• 제목, 요약, 키워드: SPT

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유연한 점토-폴리(비닐 알코올) 하이브리드 필름의 특성 연구: 열적.광학적 성질, 모폴로지, 및 가스 투과성 (Characterizations of Flexible Clay-PVA Hybrid Films: Thermo-optical Properties, Morphology, and Gas Permeability)

  • 신지은;함미란;김정철;장진해
    • 폴리머
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    • v.35 no.5
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    • pp.402-408
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    • 2011
  • $Na^+$-사포나이트(saponite, SPT) 필름의 유연성을 향상시키기 위해 수용성 고분자인 폴리(비닐 알코올)(poly(vinyl alcohol); PVA)을 다양한 함량(0~10 wt%)으로 사용하여 용액 삽입방법을 통해 SPT 하이브리드 필름을 제조하였다. 본 논문에서는 SPT 하이브리드 필름의 열적 광학적 성질, 모폴로지, 및 가스 투과성 등을 조사하였다. PVA 농도에 따른 SPT 하이브리드 필름의 성질들은 X-선 회절도(XRD), 전계방사형 주사전자현미경(FE-SEM), 시차주사 열량계(DSC), 열중량 분석기(TGA), 열기계 분석기(TMA), 자외선-가시광선(UV-vis.) 흡광도기, 및 산소투과($O_2$TR) 측정기 등을 통해 조사하였다. SPT 하이브리드 필름의 성질들은 PVA의 무게% 농도에 따라 많은 영향을 받았으며, 적은 양의 PVA도 SPT 하이브리드 필름의 유연성을 증가시키기에 충분하였다.

대심도 연약지반에 항타매입된 PHC 말뚝의 선단지지력을 위한 CPT와 SPT법의 적용성 분석 (Applicability of PDA and SPT-based methods for Toe Bearing Capacity of PHC Piles Driven in the Thick Deltaic Deposits)

  • ;정성교;김성렬
    • 한국지반공학회:학술대회논문집
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    • pp.713-720
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    • 2008
  • 본 연구는 낙동강 하구 대심도 연약지반에 항타관입된 PHC 말뚝에 대하여 SPT 지지력 공식으로 부터 계산된 선단지지력 값과 PDA 시험에서 얻어진 선단지지력 측정값을 비교하였다. 또한, SPT N값이 50이 넘는 경우에 대하여는 N값과 롯드 관입깊이의 선형관계를 가정하여 30cm 관입깊이에 해당하는 N값을 적용한 경우와 CPT $q_c$와의 상관성을 이용하여 $q_c$값으로부터 N값을 산정한 경우의 2가지 분석을 수행하였다. 그 결과, 본 연구에서 적용한 SPT 지지력 공식 모두 측정된 선단지지력 값과 차이가 났으며, SPT 지지력 공식은 대심도 연약지반에 항타 근입된 말뚝에 대하여 실제적인 설계를 수행할 때 신뢰하기 어려운 것으로 나타났다. 또한, N>50인 경우에 대하여 N값과 롯드 관입깊이의 선형관계를 적용하는 것은 지지력을 매우 과대평가하는 것으로 나타났다.

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와편모조류 시스트 분리를 위한 Panning 방법과 SPT 용액방법의 비교 (Comparison of Panning and Sodium Polytungstate Methods for Separating Dinoflagellate Cysts)

  • 강윤자;문창호;조현진
    • 한국수산과학회지
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    • v.41 no.3
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    • pp.228-231
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    • 2008
  • Two methods for separating dinoflagellate cysts from marine sediments were compared: panning and sodium polytungstate (SPT). After pretreatment with the SPT solution, Protoperidinium species had a high germination rate and cell growth rate. The germinated cells grew continuously, even in a low nutrient environment. Alexandrium cysts did not germinate, because their germination is usually active in winter. Using SPT solution, the separation process was easier, quicker, and caused much less eye fatigue than the panning method. Therefore, SPT solution offers a convenient way of pretreating dinoflagellate cysts for separation and analysis.

