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Reorientation and obstacle avoidance control of free-floating modular robots using sinusoidal oscillator

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Chinese Journal of Aeronautics 2024年第6期37卷 262-275页

作者： Zhiyuan YANG Mingzhu LAI Jian qi Ning zhao Xin SUI Jie zhao Yanhe ZHU State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China School of Mathematics and Statistics Hainan Normal UniversityHaikou 571158China

This paper presents that a serpentine curve-based controller can solve locomotion control problems for articulated space robots with extensive flight phases,such as obstacle avoidance during free floating or attitude adjustment before *** proposed algorithm achieves articulated robots to use closed paths in the joint space to accomplish the above *** snakes,which can shuttle through gaps and adjust their landing posture by swinging their body during gliding in jungle environments,inspired the design of two *** first maneuver generates a rotation of the system by varying the moment of inertia between the joints of the robot,with the magnitude of the net rotation depending on the controller *** maneuver can be repeated to allow the robot to reach arbitrary *** second maneuver involves periodic undulations,allowing the robot to avoid collisions when the trajectory of the global Center of Mass(CM)passes through the *** maneuvers are based on the improved serpenoid curve,which can adapt to redundant systems consisting of different numbers of ***,the simulation illustrates that combining the two maneuvers can help a free-floating chain-type robot traverse complex *** proposed algorithm can be used with similar articulated robot models.

关键词： Collision avoidance Modularrobots Reorientation Free-floating space robots Nonholonomic systems Biologically inspired controllers Serpenoid curve

Sound event localization and detection based on deep learning

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Journal of Systems Engineering and Electronics 2024年第2期35卷 294-301页

作者： zhao Dada DING Kai qi Xiaogang CHEN Yu FENG Hailin School of Mathematics and Statistics Xidian UniversityXi’an 710071China Science and Technology on Near-Surface Detection Laboratory Wuxi 214035China

Acoustic source localization(ASL)and sound event detection(SED)are two widely pursued independent research *** recent years,in order to achieve a more complete spatial and temporal representation of sound field,sound event localization and detection(SELD)has become a very active research *** paper presents a deep learning-based multioverlapping sound event localization and detection algorithm in three-dimensional ***-Mel spectrum and generalized cross-correlation spectrum are joined together in channel dimension as input *** features are classified and regressed in parallel after training by a neural network to obtain sound recognition and localization results *** channel attention mechanism is also introduced in the network to selectively enhance the features containing essential information and suppress the useless ***,a thourough comparison confirms the efficiency and effectiveness of the proposed SELD *** experiments show that the proposed algorithm is robust to reverberation and environment and can achieve higher recognition and localization accuracy compared with the baseline method.

关键词： sound event localization and detection(SELD) deep learning convolutional recursive neural network(CRNN) channel attention mechanism

Visible Light Indoor Positioning System Based on Pisarenko Harmonic Decomposition and Neural Network

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Chinese Journal of Electronics 2024年第1期33卷 195-203页

作者： Li zhao Yi REN qi WANG Lange DENG Feng ZHANG School of Electronic Information Engineering Xi’an Technological University

Visible-light indoor positioning is a new generation of positioning technology that can be integrated into smart lighting and optical communications. The current received signal strength(RSS)-based visible-light positioning systems struggle to overcome the interferences of background and indoor-reflected noise. Meanwhile, when ensuring the lighting, it is impossible to use the superposition of each light source to accurately distinguish light source information; furthermore, it is difficult to achieve accurate positioning in complex indoor environments. This study proposes an indoor positioning method based on a combination of power spectral density detection and a neural network. The system integrates the mechanism for visible-light radiation detection with RSS theory, to build a back propagation neural network model fitting for multiple reflection channels. Different frequency signals are loaded to different light sources at the beacon end, and the characteristic frequency and power vectors are obtained at the location end using the Pisarenko harmonic decomposition method. Then, a complete fingerprint database is established to train the neural network model and conduct location tests. Finally, the location effectiveness of the proposed algorithm is verified via actual positioning experiments. The simulation results show that, when four groups of sinusoidal waves with different frequencies are superimposed with white noise, the maximum frequency error is 0.104 Hz and the maximum power error is 0.0362 W. For the measured positioning stage, a 0.8 m × 0.8 m × 0.8 m solid wood stereoscopic positioning model is constructed, and the average error is 4.28 cm. This study provides an effective method for separating multi-source signal energies, overcoming background noise, and improving indoor visible-light positioning accuracies.

