80 research outputs found
Development of a Fatigue Life Assessment Model for Pairing Fatigue Damage Prognoses with Bridge Management Systems
Fatigue damage is one of the primary safety concerns for steel bridges reaching the end of their design life. Currently, US federal requirements mandate regular inspection of steel bridges for fatigue cracks; however, these inspections rely on visual inspection, which is subjective to the inspectorâs physically inherent limitations. Structural health monitoring (SHM) can be implemented on bridges to collect data between inspection intervals and gather supplementary information on the bridgesâ response to loads. Combining SHM with finite element analyses, this paper integrates two analysis methods to assess fatigue damage in the crack initiation and crack propagation periods of fatigue life. The crack initiation period is evaluated using S-N curves, a process that is currently used by the FHWA and AASHTO to assess fatigue damage. The crack propagation period is evaluated with linear elastic fracture mechanic-based finite element models, which have been widely used to predict steady-state crack growth behavior. Ultimately, the presented approach will determine the fatigue damage prognoses of steel bridge elements and damage prognoses are integrated with current condition state classifications used in bridge management systems. A case study is presented to demonstrate how this approach can be used to assess fatigue damage on an existing steel bridge
Pressure drop characteristics of adjustable slotted distributor in fluidized bed
[EN] In this paper, a fluidized bed with a adjustable slotted gas distributor was used to study fluidization in a 230 mmĂ200 mm rectangular fluidized bed by adjusting the spacing between the two slotted gas distributors. The pressure drop of the distributor at different inlet gas velocities was obtained and the change law between pressure drop and distance between distributors was summarized. This study provides a theoretical basis for the application of adjustable slotted gas distributor fluidized bed.The authors acknowledge Projects supported by the National Natural Science Foundation of China (Grant No. 31571906 & No.21506163).Tong, Z.; Chaoran, L.; Qing, X.; Zhanyong, L.; W., J. (2018). Pressure drop characteristics of adjustable slotted distributor in fluidized bed. En IDS 2018. 21st International Drying Symposium Proceedings. Editorial Universitat Politècnica de València. 1751-1758. https://doi.org/10.4995/IDS2018.2018.7729OCS1751175
Medical image segmentation based on self-supervised hybrid fusion network
Automatic segmentation of medical images has been a hot research topic in the field of deep learning in recent years, and achieving accurate segmentation of medical images is conducive to breakthroughs in disease diagnosis, monitoring, and treatment. In medicine, MRI imaging technology is often used to image brain tumors, and further judgment of the tumor area needs to be combined with expert analysis. If the diagnosis can be carried out by computer-aided methods, the efficiency and accuracy will be effectively improved. Therefore, this paper completes the task of brain tumor segmentation by building a self-supervised deep learning network. Specifically, it designs a multi-modal encoder-decoder network based on the extension of the residual network. Aiming at the problem of multi-modal feature extraction, the network introduces a multi-modal hybrid fusion module to fully extract the unique features of each modality and reduce the complexity of the whole framework. In addition, to better learn multi-modal complementary features and improve the robustness of the model, a pretext task to complete the masked area is set, to realize the self-supervised learning of the network. Thus, it can effectively improve the encoderâs ability to extract multi-modal features and enhance the noise immunity. Experimental results present that our method is superior to the compared methods on the tested datasets
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A CpG Methylation Signature as a Potential Marker for Early Diagnosis of Hepatocellular Carcinoma From HBV-Related Liver Disease Using Multiplex Bisulfite Sequencing.
BACKGROUND: Aberrant methylation of CpG sites served as an epigenetic marker for building diagnostic, prognostic, and recurrence models for hepatocellular carcinoma (HCC). METHODS: Using Illumina 450K and EPIC Beadchip, we identified 34 CpG sites in peripheral blood mononuclear cell (PBMC) DNA that were differentially methylated in early HCC versus HBV-related liver diseases (HBVLD). We employed multiplex bisulfite sequencing (MBS) based on next-generation sequencing (NGS) to measure methylation of 34 CpG sites in PBMC DNA from 654 patients that were divided into a training set (n = 442) and a test set (n = 212). Using the training set, we selected and built a six-CpG-scorer (namely, cg14171514, cg07721852, cg05166871, cg18087306, cg05213896, and cg18772205), applying least absolute shrinkage and selection operator (LASSO) regression. We performed multivariable analyses of four candidate risk predictors (namely, six-CpG-scorer, age, sex, and AFP level), using 20 times imputation of missing data, non-linearly transformed, and backwards feature selection with logistic regression. The final model's regression coefficients were calculated according to "Rubin's Rules". The diagnostic accuracy of the model was internally validated with a 10,000 bootstrap validation dataset and then applied to the test set for validation. RESULTS: The area under the receiver operating characteristic curve (AUROC) of the model was 0.81 (95% CI, 0.77-0.85) and it showed good calibration and decision curve analysis. Using enhanced bootstrap validation, adjusted C-statistics and adjusted Brier score were 0.809 and 0.199, respectively. The model also showed an AUROC value of 0.84 (95% CI 0.79-0.88) of diagnosis for early HCC in the test set. CONCLUSIONS: Our model based on the six-CpG-scorer was a reliable diagnosis tool for early HCC from HBVLD. The usage of the MBS method can realize large-scale detection of CpG sites in clinical diagnosis of early HCC and benefit the majority of patients
Ultra-Low-Frequency Radio Astronomy Observations from a Selenocentric Orbit: first results of the Longjiang-2 experiment
This paper introduces the first results of observations with the
Ultra-Long-Wavelength (ULW) -- Low Frequency Interferometer and Spectrometer
(LFIS) on board the selenocentric satellite Longjiang-2. We present a brief
description of the satellite and focus on the LFIS payload. The in-orbit
commissioning confirmed a reliable operational status of the instrumentation.
