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Journal of Advanced Ceramics 2024年第5期13卷 590-601页

作者： Hui Chen Yulei Zhang Yanqin Fu wenhan gai Junhao Zhao Haohui Zhang Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials Northwestern Polytechnical UniversityXi’an 710072China Henan Key Laboratory of High Performance Carbon Fiber Reinforced Composites Institute of Carbon Matrix CompositesHenan Academy of SciencesZhengzhou 450046China

Ultra-high-temperature ceramic nanowires have shown increasing potential for use as thermal structural ***,novel single-crystal Hf_(0.5)Ta_(0.5)C solid solution nanowires were synthesized and incorporated with a HfC coating to construct a robust structure with Hf_(0.5)Ta_(0.5)C solid solution nanowires uniformly distributed and interconnected within the *** novel Hf_(0.5)Ta_(0.5)C solid solution nanowires could effectively hinder crack propagation through crack tip pinning and crack *** mechanism substantially enhanced the elastic modulus and fracture toughness of the HfC coating by 53.29%and 59.67%,*** toughened HfC coating displayed superior fracture toughness and good interfacial binding strength with the substrate to resist severe oxidation and ***,the high thermal conductivity of the toughened HfC coating promoted heat ***,in comparison to the pure HfC coating,the toughened HfC coating displayed smaller mass and linear ablation rates of−0.35 mg·s^(−1)and−0.46μm·s^(−1),which decreased by 39.66%and 36.98%,*** work not only simultaneously enhances the mechanical properties and ablation resistance of HfC-coated carbon/carbon(C/C)composites but also provides novel prospects for advanced ultrahigh-temperature ceramic nanowires under extreme conditions.

关键词： Hf_(x)Ta_(1−x)C solid solution nanowires HfC coating carbon/carbon(C/C)composites mechanical performance ablationresistance

Sublayer design and ablation resistance of CVD-TaC alternate coatings with different crystallite morphologies for C/C composites

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Journal of Materials Science & Technology 2023年第10期141卷 1-10页

作者： Jing’an Kong Yulei Zhang Hanhui Wang Guohui Chen wenhan gai Pengfei Zhang Hejun Li State Key Laboratory of Solidification Processing Carbon/Carbon Composites Research CenterNorthwestern Polytechnical UniversityXi’anShanxi 710072China

Tantalum carbon(TaC)alternate coatings with sublayers comprised of different crystallite morphologies were prepared on carbon/carbon composites by chemical vapor *** ablative behaviors and defending mechanisms were both *** specimen with the sublayer composed of columnar crystals exhibited a better ablation resistance due to the toughness enhancement induced by the lami-nated ***,the mechanical denudation of the sample only containing acicular crystals and the coating spallation caused by superfluous gaseous products of the sample with the sublayer composed of nanocrystals both indicate their inferior anti-ablation *** is believed that the results will be helpful for the structural design and practical application of chemical vapor deposition(CVD)alternate coatings.

关键词： Alternate coating Chemical vapor deposition Crystallite morphology Carbon/carbon composite Ablation behavior

Hydrogen sulfide reduces oxidative stress in Huntington's disease via Nrf2

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Neural Regeneration Research 2025年第6期20卷 1776-1788页

作者： Zige Jiang Dexiang Liu Tingting Li Chengcheng gai Danqing Xin Yijing Zhao Yan Song Yahong Cheng Tong Li Zhen Wang Department of Physiology School of Basic Medical SciencesCheeloo College of MedicineShandong UniversityJinanShandong ProvinceChina Department of Medical Psychology and Ethics School of Basic Medicine SciencesCheeloo College of MedicineShandong UniversityJinanShandong ProvinceChina Department of Neurosurgery Surgery Qingdao Municipal HospitalQingdaoShandong ProvinceChina

The pathophysiology of Huntington's disease involves high levels of the neurotoxin quinolinic acid. Quinolinic acid accumulation results in oxidative stress, which leads to neurotoxicity. However, the molecular and cellular mechanisms by which quinolinic acid contributes to Huntington's disease pathology remain unknown. In this study, we established in vitro and in vivo models of Huntington's disease by administering quinolinic acid to the PC12 neuronal cell line and the striatum of mice, respectively. We observed a decrease in the levels of hydrogen sulfide in both PC12 cells and mouse serum, which was accompanied by down-regulation of cystathionine β-synthase, an enzyme responsible for hydrogen sulfide production. However, treatment with NaHS(a hydrogen sulfide donor) increased hydrogen sulfide levels in the neurons and in mouse serum, as well as cystathionine β-synthase expression in the neurons and the mouse striatum, while also improving oxidative imbalance and mitochondrial dysfunction in PC12 cells and the mouse striatum. These beneficial effects correlated with upregulation of nuclear factor erythroid 2-related factor 2 expression. Finally, treatment with the nuclear factor erythroid 2-related factor 2inhibitor ML385 reversed the beneficial impact of exogenous hydrogen sulfide on quinolinic acid-induced oxidative stress. Taken together, our findings show that hydrogen sulfide reduces oxidative stress in Huntington's disease by activating nuclear factor erythroid 2-related factor 2,suggesting that hydrogen sulfide is a novel neuroprotective drug candidate for treating patients with Huntington's disease.

