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DOA estimation of high-dimensional signals based on Krylov subspace and weighted l_(1)-norm

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Journal of Systems Engineering and Electronics 2024年第3期35卷 532-540,F0002页

作者： YANG Zeqi liu Yiheng ZHANG Hua MA Shuai chang Kai liu Ning LYU Xiaode Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China National Key Laboratory of Microwave Imaging Technology Beijing 100190China School of Electronic Electrical and Communication Engineering University of Chinese Academy of SciencesBeijing 100049China Northern Institute of Electronic Equipment Beijing 100191China

With the extensive application of large-scale array antennas,the increasing number of array elements leads to the increasing dimension of received signals,making it difficult to meet the real-time requirement of direction of arrival(DOA)estimation due to the computational complexity of *** subspace algorithms require estimation of the covariance matrix,which has high computational complexity and is prone to producing spurious *** order to reduce the computational complexity of DOA estimation algorithms and improve their estimation accuracy under large array elements,this paper proposes a DOA estimation method based on Krylov subspace and weighted l_(1)-*** method uses the multistage Wiener filter(MSWF)iteration to solve the basis of the Krylov subspace as an estimate of the signal subspace,further uses the measurement matrix to reduce the dimensionality of the signal subspace observation,constructs a weighted matrix,and combines the sparse reconstruction to establish a convex optimization function based on the residual sum of squares and weighted l_(1)-norm to solve the target *** results show that the proposed method has high resolution under large array conditions,effectively suppresses spurious peaks,reduces computational complexity,and has good robustness for low signal to noise ratio(SNR)environment.

关键词： direction of arrival(DOA) compressed sensing(CS) Krylov subspace l_(1)-norm dimensionality reduction

A Novel Clutter Suppression Algorithm for Low-Slow-Small Targets Detecting Based on Sparse Adaptive Filtering

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Journal of Beijing Institute of Technology 2024年第1期33卷 54-64页

作者： Zeqi Yang Shuai Ma Ning liu Kai chang Xiaode Lyu Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China National Key Laboratory of Microwave Imaging Technology Beijing 100190China School of Electronic Electrical and Communication Engineering University of Chinese Academy of SciencesBeijing 100049China Northern Institute of Electronic Equipment Beijing 100083China

Passive detection of low-slow-small(LSS)targets is easily interfered by direct signal and multipath clutter,and the traditional clutter suppression method has the contradiction between step size and convergence *** this paper,a frequency domain clutter suppression algorithm based on sparse adaptive filtering is *** pulse compression operation between the error signal and the input reference signal is added to the cost function as a sparsity constraint,and the criterion for filter weight updating is improved to obtain a purer echo *** the same time,the step size and penalty factor are brought into the adaptive iteration process,and the input data is used to drive the adaptive changes of parameters such as step *** proposed algorithm has a small amount of calculation,which improves the robustness to parameters such as step size,reduces the weight error of the filter and has a good clutter suppression performance.

关键词： passive radar interference suppression sparse representation adaptive filtering

Three‑dimensional numerical simulation of dynamic strength and failure mode of a rock mass with cross joints

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International Journal of Coal Science & Technology 2024年第2期11卷 35-52页

作者： Tingting liu Wenxu Huang chang Xiang Qian Dong Xinping Li Chao Zhang Hubei Key Laboratory of Blasting Engineering Jianghan UniversityWuhan 430056China School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan 430070China Hainan Institute Wuhan University of TechnologySanya 572025China

To study the dynamic mechanical properties and failure characteristics of intersecting jointed rock masses with different joint distributions under confining pressure,considering the cross angleαand joint persistence ratioη,a numerical model of the biaxial Hopkinson bar test system was established using the finite element method–discrete-element model coupling *** validity of the model was verified by comparing and analyzing it in conjunction with laboratory test ***-static combined impact tests were conducted on specimens under various conditions to investigate the strength characteristics and patterns of crack initiation and *** study revealed the predominant factors influencing intersecting joints with different angles and penetrations under impact *** results show that the peak stress of the specimens decreases first and then increases with the increase of the cross ***α<60°,regardless of the value ofη,the dynamic stress of the specimens is controlled by the main ***α≥60°,the peak stress borne by the specimens decreases with increasingη.Whenα<60°,the initiation and propagation of cracks in the cross-jointed specimens are mainly controlled by the main joint,and the final failure surface of the specimens is composed of the main joint and wing ***α≥60°orη≥0.67,the secondary joint guides the expansion of the wing cracks,and multiple failure surfaces composed of main and secondary joints,wing cracks,and co-planar cracks are *** lateral confinement significantly increases the dynamic peak stress able to be borne by the *** triaxial conditions,the degree of failure of the intersecting jointed specimens is much lower than that under uniaxial and biaxial conditions.

