• Title/Summary/Keyword: Key Characteristics

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Meta-analysis of Circulating Tumor Cells as a Prognostic Marker in Lung Cancer

  • Ma, Xue-Lei;Xiao, Zhi-Lan;Liu, Lei;Liu, Xiao-Xiao;Nie, Wen;Li, Ping;Chen, Nian-Yong;Wei, Yu-Quan
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1137-1144
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    • 2012
  • Introduction: Recent studies have shown that circulating tumor cells (CTCs) play potential roles as diagnostic and prognostic biomarkers with various cancer types. The aim of this study was to comprehensively and quantitatively summarize the evidence for the use of CTCs to predict the survival outcome of lung cancer patients. Materials and Methods: Relevant literature was identified using Medline and EMBASE. Patients' clinical characteristics, overall survival (OS) and progression-free survival (PFS) together with CTC positive rates at different time points (before, during and after treatment) were extracted. A meta-analysis was performed to clarify the prognostic role of CTCs and the correlation between the CTC appearance and clinical characteristics. Results: A total of 12 articles containing survival outcomes and clinical characteristics and 15 articles containing only clinical characteristics were included for the global meta-analysis. The hazard ratio (HR) for OS predicted by pro-treatment CTCs was 2.61 [1.82, 3.74], while the HR for PFS was 2.37 [1.41, 3.99]. The HR for OS predicted by post-treatment CTCs was 4.19 [2.92, 6.00], while the HR for PFS was 4.97 [3.05, 8.11]. Subgroup analyses were conducted according to histological classification and detection method. Odds ratio (OR) showed the appearance of pro-treatment CTCs correlated with the lymph node status, distant metastasis, and TNM staging, while post-treatment CTCs correlated with TNM staging only. Conclusion: Detection of CTCs in the peripheral blood indicates a poor prognosis in patients with lung cancer.

An Experimental Study of the Improvement of Driveability in Vehicle Acceleration Mode (차량 급가속시 운전성 개선을 위한 실험적 연구)

  • 송해박;최윤준;이종화;조한승;조남효
    • Transactions of the Korean Society of Automotive Engineers
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    • v.9 no.6
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    • pp.65-75
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    • 2001
  • Modern vehicles require a high degree of refinement including good driveability. Vehicle driveability, which becomes a key decisive factor f3r marketability, is affected by many parameters such as engine control and the dynamic characteristics in drive lines. Therefore engine and drive train characteristics should be considered to achieve a well balanced vehicle response simultaneously. This paper describes experimental procedures which have been developed to measure engine torque and investigate shuffle characteristics. To analyze the vehicle dynamic behavior, fractional torques and inertia mass moment of engine, and drive train were measured. Shuffle characteristics during tip-in condition were investigated in an experimental vehicle at 2nd and 3rd gear stages. It was found that the shuffle characteristics were caused by sudden changes of engine torque and have a different vibration frequency with gear stage variation. Inertia mass moment of engine including flywheel rotation showed a key factor for the shuffle characteristics.

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A Study of Implementing Knowledge Management (KM) in Construction Domain (건설업 지식경영체제 구축에 관한 연구)

  • Park Min-Kyoo;Baek Jong-kun;Kim Dae-Ho;Kim Jae-Jun
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.273-278
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    • 2001
  • Since its introduction in mid 1990s, Financial Crisis in Korea, knowledge management (KM) has been considered as a new, optimal way of corporate management style. And a large number of researches, either theoretically or empirically, were carried out in order to find out what the key success factors will be in common. However, though key success factors are extracted, it can hardly be a successful project if those are not well matched for the unique industry characteristics, still more in construction industry. Even we can find some KM precedents in construction industry, it can hardly be revealed how far they exerted themselves in order to match key factors with industry characteristics. Hence, at the dawn of implementing KM, this research work will scrutinize key success factors (KSFs) derived from previous studies and funnel those KSFs into construction domain. Then rearranged KSFs will be proposed with each key issues. Therefore, this article can contribute to setting strategies for KM in construction sector.