关键词： apoptosis cystathionine-β-synthase nuclear factor erythroid 2-related factor 2 Huntington's disease hydrogen sulfide mitochondrion neuroplasticity oxidative stress quinolinic acid reactive oxygen species

A Fully Soft Bionic Grasping Device with the Properties of Segmental Bending Shape and Automatically Adjusting Grasping Range

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Journal of Bionic Engineering 2022年第5期19卷 1334-1348页

作者： Lingjie gai Xiaofeng Zong School of Automation China University of GeosciencesWuhan 430074China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan 430074China Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of EducationWuhan 430074China

In this paper,we propose a fully Soft Bionic Grasping Device(SBGD),which has advantages in automatically adjusting the grasping range,variable stiffness,and controllable bending *** device consists of soft gripper structures and a soft bionic bracket *** adopt the local thin-walled design in the soft gripper *** design improves the grippers’bending efficiency,and imitate human finger’s segmental bending *** addition,this work also proposes a pneumatic soft bionic bracket structure,which not only can fix grippers,but also can automatically adjust the grasping space by imitating the human adjacent fingers’opening and closing *** to the above advantages,the SBGD can grasp larger or smaller objects than the regular grasping ***,to grasp small objects reliably,we further present a new Pinching Grasping(PG)*** great performance of the fully SBGD is verified by *** work will promote innovative development of the soft bionic grasping robots,and greatly meet the applications of dexterous grasping multi-size and multi-shape objects.

关键词： Fully soft bionic grasping device Local thin-walled grippers Soft bionic bracket Adjust grasping range automatically Segmental bending shape New pinching grasping method

A modular four-modal soft grasping device

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Science China(Technological Sciences) 2022年第8期65卷 1845-1858页

作者： gai LingJie ZONG XiaoFeng School of Automation China University of GeosciencesWuhan 430074China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan 430074China Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of EducationWuhan 430074China

It is a key challenge for soft grasping devices to stably grasp unstructured objects with multi-size and multi-shape. The conventional single-function grippers have some limitations in grasping the above kinds of objects. This work proposes a modular four-modal soft grasping device(MFSGD), which consists of soft fingers, suction cups, soft wrapper, and other structures. It can perform a variety of grasping modes such as bending grasping mode, wrapping grasping mode, end liftingsucking mode, and side fixed-sucking mode. It may be one of the devices with the most grasping modes at present. Moreover, the device adopts a fully modular design with different structures connected by magnets. It is not only convenient to disassemble or assemble, so as to solve the mutual interference of different modal structures problem during grasping, but also simplifies the fabrication of the multi-modal grasping device. In addition, this work matches the suitable grasping modes for objects of different shapes and sizes, and obtains the relative characteristics of the MFSGD. The proposed device can improve the ability of the grasping robots, and is expected to play an important role in economic and industrial fields.

关键词： four-modal soft grasping device modular suction cups soft wrapper soft fingers

Closed-loop dynamic control allocation for aircraft with multiple actuators

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Chinese Journal of Aeronautics 2013年第3期26卷 676-686页

作者： gai Wendong Wang Honglun Science and Technology on Aircraft Control Laboratory Beihang University

A closed-loop control allocation method is proposed for a class of aircraft with multiple actuators. Nonlinear dynamic inversion is used to design the baseline attitude controller and derive the desired moment increment. And a feedback loop for the moment increment produced by the deflections of actuators is added to the angular rate loop, then the error between the desired and actual moment increment is the input of the dynamic control allocation. Subsequently, the stability of the closed-loop dynamic control allocation system is analyzed in detail. Especially, the closedloop system stability is also analyzed in the presence of two types of actuator failures： loss of effectiveness and lock-in-place actuator failures, where a fault detection subsystem to identify the actuator failures is absent. Finally, the proposed method is applied to a canard rotor/wing （CRW） aircraft model in fixed-wing mode, which has multiple actuators for flight control. The nonlinear simulation demonstrates that this method can guarantee the stability and tracking performance whether the actuators are healthy or fail.

