• Title/Summary/Keyword: Parameters Sensitivity

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Clinical Significance of Soluble Major Histocompatibility Complex Class I Chain-related A in Renal Cell Carcinoma Patients

  • Qiu, Yu;Zhao, Ya-Kun;Yuan, Gang-Jun;Zhu, Qing-Guo
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.10
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    • pp.5651-5655
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    • 2013
  • Objective: Major histocompatibility complex class I chain-related A (MICA) is a stress-inducible glycoprotein that can be shed as a soluble protein. This study was conducted to determine the expression of MICA in renal cell carcinoma (RCC) and examine the clinical relevance of soluble MICA (sMICA) in this disease. Methods: Immunohistochemistry and real-time PCR analyses were performed to assess the expression of MICA in 48 pairs of RCC and adjacent normal renal tissues. Serum levels of sMICA were measured in 48 RCC patients, 12 patients with benign renal tumors, and 20 healthy individuals. The correlations between sMICA levels and clinicopathological parameters were analyzed and the diagnostic performance of sMICA in RCC was evaluated. Results: RCCs exhibited elevated expression of MICA compared to adjacent normal tissues. Serum concentrations of sMICA were significantly greater in RCC patients ($348.5{\pm}32.5pg/ml$) than those with benign disease ($289.3{\pm}30.4pg/ml$) and healthy controls ($168.4{\pm}43.2pg/ml$) and significantly correlated with advanced tumor stage, lymph node metastasis, distant metastasis, vascular invasion, and higher histological grade. Using a cut-off point of 250 pg/ml, sMICA demonstrated a specificity and sensitivity of 63.2% and 75.6%, respectively, in distinguishing between RCC and benign renal tumors. Conclusion: MICA expression is upregulated in RCC and increased serum sMICA levels predict aggressive tumor behavior. However, the applicability of sMICA alone is limited in distinguishing RCC from benign renal tumors.

A Parametric Study on Tensile Stress of a Hybrid Floating Structure System (매개변수 연구를 통한 하이브리드형 부유식 구조물의 인장응력 발생 분석)

  • Zi, Goangseup;Lee, Seung-Jung;Kwak, Yeon-Min;Jeong, Youn
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.5B
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    • pp.313-320
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    • 2012
  • A hybrid floating structure system combined with pontoon and semi-submersible type modules is proposed. This new system can reduce tensile forces of bottom slabs which could cause fatal damage of concrete floating structures. We performed a parametric study on the dimensions of this new system and investigate the sensitivity of the parameters to the behavior. In order to investigate various cases efficiently, we developed a simple two-step static analysis method for the fluid-structure interaction. An optimum system is derived from the investigation of the analysis results, weights and drafts of the hybrid structure. This study shows that introducing this new system to concrete floating structures is an effective way to reduce the tensile force of the bottm slab of such a floating structure. Also, it was found that when the length of the semi-submersible module is about 15%, the behavior would be optimal in the considered case.

Investigation of influence of homogenization models on stability and dynamic of FGM plates on elastic foundations

  • Mehala, Tewfik;Belabed, Zakaria;Tounsi, Abdelouahed;Beg, O. Anwar
    • Geomechanics and Engineering
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    • v.16 no.3
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    • pp.257-271
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    • 2018
  • In this paper, the effect of the homogenization models on buckling and free vibration is presented for simply supported functionally graded plates (FGM) resting on elastic foundation. The majority of investigations developed in the last decade, explored the Voigt homogenization model to predict the effective proprieties of functionally graded materials at the macroscopic-scale for FGM mechanical behavior. For this reason, various models have been used to derive the effective proprieties of FGMs and simulate thereby their effects on the buckling and free vibration of FGM plates based on comparative studies that may differ in terms of several parameters. The refined plate theory, as used in this paper, is based on dividing the transverse displacement into both bending and shear components. This leads to a reduction in the number of unknowns and governing equations. Furthermore the present formulation utilizes a sinusoidal variation of displacement field across the thickness, and satisfies the stress-free boundary conditions on the upper and lower surfaces of the plate without requiring any shear correction factor. Equations of motion are derived from Hamilton's principle. Analytical solutions for the buckling and free vibration analysis are obtained for simply supported plates. The obtained results are compared with those predicted by other plate theories. This study shows the sensitivity of the obtained results to different homogenization models and that the results generated may vary considerably from one theory to another. Comprehensive visualization of results is provided. The analysis is relevant to aerospace, nuclear, civil and other structures.