关键词： Neural networks Measurement uncertainty Position measurement Harmonic analysis Light emitting diodes Frequency estimation Indoor positioning systems

A new technique for correction of iatrogenic upper eyelid retraction by using a composite flap of the orbicularis muscle and fascia on the anterior surface of the tarsal plate

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Chinese Journal of Plastic and Reconstructive Surgery 2024年第3期6卷 116-123页

作者： Kaichong Nie Lidan Chen Xinzhu qi Shiruo Zhang Xuanyu yin Miaomiao zhao Yuanyuan Du Shanghai EyesShine BeauCare Medical Aesthetic Clinic Shanghai201107China

Background:Upper eyelid retraction is a challenging complication of cosmetic upper eyelid *** avoid extra trauma,we developed a new technique for correcting iatrogenic upper eyelid retraction by postmigrating a compound flap of the orbicularis muscle and fascia(OFC)on the anterior surface of the tarsal *** method extends the aponeurosis of the levator palpebrae superioris muscle(LPS),which can achieve a good correction for post-blepharoplasty ***:We collected data from 15 patients with mild to moderate iatrogenic upper eyelid retraction who were treated at our hospital between February 2017 and December *** OFC was used to replace the missing part of the LPS,and post-migration of the LPS and fixation of the OFC to the tarsal margin were *** outcome measurements included postoperative binocular symmetry,double eyelid smoothness,eyelid fullness,margin reflex distance(MRD1),degree of eyelid closure,and exposure *** patients were followed-up at seven days,one month,and six months ***:One patient with moderate eyelid retraction showed undercorrection 6 months postoperatively,with the upper eyelid margin located at the upper edge of the *** remaining patients had the upper eyelid margin stabilized at 1.0–2.0 mm below the upper corneal *** observational indicators were satisfactory,including binocular symmetry,double eyelid fluency,and eyelid *** the follow-up,no exposure keratitis was *** MRD1 indexes after the operation were significantly different(P<0.001)from those before the ***:Extension and post-migration of the LPS using the orbicularis muscle and OFC structure can effectively correct mild iatrogenic eyelid retraction after ptosis with less damage and good postoperative eyelid morphology and closure function.

关键词： Upper eyelid retraction Levator palpebrae superioris Orbicularis muscle and fascia Migration

Advanced organic electrode materials for aqueous rechargeable batteries

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Science China Chemistry 2024年第1期67卷 137-164页

作者： Gaojing Yang Yaxun Zhu qi zhao Zhimeng Hao Yong Lu qing zhao Jun Chen Frontiers Science Center for New Organic Matter Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)College of ChemistryNankai UniversityTianjin 300071China

Organic electrode materials take advantages of potentially sustainable production and structural tunability compared with present commercial inorganic electrode ***,their applications in traditional rechargeable batteries with nonaqueous electrolytes suffer from the premature failure and safety *** comparison,aqueous rechargeable batteries based on organic electrode materials have received extensive attentions in recent years for low-cost and sustainable energy storage systems due to their inherent *** review aims to provide a comprehensive summary on the recent progress in advanced organic electrode materials for aqueous rechargeable *** start from the overview of working principles and general design strategies of organic electrode materials in aqueous rechargeable *** the research advances of organic electrode materials in various aqueous rechargeable batteries are highlighted in terms of charge carriers(monovalent ions,multivalent ions,and anions).We emphasized the characteristics of organic electrode materials in various charge ***,the critical challenges and future efforts of aqueous organic rechargeable batteries are *** organic electrode materials with better electronic conductivity and fast reaction kinetics are still needed to build advanced aqueous batteries for commercial applications.