We also present results of a transition observation, which offers unique
measurements on several novel aspects. We estimate the RFI suppression required
for such a radio astronomy instrumentation at the Moon distances from Earth to
be of the order of 80 dB. We analyse a method of separating Earth- and
satellite-originated radio frequency interference (RFI). It is found that the
RFI level at frequencies lower than a few MHz is smaller than the receiver
noise floor.Comment: Accepted for publication in Experimental Astronomy; 22 pages, 11
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The Connection between Buddhist Temples, the Landscape, and Monarchical Power: A Comparison between Tuoba Hong (471–499) from the Northern Wei Dynasty and Li Shimin (626–649) from the Tang Dynasty
Since the Western Jin period, Buddhism has confronted bureaucratic power within the architectural landscape. In this study, historical records and archaeological reports of two Buddhist temples—the Siyuan Temple 思遠佛寺 built during the reign of Tuoba Hong 拓跋宏 and Emperor Xiaowen 孝文帝 of the Northern Wei dynasty, and the Zhaoren Temple 昭仁寺, built during the reign of Li Shimin 李世民 and Emperor Taizong 唐太宗 of the Tang dynasty—were examined. A comparison was made of the two temples’ geographic locations in relation to cities while considering period-specific phenomena. This study also considers mountains, water, and topographical features. The geographic information reflects differences in the ideas of the ruling class and monarchs of the two historical periods. The findings are that both Buddhist temples were close to the capital and both emperors demonstrated the supremacy of their power by building them. Therefore, the religious landscape owes its formation, development, and underlying significance to emperors and social groups
The Connection between Buddhist Temples, the Landscape, and Monarchical Power: A Comparison between Tuoba Hong (471â499) from the Northern Wei Dynasty and Li Shimin (626â649) from the Tang Dynasty
Since the Western Jin period, Buddhism has confronted bureaucratic power within the architectural landscape. In this study, historical records and archaeological reports of two Buddhist templesâthe Siyuan Temple ćé ä˝ĺŻş built during the reign of Tuoba Hong ćčˇĺŽ and Emperor Xiaowen ĺćĺ¸ of the Northern Wei dynasty, and the Zhaoren Temple ćäťĺŻş, built during the reign of Li Shimin ćä¸ć° and Emperor Taizong ĺĺ¤ŞĺŽ of the Tang dynastyâwere examined. A comparison was made of the two templesâ geographic locations in relation to cities while considering period-specific phenomena. This study also considers mountains, water, and topographical features. The geographic information reflects differences in the ideas of the ruling class and monarchs of the two historical periods. The findings are that both Buddhist temples were close to the capital and both emperors demonstrated the supremacy of their power by building them. Therefore, the religious landscape owes its formation, development, and underlying significance to emperors and social groups
âSustainableâ Recording and Preservation of Zangniang Stupa and Sangzhou Lamasery in Qinghai, China with Heritage Building Information Model
This paper research and discusses the âsustainableâ workflow and heritage recording method of historic building information modelling (HBIM) for Chinese Tibetan architecture and pagodas and explains the vital role of recording heritage information to protect cultural relics. Considering the Tibetan Buddhist Pagoda in Yushu, Qinghai, China, this paper explores the collaborative modelling mechanism and ideas between heritage surveying and scanning information and software, and the problems of these two methods. Through research, we have obtained successful cases of HBIM based on field scanning and mapping, online software collaborative modelling (Rhino, Bentley, Autodesk Computer-Aided Design), sustainable management, and display. It is an information model constructed according to construction logic and accurate information and one that realises sustainable and full-cycle recording functions by continuous recording, updating, and iterating. This method removes a limitation of HBIM in that it considers one-time information construction and delivery mode but does not consider and explore sustainable recording work. It will significantly promote more records on the heritage information of Tibetan architecture. The results will also directly serve the protection of architectural heritage in Qinghai Province, China and the âSilk Road (South Asia Section) Transnational Serial Application for World Heritageâ work
Evaluation of the PEG Density in the PEGylated Chitosan Nanoparticles as a Drug Carrier for Curcumin and Mitoxantrone
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