关键词： Cross joints Joint distribution form Dynamic failure characteristics FEM–DEM BHPB

Using MsfNet to Predict the ISUP Grade of Renal Clear Cell Carcinoma in Digital Pathology Images

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Computers, Materials & Continua 2024年第1期78卷 393-410页

作者： Kun Yang Shilong chang Yucheng Wang Minghui Wang Jiahui Yang Shuang liu Kun liu Linyan Xue College of Quality and Technical Supervision Hebei UniversityBaoding071002China National and Local Joint Engineering Research Center of Metrology Instrument and System Hebei UniversityBaoding071002China Hebei Technology Innovation Center for Lightweight of New Energy Vehicle Power System Hebei UniversityBaoding071002China

Clear cell renal cell carcinoma(ccRCC)represents the most frequent form of renal cell carcinoma(RCC),and accurate International Society of Urological Pathology(ISUP)grading is crucial for prognosis and treatment *** study presents a new deep network called Multi-scale Fusion Network(MsfNet),which aims to enhance the automatic ISUP grade of ccRCC with digital histopathology pathology *** MsfNet overcomes the limitations of traditional ResNet50 by multi-scale information fusion and dynamic allocation of channel *** model was trained and tested using 90 Hematoxylin and Eosin(H&E)stained whole slide images(WSIs),which were all cropped into 320×320-pixel patches at 40×*** achieved a micro-averaged area under the curve(AUC)of 0.9807,a macro-averaged AUC of 0.9778 on the test *** Gradient-weighted Class Activation Mapping(Grad-CAM)visually demonstrated MsfNet’s ability to distinguish and highlight abnormal areas more effectively than *** t-Distributed Stochastic Neighbor Embedding(t-SNE)plot indicates our model can efficiently extract critical features from images,reducing the impact of noise and redundant *** results suggest that MsfNet offers an accurate ISUP grade of ccRCC in digital images,emphasizing the potential of AI-assisted histopathological systems in clinical practice.

关键词： Renal cell carcinoma computer-aided diagnosis pathology image deep learning machine learning

Comparative Assessment of Impacts of Future Climate change on Runoff in Upper Daqinghe Basin,China

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Chinese Geographical Science 2024年第3期34卷 564-578页

作者： INGABIRE Romaine chang Yuru liu Xia CAO Bo UMUGWANEZA Adeline SHEN Yanjun Key Laboratory of Agricultural Water Resources Hebei-Key Laboratory of Water Saving AgricultureCenter for Agricultural Re-sources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050022China Uni-versity of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Desert and Oasis Ecology Xinjiang Insti-tute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China

Assessing runoff changes is of great importance especially its responses to the projected future climate change on local scale basins because such analyses are generally done on global and regional scales which may lead to generalized conclusions rather than specific *** change affected the runoff variation in the past in the upper Daqinghe Basin,however,the climate was mainly considered uncertain and still needs further studies,especially its future impacts on runoff for better water resources management and *** with a set of climate simulations,a daily conceptual hydrological model(MIKE11-NAM)was applied to assess the impact of climate change on runoff conditions in the Daomaguan,Fuping and Zijingguan basins in the upper Daqinghe *** hydrological data(2008–2017)were used to evaluate the applicability of the MIKE11-NAM *** bias correction,future projected climate change and its impacts on runoff(2025–2054)were analysed and compared to the baseline period(1985–2014)under three shared social economic pathways(SSP1-2.6,SSP2-4.5,and SSP5-8.5)scenarios from Coupled Model Intercomparison Project Phase 6(CMIP6)*** MIKE-11 NAM model was applicable in all three Basins,with both R^(2)and Nash-Sutcliffe Efficiency coefficients greater than 0.6 at daily scale for both calibration(2009–2011)and validation(2012–2017)periods,*** uncertainties remain,temperature and precipitation are projected to increase compared to the baseline where higher increases in precipitation and temperature are projected to occur under SSP2-4.5 and SSP5-8.5 scenarios,respectively in all the *** changes will range between 12%–19%whereas temperature change will be 2.0℃–2.5℃ under the SSP2-4.5 and SSP5-8.5 scenarios,*** addition,higher warming is projected to occur in colder months than in warmer ***,the runoff of these three basins is projected to respond to projected climate changes differe

关键词： runoff climate change MIKE11-NAM model Coupled Model Intercomparison Project Phase 6(CMIP6) upper Daqinghe Basin,China

Cholecystokinin and cholecystokinin-A receptor: An attractive treatment strategy for biliary dyskinesia?

