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Vibration suppression for rotating space slender flexible structures based on novel deformation description and NNSMC controller with hyperbolic tangent function

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Chinese Journal of Aeronautics 2024年第10期37卷 339-364页

作者： Dongyang shang Xiaopeng LI Men YIN Sainan ZHOU School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China

Rotating Space Slender Flexible Structures(RSSFS)are extensively utilized in space operations because of their light weight,mobility,and low energy *** realize the accurate space operation of the RSSFS,it is necessary to establish a precise mechanical model and develop a control algorithm with high ***,with the application of traditional control strategies,the RSSFS often suffers from the chattering phenomenon,which will aggravate structure *** this paper,novel deformation description is put forward to balance modeling accuracy and computational efficiency of the RSSFS,which is better appropriate for real-time ***,the Neural Network Sliding Mode Control(NNSMC)strategy modified by the hyperbolic tangent(tanh)function is put forward to compensate for modeling errors and reduce the chattering phenomenon,thereby improving the trajectory tracking accuracy of the ***,a mathematical model for the RSSFS is developed according to the novel deformation description and the vibration theory of flexible *** of the deformation accuracy between different models proves that the novel modeling method proposed has high modeling ***,the universal approximation property of the Radial Basis Function(RBF)neural network is put forward to determine and compensate for modeling errors,which consist of higher-order modes and the uncertainties of external *** addition,the tanh function is proposed as the reaching law in the conventional NNSMC strategy to suppress driving torque *** control law of modified NNSMC strategy and the adaptive law of weight coefficients are developed according to the Lyapunov theorem to guarantee the RSSFS ***,the simulation and physical experimental tests of the RSSFS with different control strategies are *** results show that the control law according to the novel deformation description and the modified NNSMC strategy can obta

关键词： Space slender flexible structure Novel deformation description RBF neural network Vibration suppression Hyperbolic tangent function

Babao Dan Inhibits Gastric Cancer Progression in vivo Through Multiple Signaling Pathways

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World Journal of Traditional Chinese Medicine 2024年第1期10卷 14-21页

作者： Hai-Xia shang Yi Fang Bin Guan Jian-Hua Guan Jun Peng jin-Yan Zhao Jiu-Mao Lin Institute of Oncology of Academy of Integrative Medicine Fujian University of Traditional Chinese MedicineFuzhouFujianChina Key Laboratory of Integrative Medicine of Fujian Province University Fujian University of Traditional Chinese MedicineFuzhouFujianChina Fujian Key Laboratory of Integrative Medicine on Geriatric Fujian University of Traditional Chinese MedicineFuzhouFujianChina Innovation and Transformation Center Fujian University of Traditional Chinese MedicineFuzhouFujianChina Xiamen Traditional Chinese Medicine Co. Ltd.XiamenFujianChina

Objective:The aim of this study was to explore the effects of Babao dan(BBD),a traditional Chinese medicine,on gastric cancer(GC)progression in *** and Methods:A subcutaneous xenograft mouse model of GC was established using MGC80-3 *** terminal deoxynucleotidyl transferase-mediated dUTP:2'-deoxyuridine 5'-triphosphate-biotin nick-end labeling method was adopted to detect cell apoptosis in *** expression levels of proteins associated with proliferation,apoptosis,and angiogenesis were measured by immunohistochemical staining or western blotting(WB).The activation and protein levels of p-c-Jun N-terminal kinase(JNK),p-p38,p-extracellular-regulated kinase 1/2,p-nuclear factor-κB(NF-κB),and p-STAT3 were examined by Bio-plex and ***:BBD significantly inhibited tumor growth in GC mouse models with no adverse effect on body weight or organ *** was also found that BBD significantly suppressed the proliferation of GC tumor cells,induced the apoptosis of tumor cells,and inhibited angiogenesis through inactivating with mitogen-activated protein kinase,NF-κB,and STAT3 ***:BBD exerts suppressive effects on GC tumor growth by regulating multiple pathways in vivo,which may provide a novel treatment option for GC therapy.