천식모델생쥐에서 선폐탕(宣肺湯)의 면역조절 효과 (Effects of Seonpye-tang on OVA-Induced Asthmatic Mice)

  • 이주관;박양춘
    • 동의생리병리학회지
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    • v.23 no.2
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    • pp.457-463
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    • 2009
  • This study aimed to evaluate the anti-asthmatic effects of Seonpye-tang (SPT) using OVA-induced asthmatic mice model. Scavenging activity of SPT on DPPH free radical and SOD-like activity of SPT were measured at final concentration 62.5, 125, 250, 500 (${\mu}g/m{\ell}$), RBL-2H3 cells were treated with DNP IgE for 24hr, and treated with SPT (1, 10, 100 ${\mu}g/m{\ell}$) for 1hr, followed by treatment with DNP-HSA for 1hr at $37^{\circ}C$. The level of IL-4 and TNF-${\alpha}$ were measured by ELISA. Asthmatic mice model was conducted by repeated challenge of OVA using C57BL/6 mice. Each group was treated with distilled water, SPT (400 mg/kg and 200 mg/kg) extract or cyclosporin A (10 mg/kg) for the later 8 weeks. Immune cells subpopulation, eotaxin, IL-5 and TNF-${\alpha}$ in BALF were analyzed. SPT dose-dependently increased Scavenging activity on DPPH free radical and SOD-like activity. SPT significantly ameliorated the increase of total cells number and eosinophil including of immune cell subpopulation of $CD3^+/CD69^+$, $CCR3^+$, $B220^+/CD22^+$, $B220^+/CD45^+$ and $B220^+/IgE^+$ cells in BALF comparing to control group. Eotaxin and IL-5 level in BALF were significantly decreased by SPT. These results strongly suggest that SPT would be a effective candidate for herbal-originated anti-asthmatic drug. However, this drug should be further studied for characterization of the accurate action and underlying mechanisms using variant disease model in the future.

선방패독탕(仙方敗毒湯)과 시경청폐탕(柴梗淸肺湯)이 NCI-H292 세포에서 PMA로 유발된 기도뮤신의 생성과 MUC5AC 발현에 미치는 영향 (Effects of Seonbangpaedok-tang and Sigyeongcheongpye-tang on PMA-induced Production of Airway Mucin and Expression of MUC5AC)

  • 남태흥;박양춘
    • 대한한의학회지
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    • v.29 no.4
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    • pp.123-132
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    • 2008
  • Objective: In this study, the author tried to investigate whether revised Seonbangpaedok-tang (SPT) and Sigyeongcheongpye-tang (SCT) significantly effects both PMA-induced mucin production and MUC5AC gene expression from airway epithelial cells. Objective: In this study, the author tried to investigate whether revised Seonbangpaedok-tang (SPT) and Sigyeongcheongpye-tang (SCT) significantly affects both PMA-induced mucin production and MUC5AC gene expression from airway epithelial cells. Materials and Methods: Confluent NCI-H292 cells were pretreated for 30 min in the presence of SPT and SCT and treated with PMA (10 ng/$m{\ell}$), to assess the effects of the agents on PMA-induced mucin production by enzyme-linked immunosorbent assay (ELISA). Also, the effects of the agents on PMA-induced MUC5AC gene expression from the same cells were investigated. Possible cytotoxicities of the agent were assessed by measuring the rate of survival and proliferation of NCI-H292 cells after treatment of agents during 48 hrs. Results: (1) SPT and SCT did not show significant cytotoxicity to NCI-H292 cells; (2) SPT significantly inhibitedthe expression levels of PMA-induced MUC5AC gene in NCI-H292 cells. SCT slightly decreased the expression levels of PMA-induced MUC5AC gene; (3) SPT significantly decreased PMA-induced mucin production from NCI-H292 cells. However, SCT did not affect mucin production. Conclusion: Theseresults suggest that SPT can not only affect the production of mucin but also the expression of the mucin gene and this explains the traditional use of SPT in oriental medicine. The effects of SPT and SCT with their components should be further investigated using animal experimental models that reflect pathophysiology of airway diseases via ongoing studies.

