We aimed to report here one case of non-Hodgkin' lymphoma in the right parotid gland with review of literature.

광역지방행정중심지(廣域地方行政中心地)의 선정(選定)을 위한 합리적(合理的) 입지기준(立地基準)에 관(關)한 연구(硏究) (A Study on the Reasonable Standard of Location;allocation for a new administrative center in provincial area)

  • 윤준상
    • 농촌지도와개발
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    • 제5권1호
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    • pp.93-102
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    • 1998
  • The objectives of the study were 1) to make the reasonable standard, 2) to select the objective and scientific method and process for the location-allocation of a new provincial capital city. The Main standard of location-allocation were suggested as follows ; 1) Integration of province 2) Convenience of Administration service 3) Accomodations of new provincial capital city 4) Balanced development by region. The validity of location-allocation were reviewed the population potentials and nodal accessibilities. The population potential was examined to find the maximum point of administrative demand, and the locationallocation model was examined to find the minimum point of the aggregated travel-cost to a proposed provincial government office. The nodal accessibilities measured in travel-time distance and actual values. Two major concerns in locating public facilities are efficiency and equity.

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