关键词： organic electrode materials aqueous batteries organic batteries rechargeable batteries

Monotonic mechanical behaviour of compacted completely decomposed granite with various inclusion levels of incineration bottom ash

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第8期25卷 670-679页

作者： Han-Lin WANG Cheng-Shuang yin qian-Yi ZHANG qi-Wei LIU Zhen-Yu yin Dong-Xing XUAN Askar KHASANOV Research Center for Advanced Underground Space Technologies of Hunan University Changsha 410082China Key Laboratory of Building Safety and Energy Efficiency of the Ministry of Education Hunan UniversityChangsha 410082China College of Civil Engineering Hunan UniversityChangsha 410082China School of Civil Engineering Zhengzhou UniversityZhengzhou 450001China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Department of Applied and Theoretical Mechanics Samarkand State UniversitySamarkandUzbekistan

1 Introduction Completely decomposed granite(CDG)is widely distributed in South China(Xu et al.,2022;Wang et al.,2023).The parent granite rock mass gradually loses features during the weathering process,and thus needs to be reinforced when used(Lan et al.,2003;Dassekpo et al.,2017;Alamanis et al.,2021).On the other hand,considering the huge demand for construction materials and limited natural resources,it is increasingly important to fully utilize solid waste(Gruhler et al.,2019;Anagnostopoulos et al.,2020;Jiang et al.,2022,2023a,2023b).With high strength and environment-friendly characteristics,incineration bottom ash(IBA)seems to be a suitable reinforcement material for CDG(Ahmed and Khalid,2011;Alhassan and Tankó,2012;Toraldo et al.,2013;Lynn et al.,2017;Xuan et al.,2018;Tang et al.,2020).

关键词： incineration behaviour utilize

Unlocking high-efficiency oxygen evolution reaction through Co-N coordination engineering in Co@N-doped porous carbon core–shell nanoparticles

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Nano Research 2024年第8期17卷 7068-7076页

作者： Shucheng Liu Yu Shuai Xiaosi qi zhao Ding Yi Liu College of Big Data and Information Engineering Guizhou UniversityGuiyang 550025China College of Physics Guizhou Province Key Laboratory for Photoelectrics Technology and ApplicationGuizhou UniversityGuiyang 550025China

Modulation of metal sites coordination can significantly refine the electronic architecture of catalysts,thereby improving their catalytic *** work successfully developed a core–shell Co@N-doped porous carbon(Co@NC)catalyst by pyrolyzing the COF/MOF(IISERP-COF3/ZIF-67)composite in an inert *** Co@NC catalyst exhibited impressive oxygen evolution reaction(OER)performance,with a small overpotential of 304 mV and a modest Tafel slope of 88.6 mV·dec^(−1) in a 1 M KOH,alongside remarkable stability,maintaining 98.5%of its activity over 13 *** role of IISERP-COF3 was pivotal in preventing Co atom aggregation during the ZIF-67 pyrolysis,which facilitated the creation of mesopores for enhanced mass transport and ***,it effectively modulated the Co-N coordination to fine-tune the electronic structure,thereby optimizing the catalyst's capacity for adsorption of intermediates and boosting its intrinsic *** functional theory(DFT)studies corroborate that the exceptional OER efficiency of Co@NC can be linked to the enhanced Co-N coordination,optimizing the localized electronic structure at the Co active *** study not only proposes an innovative approach for optimizing COF/MOF as effective electrocatalysts but also clears the path for the emergence of affordable,high-performance alternatives to precious metal-based catalysts,marking a significant advancement in sustainable energy technologies.

关键词： covalent organic framework(COF) metal-organic framework(MOF) core-shell structure catalysts oxygen evolution reaction

Asperuloside Promotes Apoptosis of Cervical Cancer Cells through Endoplasmic Reticulum Stress-Mitochondrial Pathway

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Chinese Journal of Integrative Medicine 2024年第1期30卷 34-41页

作者： qi Zhi-min WANG Xia LIU Xia zhao Juan Medical Examination Center Hebei Province Hospital of Chinese MedicineShijiazhuang(050011)China Department of Gynaecology and Obstetrics Hebei Province Hospital of Chinese MedicineShijiazhuang(050011)China Experimental Center for Teaching Hebei Medical UniversityShijiazhuang(050017)China

