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Effect of the vortical structures on the hydrodynamic performance of a pitching hydrofoil

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Journal of Hydrodynamics 2024年第2期36卷 406-420页

作者： Rui Yuan Hui-yun Hao Qin Wu Yun-qing Liu biao huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

The objective is to study the vortical structural behaviors of a transient pitching hydrofoil and their effects on the hydrodynamic performance. The pitching motion of the hydrofoil is set to pitch up with an almost constant rate from 5° to 15° and then back to 5°, with the Reynolds number 4.4×10^(5) and the frequency 2 Hz. The results show that the main coherent structures around the pitching hydrofoil include small-scale laminar separation bubble (LSB), large-scale second vortex (SV) and trailing edge vortex (TEV) which are all vortical. The relationship between the vortical structure and the lift is investigated with the finite-domain impulse theory. It indicates that the major part of the lift is contributed by the LSB, whereas the shedding and the formation of the SV and TEV cause the fluctuation of the lift. The proper orthogonal decomposition (POD) method is applied to capture the most energetic modes, revealing that the LSB mode occupies a large amount of energy in the flow field. The dynamic mode decomposition (DMD) method accurately extracts the dominant frequency and modal characteristics, with the first mode corresponding to the mean flow, the second mode corresponding to the LSB structure and the third and fourth modes corresponding to the vortex shedding.

关键词： Hydrodynamics vortical structures finite-domain impulse theory proper orthogonal decomposition(POD) dynamic mode decomposition(DMD) Pitching hydrofoil

Reinforcement Learning in Process Industries:Review and Perspective

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 283-300页

作者： Oguzhan Dogru Junyao Xie Om Prakash Ranjith Chiplunkar Jansen Soesanto Hongtian Chen Kirubakaran Velswamy Fadi Ibrahim biao huang Department of Chemical and Materials Engineering University of AlbertaEdmontonT6G 1H9Canada IEEE

This survey paper provides a review and perspective on intermediate and advanced reinforcement learning(RL)techniques in process industries. It offers a holistic approach by covering all levels of the process control hierarchy. The survey paper presents a comprehensive overview of RL algorithms,including fundamental concepts like Markov decision processes and different approaches to RL, such as value-based, policy-based, and actor-critic methods, while also discussing the relationship between classical control and RL. It further reviews the wide-ranging applications of RL in process industries, such as soft sensors, low-level control, high-level control, distributed process control, fault detection and fault tolerant control, optimization,planning, scheduling, and supply chain. The survey paper discusses the limitations and advantages, trends and new applications, and opportunities and future prospects for RL in process industries. Moreover, it highlights the need for a holistic approach in complex systems due to the growing importance of digitalization in the process industries.

关键词： Process control process systems engineering reinforcement learning

Investigating the relationship between intracranial atherosclerotic plaque remodelling and diabetes using high-resolution vessel wall imaging

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World Journal of Diabetes 2024年第1期15卷 72-80页

作者： Yong-Qian Mo Hai-Yu Luo Han-Wen Zhang Yu-Feng Liu Kan Deng Xiao-Lei Liu biao huang Fan Lin Department of Radiology Peking University Shenzhen HospitalShenzhen 518000Guangdong ProvinceChina Department of Ultrasound Peking University Shenzhen HospitalShenzhen 518000Guangdong ProvinceChina The Second School of Clinical Medicine Southern Medical UniversityGuangzhou 510282Guangdong ProvinceChina Department of Radiology The First Affiliated Hospital of Shenzhen UniversityHealth Science CenterShenzhen Second People’s HospitalShenzhen 518036Guangdong ProvinceChina Research Department Philips HealthcareGuangzhou 518000Guangdong ProvinceChina Department of Radiology Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou 510000Guangdong ProvinceChina