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Modeling and Analysis of a Novel Two-Axis Rotary Electromagnetic Actuator for Fast Steering Mirror

  • Long, Yongjun;Wang, Chunlei;Dai, Xin;Wei, Xiaohui;Wang, Shigang
    • Journal of Magnetics
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    • v.19 no.2
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    • pp.130-139
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    • 2014
  • This paper focuses on the modeling and analysis a novel two-axis rotary normal-stress electromagnetic actuator with compact structure for fast steering mirror (FSM). The actuator has high force density similar to a solenoid, but its torque output is nearly a linear function of both its driving current and rotation angle, showing that the actuator is ideal for FSM. In addition, the actuator is designed with a new cross topology armature and no additional axial force is generated when the actuator works. With flux leakage being involved in the actuator modeling properly, an accurate analytical model of the actuator, which shows the actuator's linear characteristics, is obtained via the commonly used equivalent magnetic circuit method. Finally, numerical simulation is presented to validate the analytical actuator model. It is shown that the analytical results are in a good agreement with the simulation results.

Probabilistic and spectral modelling of dynamic wind effects of quayside container cranes

  • Su, Ning;Peng, Shitao;Hong, Ningning;Wu, Xiaotong;Chen, Yunyue
    • Wind and Structures
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    • v.30 no.4
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    • pp.405-421
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    • 2020
  • Quayside container cranes are important delivery machineries located in the most frontiers of container terminals, where strong wind attacks happen occasionally. Since the previous researches on quayside container cranes mainly focused on the mean wind load and static response characteristics, the fluctuating wind load and dynamic response characteristics require further investigations. In the present study, the aerodynamic wind loads on quayside container cranes were obtained from wind tunnel tests. The probabilistic and spectral models of the fluctuating aerodynamic loads were established. Then the joint probabilistic distributions of dynamic wind-induced responses were derived theoretically based on a series of Gaussian and independent assumption of resonant components. Finally, the results were validated by time domain analysis using wind tunnel data. It is concluded that the assumptions are acceptable. And the presented approach can estimate peak dynamic sliding force, overturning moments and leg uplifts of quayside container cranes effectively and efficiently.

Analysis and Characterization of Glutathione Peroxidases in an Environmental Microbiome and Isolated Bacterial Microorganisms

  • Yun-Juan Bao;Qi Zhou;Xuejing Yu;Xiaolan Yu;Francis J. Castellino
    • Journal of Microbiology and Biotechnology
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    • v.33 no.3
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    • pp.299-309
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    • 2023
  • Glutathione peroxidases (Gpx) are a group of antioxidant enzymes that protect cells or tissues against damage from reactive oxygen species (ROS). The Gpx proteins identified in mammals exhibit high catalytic activity toward glutathione (GSH). In contrast, a variety of non-mammalian Gpx proteins from diverse organisms, including fungi, plants, insects, and rodent parasites, show specificity for thioredoxin (TRX) rather than GSH and are designated as TRX-dependent peroxiredoxins. However, the study of the properties of Gpx in the environmental microbiome or isolated bacteria is limited. In this study, we analyzed the Gpx sequences, identified the characteristics of sequences and structures, and found that the environmental microbiome Gpx proteins should be classified as TRX-dependent, Gpx-like peroxiredoxins. This classification is based on the following three items of evidence: i) the conservation of the peroxidatic Cys residue; ii) the existence and conservation of the resolving Cys residue that forms the disulfide bond with the peroxidatic cysteine; and iii) the absence of dimeric and tetrameric interface domains. The conservation/divergence pattern of all known bacterial Gpx-like proteins in public databases shows that they share common characteristics with that from the environmental microbiome and are also TRX-dependent. Moreover, phylogenetic analysis shows that the bacterial Gpx-like proteins exhibit a star-like radiating phylogenetic structure forming a highly diverse genetic pool of TRX-dependent, Gpx-like peroxidases.