Stock Assessment of the Southern Bluefin Tuna Thunnus maccoyii Using the MULTIFAN-CL Model (MULTIFAN-CL 모델을 이용한 남방참다랑어 Thunnus maccoyii의 자원 평가)

  • Kwon, You-Jung;Moon, Dae-Yeon;Zhang, Chang-Ik;Koh, Jeong-Rack
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.40 no.6
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    • pp.367-373
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    • 2007
  • We assessed the stock of the southern bluefin tuna (SBT, Thunnus maccoyii) by applying the MULTIFAN-CL model. The model is spatially disaggregated, with the population and fisheries stratified into a number of regions within the overall stock range. Catch, effort, length-frequency, and tagging data from 1965 to 2003 were stratified by three regions and four quarters (Jan-Mar, Apr-Jun, Jul-Sept and Oct-Dec). These data were used to estimate the instantaneous fishing mortality (F), biomass, spawning biomass, recruitment, and so on. The Commission for the Conservation of Southern Bluefin Tuna (CCSBT) used only Japanese data and did not consider migration for the SBT stock assessment. By contrast, we used Japanese, Australian, New Zealand, Taiwanese, and Korean data, and considered migration. As a result, the estimated annual average F of all age classes was 0.073/yr and the F of age class 6-10 was the highest. The results also showed that the biomass and recruitment of SBT had declined significantly after 1965. Compared with the CCSBT results, the estimated spawning biomass in this study was lower and more uncertain. However, we will conduct a sensitivity analysis to get more accurate biological parameters and results. In addition, we need to use the bootstrap resampling method to quantify the uncertainty.

A study on the Dynamic Behavior Enhancement of the Korean High-speed Train (고속열차의 주행동특성 개선에 관한 연구)

  • Jeon, Chang-Sung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.10
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    • pp.81-87
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    • 2017
  • This paper describes the dynamic behavior and enhancement of Korean high-speed trains. The tail vibration reduction method of the yaw damper installation method change, which was derived from previous research, was applied to the running test of high-speed train. In addition, the vibration reduction method for the entire vehicle was derived by a numerical method and its effect was confirmed by a running test. The improved design was applied to the double-deck high-speed train coaches and the commissioning proceeded without problems in dynamic behavior. Sensitivity analysis of the suspension parameters affecting the critical speed of Korean next-generation high-speed trains was performed and four design variables that greatly affected the critical speed were derived. These were in the order of the primary elastic joint x-directional stiffness, the secondary yaw damper series stiffness, the secondary lateral damper damping coefficient, and the carbody damper damping coefficient. By optimizing the design variables, the suspension parameter that improves the critical speed by 23.3% can be used in the commercial designs of Korean next-generation high-speed trains.

Expression of Tumor Necrosis Factor Receptor-associated Factor 6 in Lung Cancer Tissues

  • Zhang, Xiu-Ling;Dang, Yi-Wu;Li, Ping;Rong, Min-Hua;Hou, Xin-Xi;Luo, Dian-Zhong;Chen, Gang
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.24
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    • pp.10591-10596
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    • 2015
  • Background: Tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) has been reported to be associated with the development of various cancers. However, the role of TRAF6 in lung cancer remains unclear. Objective: To explore the expression and clinicopathological significance of TRAF6 protein in lung cancer tissues. Materials and Methods: Three hundred and sixty-five lung cancer samples and thirty normal lung tissues were constructed into 3 microarrays. The expression of TRAF6 protein was determined using immunohistochemistry (IHC). Furthermore, correlations between the expression of TRAF6 and clinicopathological parameters were investigated. Results: The expression of TRAF6 in total lung cancer tissues (365 cases), as well as in small cell lung cancer (SCLC, 26 cases) and non-small cell lung cancer (NSCLC, 339 cases) was significantly higher compared with that in normal lung tissues. The ROC curve showed that the area under curve of TRAF6 was 0.663 (95%CI 0.570~0.756) for lung cancer. The diagnostic sensitivity and specificity of TRAF6 were 52.6% and 80%, respectively. In addition, the expression of TRAF6 was correlated with clinical TNM stage, tumor size and lymph node metastasis in all lung cancers. Consistent correlations were also observed for NSCLCs. Conclusions: TRAF6 might be an oncogene and the expression of TRAF6 protein is related to the progression of lung cancer. Thus, TRAF6 might become a target for diagnosis and gene therapy for lung cancer patients.