关键词： Babao dan gastric cancer multiple signaling pathways proliferation traditional Chinese medicine

Energy-Function Based Pilot Protection Scheme for Hybrid UHVDC Transmission Applying Improved Hausdorff Distance

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 891-902页

作者： Zijiang Wang Youping Fan Ben shang Yinbiao Shu School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China Institute of Next Generation Power Systems&International Standards Wuhan UniversityWuhan 430072China CSEE IEEE

A hybrid UHVDC transmission system applying LCC as the rectifier and MMC as the inverter combines the advantages of both converter types,which makes this protection scheme more complicated.A new pilot protection scheme for a three-terminal hybrid DC transmission system applying energy functions is *** energy function for LCC is applied to MMC to derive the energy level of the hybrid ***,an improved Hausdorff distance(IHD)algorithm is proposed to detect the difference in energy levels between the normal and fault *** abrupt change in energy level is characterized by IHD change *** points at which the IHD change rate exceeds the threshold at converter stations are applied to determine the fault line and to estimate the fault *** proposed protection scheme is then verified by a simulation model of the Wudongde±800 kV three-terminal hybrid UHVDC transmission *** appropriate sampling frequency is selected for a real-time calculation,and the threshold is selected considering the effect of *** show the proposed scheme can identify and trip fault lines quickly and effectively,even for a 600Ωgrounding *** waveshape similarity algorithms are compared and *** with existing protection schemes,the proposed scheme transmits less data to improve communication speed and reliability.

关键词： Energy function Hausdorff distance pilot protection UHVDC transmission

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哈尔滨市可持续发展的趋势分析

地域研究与开发 2007年第1期26卷 31-34页

作者：周嘉谢远云尚金城哈尔滨师范大学生命与环境科学学院地理系东北师范大学环境科学研究所长春130024

可持续发展评判的指标体系是对可持续发展进行科学评判和决策的一个重要组成部分。从经济、社会、人口、资源、环境5个方面构建了由35个指标构成的哈尔滨市的可持续发展指标体系，并对其1995-2004年的可持续发展趋势进行了分析。分析结... 详细信息

可持续发展评判的指标体系是对可持续发展进行科学评判和决策的一个重要组成部分。从经济、社会、人口、资源、环境5个方面构建了由35个指标构成的哈尔滨市的可持续发展指标体系，并对其1995-2004年的可持续发展趋势进行了分析。分析结果表明，哈尔滨市从1995-2004年经济发展一直呈现稳步上升的趋势，社会、人口、环境和资源子系统呈现比较波动的趋势。2000年后，遂渐进入环境质量提高、资源消耗量下降的时期，环境污染、资源消耗与发展的综合指数越采越低．发展趋势也渐好。说明哈尔滨市的可持续发展的能力在不断提高。

关键词：可持续发展指标体系趋势分析哈尔滨市

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区域环境规划的价值观和自然观

东北师大学报（自然科学版） 2000年第3期32卷 89-93页

作者：曹勇宏尚金城中国科学院长春地理研究所吉林长春130021 东北师范大学环境科学系吉林长春130024

论述了区域环境规划所应树立的正确的价值观和自然观 ,其中包括环境伦理观、资源价值观、新发展观、系统生态观和全球观 .并阐明在此影响下的环境规划能协调人与自然的关系 ,促进人类社会的可持续发展 .

关键词：区域环境规划价值观自然观环境伦理观

Plant-derived nanovesicles as an emerging platform for cancer therapy

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Acta Pharmaceutica Sinica B 2024年第1期14卷 133-154页

作者： Hanzhe Liu Guo-Feng Luo Zhengjun shang The State Key Laboratory Breeding Base of Basic Science of Stomatology(Hubei-MOST)&Key Laboratory of Oral Biomedicine Ministry of Education School and Hospital of StomatologyWuhan UniversityWuhan 430079China

Plant-derived nanovesicles(PDNVs)derived from natural green products have emerged as an attractive nanoplatform in biomedical *** are usually characterized by unique structural and biological functions,such as the bioactive lipids/proteins/nucleic acids as therapeutics and targeting groups,immune-modulation,and long-term *** the rapid development of nanotechnology,materials,and synthetic chemistry,PDNVs can be engineered with multiple functions for efficient drug delivery and specific killing of diseased cells,which represent an innovative biomaterial with high biocompatibility for fighting against *** this review,we provide an overview of the state-of-theart studies concerning the development of PDNVs for cancer *** original sources,methods for obtaining PDNVs,composition and structure are introduced *** an emphasis on the featured application,the inherent anticancer properties of PDNVs as well as the strategies in constructing multifunctional PDNVs-based nanomaterials will be discussed in ***,some scientific issues and technical challenges of PDNVs as promising options in improving anticancer therapy will be discussed,which are expected to promote the further development of PDNVs in clinical translation.