BACKGROUND Intracranial atherosclerosis,a leading cause of stroke,involves arterial plaque formation.This study explores the link between plaque remodelling patterns and diabetes using high-resolution vessel wall imaging(HR-VWI).AIM To investigate the factors of intracranial atherosclerotic remodelling patterns and the relationship between intracranial atherosclerotic remodelling and diabetes mellitus using HR-VWI.METHODS Ninety-four patients diagnosed with middle cerebral artery or basilar artery INTRODUCTION Intracranial atherosclerotic disease is one of the main causes of ischaemic stroke in the world,accounting for approx-imately 10%of transient ischaemic attacks and 30%-50%of ischaemic strokes[1].It is the most common factor among Asian people[2].The adaptive changes in the structure and function of blood vessels that can adapt to changes in the internal and external environment are called vascular remodelling,which is a common and important pathological mechanism in atherosclerotic diseases,and the remodelling mode of atherosclerotic plaques is closely related to the occurrence of stroke.Positive remodelling(PR)is an outwards compensatory remodelling where the arterial wall grows outwards in an attempt to maintain a constant lumen diameter.For a long time,it was believed that the degree of stenosis can accurately reflect the risk of ischaemic stroke[3-5].Previous studies have revealed that lesions without significant luminal stenosis can also lead to acute events[6,7],as summarized in a recent meta-analysis study in which approximately 50%of acute/subacute ischaemic events were due to this type of lesion[6].Research[8,9]has pointed out that the PR of plaques is more dangerous and more likely to cause acute ischaemic stroke.Previous studies[10-13]have found that there are specific vascular remodelling phenomena in the coronary and carotid arteries of diabetic patients.However,due to the deep location and small lumen of intracranial arteries and limitations of imaging techniques,the relationship between intra

关键词： High-resolution vessel wall imaging Intracranial atherosclerosis Vascular remodelling Magnetic resonance imaging

Imaging-guided precision oncotherapy mediated by nanoprobes: From seeing to curing

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Chinese Chemical Letters 2024年第1期35卷 116-128页

作者： Jie Zheng Shi-Hui Chen biao huang Mingxi Zhang Quan Yuan Ran Cui College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Hubei Jiangxia Laboratory Wuhan 430200China

Malignant tumors are the main diseases threatening human life. Using precise theranostics to diagnose and cure tumors has emerged as a new method to improve patient survival. Based on the current development of precise tumor imaging, image-guided tumor therapy has received widespread attention because it is beneficial for developing precise treatment of tumors, has the potential to improve the efficacy of tumor therapy and reduce the incidence of adverse side effects. Nanoprobes, which are nanomaterial functionalized with specific biomolecules, have intrigued intense interest due to their great potential in monitoring biorecognition and biodetection evens. Benefiting from the unique advantages of nanomaterials, including the easy surface functionalization, the unique imaging performances, and the high drug loading capacity, nanoprobes have become a powerful tool to simultaneously realize tumor precise imaging, diagnosis, and therapy. This review introduces the non-invasive tumor precise imaging and highlights the recent advances of image-guided oncotherapy mediated by nanoprobes in anti-tumor drug delivery, tumor precise surgical navigation, chemodynamic therapy, and phototherapy. Finally, a perspective on the challenge and future direction of nanoprobes in imaging-guided tumor theranostics is also discussed.

关键词： Precise theranostics Imaging-guided Tumor surgical navigation Chemodynamic therapy Phototherapy Nanoprobes

Topological invariants for anomalous Floquet higher-order topological insulators

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Frontiers of physics 2023年第1期18卷 47-62页

作者： biao huang Kavli Institute for Theoretical Sciences University of Chinese Academy of SciencesBeijing 100190China

We review the recent development in constructing higher-order topological band insulators under strong periodic drivings.In particular,we focus on various approaches in formulating the anomalous Floquet topological in... 详细信息

关键词： topological Floquet higher-order

Clinical value of serum pepsinogen in the diagnosis and treatment of gastric diseases

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World Journal of Gastrointestinal Oncology 2023年第7期15卷 1174-1181页

作者： Yuan Qin Jia-Xin Geng biao huang College of Life Sciences and Medicine Zhejiang Sci-Tech UniversityHangzhou 310018Zhejiang ProvinceChina

Pepsinogen,secreted from the gastric mucosa,is the precursor of pepsin.It is categorized as pepsinogen 1 and pepsinogen 2 based on its immunogenicity.The pepsinogen content that can enter the blood circulation through the capillaries of the gastric mucosa is approximately 1%and remains stable all the time.The pepsinogen content in serum will change with the pathological changes of gastric mucosa.Therefore,the level of pepsinogen in serum can play a role in serologic biopsy to reflect the function and morphology of different regions of gastric mucosa and serve as an indicator of gastric disease.This study conducts relevant research on serum pepsinogen 1,pepsinogen 2,and the ratio of pepsinogen 1 to pepsinogen 2,and reviews their important value in clinical diagnosis of Helicobacter pylori infection,gastric ulcer,and even gastric carcinoma,providing ideas for other researchers.