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폴리(비닐 알코올)/사포나이트 나노 복합체 필름 및 연신된 필름의 열적 성질, 모폴로지, 광학 투명성, 및 기체 투과성 (Thermal Property, Morphology, Optical Transparency, and Gas Permeability of PVA/SPT Nanocomposite Films and Equi-biaxial Stretching Films)

  • 함미란;김정철;장진해
    • 폴리머
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    • v.37 no.5
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    • pp.579-586
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    • 2013
  • 용액 삽입법을 이용하여 다양한 함량의 사포나이트(SPT) 점토를 포함한 폴리(비닐 알코올)(poly(vinyl alcohol), PVA) 나노 복합체 필름을 제조하였다. SPT를 0에서 10 wt%까지 첨가한 PVA 나노 복합체 필름들의 열적 특성, 모폴로지, 광학 투명성 및 기체 투과성에 대해 조사하였다. 특히 5 wt% SPT 포함한 PVA 복합체 필름이 매우 우수한 열적 특성과 기체 차단성을 나타내었다. 5 wt% SPT 포함된 복합체 필름을 연신율에 따라 150에서 250%까지 이축 연신하였고, 이축 연신율에 따른 점토 분산성, 광학적 특성 및 기체 투과성에 대한 조사를 하였다. 다양한 비로 이축 연신한 PVA 나노 복합체 필름은 우수한 광학 투명성과 산소 차단성을 보였다.

표준관입시험 자동기록장치의 N치 특성 연구 (A Study on the N Values Characteristics of Automatic Recording System of SPT)

  • 윤원섭;박면규;한재운;신승구;채영수
    • 한국지반공학회:학술대회논문집
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    • pp.1168-1176
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    • 2010
  • Currently drilling investigation and the SPT in parallel not only organization and peculation sincerity quality historian of test to be old the data was abundant with the site ground investigation test which is representative and the research of empirical formula in compliance with many scholar was accomplished and was come. The data which is like this wide is used with geotechnical engineering data of plan and space-time of the field which is various. SPT with tentative voluntary skillful degree record method of variety and technical expert of equipment, according to site conditional is consistent the quality of ground condition but cannot be made to show there is a tendency and specially the point whose is difficult actually accurately to follow the interval which decides in quality as a matter of tentative standard of drill and the test in parallel and a tentative method exists. From the research which sees consequently also the skill of variety and technical expert of equipment of SPT, strong point of the SPT automation logger will be able to complement the problem point of quality etc. of site condition under comparison analyzing should have been boiled about SPT of existing and tentative methods and N-value.

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An Efficient Algorithm for Dynamic Shortest Path Tree Update in Network Routing

  • Xiao, Bin;Cao, Jiannong;Shao, Zili;Sha, Edwin H.M.
    • Journal of Communications and Networks
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    • v.9 no.4
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    • pp.499-510
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    • 2007
  • Shortest path tree(SPT) construction is essential in high performance routing in an interior network using link state protocols. When some links have new state values, SPTs may be rebuilt, but the total rebuilding of the SPT in a static way for a large computer network is not only computationally expensive, unnecessary modifications can cause routing table instability. This paper presents a new update algorithm, dynamic shortest path tree(DSPT) that is computationally economical and that maintains the unmodified nodes mostly from an old SPT to a new SPT. The proposed algorithm reduces redundancy using a dynamic update approach where an edge becomes the significant edge when it is extracted from a built edge list Q. The average number of significant edges are identified through probability analysis based on an arbitrary tree structure. An update derived from significant edges is more efficient because the DSPT algorithm neglect most other redundant edges that do not participate in the construction of a new SPT. Our complexity analysis and experimental results show that DSPT is faster than other known methods. It can also be extended to solve the SPT updating problem in a graph with negative weight edges.

지반의 전단파 속도 도출을 위한 SPT 업홀 기법의 확립 및 검증 (Establishment and Verification of SPT-uphole method for Evaluating Shearwave Velocity of a site)

  • 방은석;김정호;서원석;김동수
    • 한국지반공학회:학술대회논문집
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    • pp.142-152
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    • 2008
  • SPT-Uphole method was introduced for the evaluation of near subsurface shear wave velocity (Vs) profile. In SPT-Uphole method, SPT (Standard Penetration Test) which is common in geotechnical site investigation was used as a source and several surface geophones in line were used as receivers. 1D shearwave velocity profile can be obtained in the manner of downhole method, Vs distribution map which is the triangular shape around the boring point can be developed by tomography inversion. To obtain the exact travel time information of shear wave component, a procedure using the magnitude summation of vertical and horizontal components was used based on the evaluation of particle motion at the surface. It was verified that proposed method could give reliable Vs distribution map through the numerical study using the FEM (Finite Element Method) model. Finally, SPT-Uphole method was performed and the feasibility of proposed method was verified in the field.

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