关键词： Naturally occurring nanovesicles Plant Nanotechnology Drug delivery Cancer therapy

Enhancing Deep Learning Semantics:The Diffusion Sampling and Label-Driven Co-Attention Approach

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Computers, Materials & Continua 2024年第5期79卷 1939-1956页

作者： ChunhuaWang Wenqian shang Tong Yi Haibin Zhu State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China School of Computer and Cyber Sciences Communication University of ChinaBeijing100024China School of Computer Science and Engineering Guangxi Normal UniversityGuilin541004China Department of Computer Science Nipissing UniversityNorth BayON P1B 8L7Canada

The advent of self-attention mechanisms within Transformer models has significantly propelled the advancement of deep learning algorithms,yielding outstanding achievements across diverse ***,self-attention mechanisms falter when applied to datasets with intricate semantic content and extensive dependency *** response,this paper introduces a Diffusion Sampling and Label-Driven Co-attention Neural Network(DSLD),which adopts a diffusion sampling method to capture more comprehensive semantic information of the ***,themodel leverages the joint correlation information of labels and data to introduce the computation of text representation,correcting semantic representationbiases in thedata,andincreasing the accuracyof semantic ***,the model computes the corresponding classification results by synthesizing these rich data semantic *** on seven benchmark datasets show that our proposed model achieves competitive results compared to state-of-the-art methods.

关键词： Semantic representation sampling attention label-driven co-attention attention mechanisms

Carbonation of Pure Minerals in Portland Cement:Evolution in Products as a Function of Water-to-solid Ratio

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1214-1222页

作者： XIONG Kun shang Xiaopeng LI Hongyan WANG Dan Zhengzhou Lutong Highway Construction Co. Ltd.Zhengzhou 450052China (Special Glass Key Lab of Hainan Province)&(State Key Laboratory of Marine Resource Utilization in South China Sea) Hainan UniversityHaikou 570228China Department of Architectural Engineering Shandong Urban Construction Vocational CollegeJinan 250103China (State Key Laboratory of High Performance Civil Engineering Materials Jiangsu Sobute New Materials Co.Ltd.)&(School of Material Science and EngineeringSoutheast UniversityNanjing 211189China)

Minerals in Portland cement including tricalcium silicate(C_(3)S),β-dicalcium silicate(β-C_(2)S),tricalcium aluminate(C_(3)A),and tetracalcium ferroaluminate(C_(4)AF),show a significantly different activity and product evolution for CO_(2)curing at various water-to-solid *** pure minerals were synthesized and subject to CO_(2)curing in this study to make an in-depth understanding for the carbonation properties of cement-based *** showed that the optimum water-to-solid ratios of C_(3)S,β-C_(2)S,C_(3)A and C_(4)AF were 0.25,0.15,0.30 and 0.40 for carbonation,corresponding to 2 h carbonation degree of 38.5%,38.5%,24.2%,and 21.9%,*** produced calcite duringβ-C_(2)S carbonation decreased as the water-to-solid ratio increased,with an increase in content of metastable CaCO_(3)of vaterite and *** thermodynamic stability of CaCO_(3)produced during carbonation was C_(3)A>C_(4)AF>β-C_(2)S>C_(3)*** carbonation degree of Portland cement was predicted based on the results of pure minerals and the composition of cement,and the error of predicted production of CaCO_(3)was only 1.1%,which provides a potential method to predict carbonation properties of systems with a complex mineral composition.

关键词： accelerated carbonation portland cement calcium carbonate water-to-solid ratio

Debris Flow Susceptibility Evaluation in Meizoseismal Region:A Case Study in Jiuzhaigou,China

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Journal of Earth Science 2024年第1期35卷 263-279页

作者： Yongwei Li Linrong Xu Yonghui shang Shuyang Chen School of Civil Engineering Central South UniversityChangsha 410075China National Engineering Research Center of High-Speed Railway Construction Technology Central South UniversityChangsha 410075China School of Civil Engineering Central South University of Forestry and TechnologyChangsha 410004China

Jiuzhaigou is situated on a mountain-canyon region and is famous for frequent tectonic *** abundance of loose co-seismic landslides and collapses were produced on gullies after the Jiuzhaigou Earthquake on August 8,2017,which was served as material source for debris flow in later *** flow appears frequently which are seriously endangering the safety of people's lives and *** the earliest debris flow appeared in areas where no case ever reported *** debris flow susceptibility evaluation(DFSE)is used for predicting the areas prone to debris flow,which is urgently required to avoid hazards and help to guide the strategy of preventive ***,this work employs debris flow in Jiuzhaigou to reveal the characteristics of disaster-pregnant environment and to explore the application of machine learning in *** new viewpoints are suggested:(i)Material density factor of debris flow is first adopted in this work,and it is proved to be a critical factor for triggering debris flows by sensitivity analysis method.(ii)Deep neural network and convolutional neural network(CNN)achieve relatively good area under the curve(AUC)values and are 0.021-0.024 higher than traditional machine learning methods.(iii)Watershed units combined with CNNbased model can achieve more accurate,reliable and practical susceptibility *** work provides an idea for prevention of debris flow in mountainous lands.

关键词： machine learning earthquakes debris flow susceptibility convolutional neural network deep neural network watershed unit