Wind characteristics at Sutong Bridge site using 8-year field measurement data

  • Xu, Zidong;Wang, Hao;Wu, Teng;Tao, Tianyou;Mao, Jianxiao
    • Wind and Structures
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    • v.25 no.2
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    • pp.195-214
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    • 2017
  • Full-scale wind characteristics based on the field measurements is an essential element in structural wind engineering. Statistical analysis of the wind characteristics at Sutong Cable-stayed Bridge (SCB) site is conducted in this study with the recorded long-term wind data from structural health monitoring system (SHMS) between 2008 and 2015. Both the mean and turbulent wind characteristics and power spectra are comprehensively investigated and compared with those in the current codes of practice, such as the measured wind rose diagram, monthly maximum mean wind speed, turbulence intensity, integral length scale. Measurement results based on the monitoring data show that winds surrounding the SCB site are substantially influenced by the southeast monsoon in summer and strong northern wind in winter. The measured turbulence intensity is slightly higher than the recommended values in specifications, while the measured ratio of lateral to longitudinal turbulence intensity is slightly lower. An approximately linear relationship between the measured turbulence intensities and gust factors is obtained. The mean value of the turbulence integral length scale is smaller than that of typical typhoon events. In addition, it is found that the Kaimal spectrum is suitable to be adopted as the power spectrum for longitudinal wind component at the SCB site. This contribution would provide important wind characteristic references for the wind performance evaluation of SCB and other civil infrastructures in adjacent regions.

Robust Key Agreement From Received Signal Strength in Stationary Wireless Networks

  • Zhang, Aiqing;Ye, Xinrong;Chen, Jianxin;Zhou, Liang;Lin, Xiaodong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.5
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    • pp.2375-2393
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    • 2016
  • Key agreement is paramount in secure wireless communications. A promising approach to address key agreement schemes is to extract secure keys from channel characteristics. However, because channels lack randomness, it is difficult for wireless networks with stationary communicating terminals to generate robust keys. In this paper, we propose a Robust Secure Key Agreement (RSKA) scheme from Received Signal Strength (RSS) in stationary wireless networks. In order to mitigate the asymmetry in RSS measurements for communicating parties, the sender and receiver normalize RSS measurements and quantize them into q-bit sequences. They then reshape bit sequences into new l-bit sequences. These bit sequences work as key sources. Rather than extracting the key from the key sources directly, the sender randomly generates a bit sequence as a key and hides it in a promise. This is created from a polynomial constructed on the sender's key source and key. The receiver recovers the key by reconstructing a polynomial from its key source and the promise. Our analysis shows that the shared key generated by our proposed RSKA scheme has features of high randomness and a high bit rate compared to traditional RSS-based key agreement schemes.

Code development and preliminary validation for lead-cooled fast reactor thermal-hydraulic transient behavior

  • Chenglong Wang;Chen Wang;Wenxi Tian;Guanghui Su;Suizheng Qiu
    • Nuclear Engineering and Technology
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    • v.56 no.6
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    • pp.2332-2342
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    • 2024
  • Lead-cooled fast reactors (LFRs) have a wide range of application scenarios, which require the thermal-hydraulic characteristics of LFRs to be reliable. In the present paper, the Lead-cooled fast reactor Thermal-Hydraulic Analysis Code LETHAC was developed, including the models of pipe, heat exchanger, and pool. To verify the correctness of LETHAC, two experimental facilities and three experimental cases were selected, including GFT and PLOFA tests for NACIE-UP and Test-1 for CIRCE. The calculated results show the same and consistent trend with the experimental data, but there are some discrepancies. It can be found that LETHAC is suitable and reliable in predicting the transient behavior of lead-cooled system.

Features Extraction and Mechanism Analysis of Partial Discharge Development under Protrusion Defect

  • Dong, Yu-Lin;Tang, Ju;Zeng, Fu-Ping;Liu, Min
    • Journal of Electrical Engineering and Technology
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    • v.10 no.1
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    • pp.344-354
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    • 2015
  • In order to study the development of partial discharge (PD) under typical protrusion defects in gas-insulated switchgear, we applied step voltages on the defect and obtained the ${\varphi}-u$ and ${\varphi}-n$ spectrograms of ultra-high frequency (UHF) PD signals in various PD stages. Furthermore, we extracted seven kinds of features to characterize the degree of deterioration of insulation and analyzed their values, variation trends, and change rates. These characteristics were inconsistent with the development of PD. Hence, the differences of these features could describe the severity of PD. In addition, these characteristics could provide integrated characteristics regarding PD development and improve the reliability of PD severity assessment because these characteristics were extracted from different angles. To explain the variation laws of these seven kinds of parameters, we analyzed the relevant physical mechanism by considering the microphysical process of PD formation and development as well as the distortion effect generated by the space charges on the initial field. The relevant physical mechanism effectively allocated PD severity among these features for assessment, and the effectiveness and reliability of using these features to assess PD severity were proved by testing a large number of PD samples.