Accuracy Evaluation of DEM Produced by using KOMPSAT-5 InSAR Image (KOMPSAT 5호 InSAR영상을 이용한 DEM제작 정확도 평가)

  • Han, Seung-Hee
    • Journal of Cadastre & Land InformatiX
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    • v.47 no.2
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    • pp.39-47
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    • 2017
  • The SAR payload of the KOMPSAT-5 is equipped with an X-band (9.66GHz) microwave-based sensor. Especially, since it has a fixed antenna that can be electronically steered with respect to the azimuth and elevation planes, various applications are expected. This study evaluates the production performance and the accuracy of the DEM by producing DEM using the HR and UH mode images of KOMPSAT-5. To evaluate the production performance of the DEM, the sensitivity of DEM was assessed through a baseline analysis and $2{\pi}$ ambiguity; it was found to have good production performance. In addition, to evaluate the accuracy of the produced DEM, 30 check points were compared with SRTM data. As a result, STDEV ${\pm}15-20m$ accuracy was obtained. If the accuracy of the DEM is improved by adjusting the parameters of the filtering method or phase unwrapping method in the future, it will be possible to widely use the KOMPSAT-5 image for environmental and disaster monitoring.

Study on the Calculation Method of Design Flood Discharge of Dam (댐 설계홍수량 산정방법에 관한 연구)

  • Lee, Jai-Hong;Moon, Young-Il;Beck, Yoo-Hyun;Jang, Kwang-Jin
    • Proceedings of the Korea Water Resources Association Conference
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    • 2011.05a
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    • pp.277-281
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    • 2011
  • In this study, past method and recent method for flood discharge with domestic multi-purpose dams in Korea were compared and analyzed with respect to the scale of watershed. Rainfall depth, temporal distribution, effective rainfall, rainfall-runoff model, parameter estimation and base flow were selected as the principal factors affecting flood discharge and effects on flood discharge were analyzed quantitatively by using sensitivity analysis. The results showed that the flood discharges calculated by past and recent method increased and decreased with a wide range of discharge with respect to the scale of watershed. The reason for decrease of flood discharge is the exchange of temporal distribution pattern of rainfall and the principal reason for increase of flood discharge are the increase of rainfall depth by unusual weather phenomena and the difference of estimation method of parameters of unit hydrograph.

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Anti-proliferative Effect of Paclitaxel in Multicellular Layers of Human Cancer Cells (다층 배양된 암세포에서 파크리탁셀의 항증식효과 분석)

  • Kang, Choon-Mo;Lee, Joo-Ho;Cha, Jung-Ho;Kuh, Hyo-Jeong
    • Journal of Pharmaceutical Investigation
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    • v.36 no.1
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    • pp.1-9
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    • 2006
  • Human solid tumors exhibit a multicellular resistance (MCR) resulting from limited drug penetration and decreased sensitivity of tumor cells when interacting with their microenvironments. Multicellular cultures represent solid tumor condition in vivo and provide clinically relevant data. There is little data on antitumor effect of paclitaxel (PTX) in multicellular cultures although its MCR has been demonstrated. In the present study, we evaluated antiproliferative effects of PTX in multicellular layers (MCL) of DLD-1 human colorectal carcinoma cells. BrdU labeling index (LI), thickness of MCL, cell cycle distribution and cellular uptake of calcein were measured before and after exposure to PTX at 0.1 to 50 ${\mu}M$ for 24, 48 and 72 hrs. BrdU LI and thickness of MCL showed a concentration- and time-dependent decrease and the changes in both parameters were similar, i.e., 34.2% and 40.6% decrease in BrdU LI and thickness, respectively, when exposed to $50\;{\mu}M$ for 72 hr. The DLD-1 cells grown in MCL showed increase in $%G_{0}/G_{1}$ and resistance to cell cycle arrest and apoptosis compared to monolayers. Calcein uptake in MCL did not change upon PTX exposure, indicating technical problems in multicellular system. Overall, these data indicate that antitumor activity of PTX may be limited in human solid tumors (a multicellular system) and MCL may be an appropriate model to study further pharmacodynamics of PTX.

A Numerical Study on Sensitivity of Acoustic Response to Pressure Oscillations in Liquid Rocket Engine (압력진동에 대한 액체 로켓엔진의 음향 응답의 민감도에 관한 수치적 연구)

  • Sohn, Chae-Hoon
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.30 no.5
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    • pp.79-87
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    • 2002
  • Acoustic responses to pressure oscillations in axisymmetric combustion chamber are numerically investigated to examine the qualitative trend of acoustic instability in liquid rocket engine. Chamber operating condition and excitation frequency of oscillating pressure are selected as exciting parameters of acoustic instability. Artificial perturbation is simulated by total-pressure oscillation with sine wave at chamber inlet. Many approximations and simplifications are introduced without losing the essence of acoustic pressure response. First, steady-state solution for each operating condition is obtained and next, transient analysis is conducted. Depending on operating condition and excitation frequency, the distinct response characteristics are brought. Weak-strength flames and high-frequency excitation tend to cause sensitive acoustic pressure response leading to unstable pressure field. These results are analyzed based on the correlation with acoustic pressure responses from the previous works adopting laminar flamelet model.