关键词： Pepsinogen 1 Pepsinogen 2 Gastric diseases Serological marker Serological biopsy

Numerical study of geyser events in rainstorm systems at different scales

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Water Science and Engineering 2023年第4期16卷 381-389页

作者： Shuang-qing Zhang Jia-chun Liu biao huang Jian Zhang The National Key Laboratory of Water Disaster Prevention Hohai UniversityNanjing 210098China School of Civil and Environmental Engineering Ningbo UniversityNingbo 315211China

Considering that we still do not fully understand the behavior of air pockets trapped in rainstorm systems and water flow changes inside pipes,the study of actual geysers presents many challenges.In this study,three-dimensional numerical models were developed to investigate the mechanisms of geyser events triggered by rapid filling flows at different scales.The results showed that,in the first stage of the water–air mixture of the prototype model,a large amount of air was released quickly,and the subsequent overflow lasted for a more extended period.The transport capacity of the downstream pipe,as a critical factor,significantly influenced the water–air interaction of the geyser.Restricting the outlet area and increasing the outlet pressure simultaneously resulted in a stronger geyser.The equivalent density of the water–air mixture increased as the scale decreased during the geyser event.

关键词： Equivalent density Prototype model Storm geyser Transport capacity Water-air mixture

Experimental investigation of unsteady attached cavitating flow induced pressure fluctuation

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Journal of Hydrodynamics 2022年第1期34卷 31-42页

作者： Hou-sheng Zhang Guang-hao Chen Qin Wu biao huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China AVIC Jincheng Nanjing Engineering Institute of Aircraft System Nanjing211106China

This paper experimentally investigates the pressure fluctuation induced by the unsteady attached cavitating flow, with special focus on the quasi-periodic cloud cavitation. A simultaneous sampling method is adopted for the synchronous measurement of the wall pressure signals and the cavitating flow images in a convergent-divergent channel. The results show that the pressure fluctuation is composed of three parts, the flow noise, the low-frequency fluctuation, and the cavity collapse induced impulse, and the pressure evolution of the quasi-periodic cloud cavitation is well consistent with the cavitation evolution. The statistical analysis of the pressure fluctuation shows that, when σ > 1.01, the probability density function (PDF) is nearly in the normal distribution, implying the randomness of the pressure fluctuation, when 0.84 1.01, when σ < 0.84, the PDF becomes narrow and asymmetric. In addition, the variance and the average value of the pressure indicate that the fluctuation intensity increases downstream along the cavity and reaches the maximum at the cavity closure and it also increases with the decrease of the cavitation number. The spectral analysis shows that the low-frequency pressure fluctuations mainly consist of two dominant components, the cavity shedding induced fluctuation and the lock-in fluctuation. The cavity shedding induced frequency decreases with the decrease of the cavitation number but the lock-in frequency is kept nearly constant. According to the spectral analysis of the cavity area fluctuation and the modal analysis of the flow system, the lock-in is possibly caused when the fluctuation frequency of the cavity volume approaches the natural frequency of the flow system.

关键词： Cavitation pressure fluctuation statistical features lock-in phenomenon

Relation Extraction Based on Prompt Information and Feature Reuse

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Data Intelligence 2023年第3期5卷 824-840页

作者： Ping Feng Xin Zhang Jian Zhao Yingying Wang biao huang Jilin University Changchun Jilin 130012China Changchun Universiy Changchun Jilin 130022China Jilin Provincial Key Laboratory of Human Health State Identification and Function Enhancement Changchun Jjilin 130022China

To alleviate the problem of under-utilization features of sentence-level relation extraction,which leads to insufficient performance of the pre-trained language model and underutilization of the feature vector,a sentence-level relation extraction method based on adding prompt information and feature reuse is proposed.At first,in addition to the pair of nominals and sentence information,a piece of prompt information is added,and the overall feature information consists of sentence information,entity pair information,and prompt information,and then the features are encoded by the pre-trained language model ROBERTA.Moreover,in the pre-trained language model,BIGRU is also introduced in the composition of the neural network to extract information,and the feature information is passed through the neural network to form several sets of feature vectors.After that,these feature vectors are reused in different combinations to form multiple outputs,and the outputs are aggregated using ensemble-learning soft voting to perform relation classification.In addition to this,the sum of cross-entropy,KL divergence,and negative log-likelihood loss is used as the final loss function in this paper.In the comparison experiments,the model based on adding prompt information and feature reuse achieved higher results of the SemEval-2010 task 8 relational dataset.

关键词： relation extraction language model prompt information feature reuse loss function