Objective: To investigate the effects of asperuloside on cervical cancer based on endoplasmic reticulum(ER) stress and mitochondrial pathway. Methods: Different doses(12.5–800 μg/mL) of asperuloside were used to treat cervical cancer cell lines Hela and CaSki to calculate the half maximal inhibitory concentration(IC_(50)) of asperuloside. The cell proliferation was analyzed by clone formation assay. Cell apoptosis, intracellular reactive oxygen species(ROS) and mitochondrial membrane potential were determined by flow cytometry. The protein expressions of cleaved-caspase-3, Bcl-2, Bax, Cyt-c, cleaved-caspase-4 and glucose-regulated protein 78(GRP78) were analyzed by Western blot. And the inhibitor of ER stress, 4-phenyl butyric acid(4-PBA) was used to treat cervical cancer cells to further verify the role of ER stress in the apoptosis of cervical cancer cells induced by asperuloside. Results: Asperuloside of 325, 650, and 1300 μg/mL significantly inhibited the proliferation and promoted apoptosis of Hela and CaSki cells(P<0.01). All doses of asperuloside significantly increased intracellular ROS levels, reduced mitochondrial membrane potential, significantly reduced Bcl-2 protein expression level, and increased Bax, Cyt-c, GRP78 and cleaved-caspase-4 expressions(P<0.01). In addition, 10 mmol/L 4-PBA treatment significantly promoted cell proliferation and reduced apoptosis(P<0.05), and 650 μg/mL asperuloside could reverse 4-PBA-induced increased cell proliferation, decreased apoptosis and cleaved-caspase-3,-4 and GRP78 protein expressions(P<0.05). Conclusion: Our study revealed the role of asperuloside in cervical cancer, suggesting that asperuloside promotes apoptosis of cervical cancer cells through ER stress-mitochondrial pathway.

关键词： asperuloside Chinese medicine cervical cancer endoplasmic reticulum stress mitochondrial damage apoptosis

Aspirin suppresses hepatocellular carcinoma progression by inhibiting platelet activity

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2742-2756页

作者： Li-Jun zhao Zhi-yin Wang Wei-Ting Liu Li-Li Yu Hao-Nan qi Jie Ren Chen-Guang Zhang Hematology Laboratory The First Affiliated Hospital of Xinxiang Medical UniversityXinxiang 453100Henan ProvinceChina Xinxiang Key Laboratory of Tumor Microenvironment and Immunotherapy School of Medical TechnologyXinxiang Medical UniversityXinxiang 453003Henan ProvinceChina School of Public Health Xinxiang Medical UniversityXinxiang 453003Henan ProvinceChina

BACKGROUND Hepatocellular carcinoma(HCC)is the most common malignant liver disease in the ***(PLTs)are known to play a key role in the maintenance of liver homeostasis and the pathophysiological processes of a variety of liver *** is the most classic antiplatelet ***,the molecular mechanism of platelet action and whether aspirin can affect HCC progression by inhibiting platelet activity need further *** To explore the impact of the antiplatelet effect of aspirin on the development of *** Platelet-rich plasma,platelet plasma,pure platelet,and platelet lysate were prepared,and a coculture model of PLTs and HCC cells was ***-8 analysis,apoptosis analysis,Transwell analysis,and real-time polymerase chain reaction(RT-PCR)were used to analyze the effects of PLTs on the growth,metastasis,and inflammatory microenvironment of ***-PCR and Western blot were used to detect the effects of platelet activation on tumor-related signaling *** was used to block the activation and aggregation of PLTs both in vitro and in vivo,and the effect of PLTs on the progression of HCC RESULTS PLTs significantly promoted the growth,invasion,epithelial-mesenchymal transition,and formation of an inflammatory microenvironment in HCC *** PLTs promoted HCC progression by activating the mitogenactivated protein kinase/protein kinase B/signal transducer and activator of transcription three(MAPK/AKT/STAT3)signaling ***,aspirin inhibited HCC progression in vitro and in vivo by inhibiting platelet *** PLTs play an important role in the pathogenesis of HCC,and aspirin can affect HCC progression by inhibiting platelet *** results suggest that antiplatelet therapy has promising application prospects in the treatment and combined treatment of HCC.

关键词： Platelets Antiplatelet therapy Hepatocellular carcinoma Aspirin Antitumor