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World Journal of Gastroenterology 2024年第3期30卷 283-285页

作者： Jun chang Yan liu Ting-Can Jiang Lan Zhao Jian-Wei liu Tianjin Institute of Acupuncture and Moxibustion The First Teaching Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300381China Department of Gastroenterology Tianjin Hospital of Integrated Traditional Chinese and Western Medicine Nankai HospitalTianjin 300100China State Key Laboratory of Component-Based Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China School of Integrative Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China

Biliary dyskinesia is a relatively common gastrointestinal disease that is increas-ing in incidence as living standards ***,its underlying pathogenesis remains unclear,hindering the development of therapeutic ***,“Expression and functional study of cholecystokinin-A receptors on the interstitial Cajal-like cells of the guinea pig common bile duct”demonstrated that cholecystokinin(CCK)regulates the contractile function of the common bile duct through interaction with the CCK-A receptor in interstitial Cajal-like cells,contributing to improving the academic understanding of biliary tract dynamics and providing emerging directions for the pathogenesis and clinical management of biliary *** letter provides a brief overview of the role of CCK and CCK-A receptors in biliary dyskinesia from the perspective of animal experiments and clinical studies,and discusses prospects and challenges for the clinical application of CCK and CCK-A receptors as potential therapeutic targets.

关键词： Cholecystokinin Cholecystokinin-A receptor Biliary dyskinesia Interstitial Cajal-like cell Therapeutic target

Refining the targeted population and achieving better for colorectal cancer screening

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World Journal of Gastroenterology 2024年第25期30卷 3140-3142页

作者： Nuo-Ya Zhou Yi-Xiu Lin liu-Xiang Chen lian-Song Ye Bing Hu Department of Gastroenterology and Hepatology/Medical Engineering Integration Laboratory of Digestive Endoscopy West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

This editorial comments on the article entitled“Stage at diagnosis of colorectal cancer through diagnostic route:Who should be screened?”by Agatsuma et al,who conducted a retrospective study aiming at clarifying the stage at colorectal cancer(CRC)diagnosis based on different diagnostic *** share our opinion about CRC screening *** current situation suggests the need for a more specific and targeted population for CRC screening.

关键词： Colorectal cancer Screening Early diagnosis Technology Cost-effectiveness

Advances in the studies of the supported ruthenium catalysts for CO_(2)methanation

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Chinese Journal of Catalysis 2024年第8期63卷 1-15页

作者： Chenyang Shen Menghui liu Song He Haibo Zhao chang-jun liu Collaborative Innovation Center of Chemical Science&Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China Key Laboratory of Mesoscopic Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023JiangsuChina State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan430074HubeiChina

CO_(2)methanation has a potential in the large-scale utilization of carbon *** has also been considered to be useful for the renewable energy *** commercial pipeline for natural gas transportation can be directly applied for the methane product of CO_(2)*** supported ruthenium(Ru)catalyst has been confirmed to be active and stable for CO_(2)methanation with its high ability in the dissociation of hydrogen and the strong binding of carbon ***_(2)methanation over the supported Ru catalyst is structure *** size of the Ru catalyst and the support have significant effects on the activity and the mechanism.A significant challenge re-mained is the structural controllable preparation of the supported Ru catalyst toward a sufficiently high low-temperature *** this review,the recent progresses in the investigations of the supported Ru catalysts for CO_(2)methanation are *** challenges and the future devel-opments are also discussed.

关键词： Ruthenium Carbon dioxide Methanation Hydrogenation Catalyst and metal-support interaction

Single-Cell Mapping of Brain Myeloid Cell Subsets Reveals Key Transcriptomic changes Favoring Neuroplasticity after Ischemic Stroke

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Neuroscience Bulletin 2024年第1期40卷 65-78页

作者： Fangxi liu Xi Cheng Chuansheng Zhao Xiaoqian Zhang chang liu Shanshan Zhong Zhouyang liu Xinyu Lin Wei Qiu Xiuchun Zhang Department of Neurology.The First Affiliated Hospital of China Medical University Shenyang 110001China Department of Neurology The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510630China Stroke Center The First Affiliated Hospital of China Medical UniversityShenyang 110001China

Interactions between brain-resident and periph-eral infiltrated immune cells are thought to contribute to neuroplasticity after cerebral ***,con-ventional bulk sequencing makes it challenging to depict this complex immune *** single-cell RNA sequencing,we mapped compositional and transcriptional features of peri-infarct immune *** were the predominant cell type in the peri-infarct region,displaying a more diverse activation pattern than the typical pro-and anti-inflammatory state,with axon tract-associated micro-glia(ATMs)being associated with neuronal *** inference suggested that infiltrated monocyte-derived macrophages(MDMs)exhibited a gradual fate trajectory transition to activated ***-cellular crosstalk between MDMs and microglia orchestrated anti-inflammatory and repair-promoting microglia phenotypes and promoted post-stroke neurogenesis,with SOX2 and related Akt/CREB signaling as the underlying *** description of the brain's immune landscape and its relationship with neurogenesis provides new insight into promoting neural repair by regulating neuroinflammatory responses.

关键词： Ischemic stroke Monocyte-derived macrophage Microglia Neurogenesis Single-cell sequencing