关键词： Canard rotor/wing aircraft Closed-loop control allocation Dynamic inversion Flight control systems Redundant actuators

A modified simulated annealing algorithm and an excessive area model for floorplanning using fixed-outline constraints

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Frontiers of Information Technology & Electronic Engineering 2016年第11期17卷 1228-1244页

作者： De-xuan ZOU gai-ge WANG gai PAN Hong-wei QI School of Electrical Engineering and Automation Jiangsu Normal University School of Computer Science and Technology Jiangsu Normal University

Outline-free floorplanning focuses on area and wirelength reductions, which are usually meaningless, since they can hardly satisfy modern design requirements. We concentrate on a more difficult and useful issue, fixed-outline floorplanning. This issue imposes fixed-outline constraints on the outline-free floorplanning, making the physical design more interesting and challenging. The contributions of this paper are primarily twofold. First, a modified simulated annealing(MSA) algorithm is proposed. In the beginning of the evolutionary process, a new attenuation formula is used to decrease the temperature slowly, to enhance MSA's global searching capacity. After a period of time, the traditional attenuation formula is employed to decrease the temperature rapidly, to maintain MSA's local searching capacity. Second, an excessive area model is designed to guide MSA to find feasible solutions readily. This can save much time for refining feasible solutions. Additionally, B*-tree representation is known as a very useful method for characterizing floorplanning. Therefore, it is employed to perform a perturbing operation for MSA. Finally, six groups of benchmark instances with different dead spaces and aspect ratios—circuits n10, n30, n50, n100, n200, and n300—are chosen to demonstrate the efficiency of our proposed method on fixed-outline floorplanning. Compared to several existing methods, the proposed method is more efficient in obtaining desirable objective function values associated with the chip area, wirelength, and fixed-outline constraints.

关键词： Fixed-outline floorplanning Modified simulated annealing algorithm Global search Excessive area model B*-tree representation

Chinese Question-Answering System

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Journal of Computer Science & Technology 2004年第4期19卷 479-488页

作者： gai-TaiHuang Hsiu-HsenYao InstituteofStrategicDefenseManagement.＂NationalDefeT~se＂ManagementCollege NDUP.O.BOX90046-8Chung-HoTaipei DepartmentofComputerEngineering YuanZeUniversity135Yuan-TungRoadChungliTaoyuan

Traditional Chinese text retrieval systems return a ranked list of documentsin response to a user''s request. While a ranked list of documents may be an appropriate response forthe user, frequently it is not. Usually it would be better for the system to provide the answeritself instead of requiring the user to search for the answer in a set of documents. Since Chinesetext retrieval has just been developed lately, and due to various specific characteristics ofChinese language, the approaches to its retrieval are quite different from those studies andresearches proposed to deal with Western language. Thus, an architecture that augments existingsearch engines is developed to support Chinese natural language question answering. In this paper anew approach to building Chinese question-answering system is described, which is thegeneral-purpose, fully-automated Chinese quest ion-answering system available on the web. In theapproach, we attempt to represent Chinese text by its characteristics, and try to convert theChinese text into ERE (E: entity, R: relation) relation data lists, and then to answer the questionthrough ERE relation model. The system performs quite well giving the simplicity of the techniquesbeing utilized. Experimental results show that question-answering accuracy can be greatly improvedby analyzing more and more matching ERE relation data lists. Simple ERE relation data extractiontechniques work well in our system making it efficient to use with many backend retrieval engines.

关键词： ERE relation model conceptual schema question-answering informationretrieval

Evolution and Governance of the Structure of Marine Economic Networks in China’s Coastal Areas: Based on Sea-related A-share Listed Companies

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Chinese Geographical Science 2024年第5期34卷 899-916页

作者： LI Bo CAO gai Key Research Base of Humanities and Social Sciences of Ministry of Education Institute of Marine Sustainable DevelopmentLiaoning Normal UniversityDalian 116029China School of Maritime Economics and Management Dalian Maritime UniversityDalian 116026China

Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic ***,as the focus of urban research shifts from internal static attributes to external dynamic linkages,the importance of marine economic net-work research is beginning to *** construction of the marine economic network in China’s coastal areas is necessary to change the flow of land and sea resources and optimize regional marine economic *** data from headquarters and branches of sea-related A-share listed enterprises to construct the marine economic network in China,we use social network analysis(SNA)to discuss the characteristics of its evolution as of 2010,2015,and 2020 and its *** following results were obtained.1)In terms of topological characteristics,the scale of the marine economic network in China’s coastal areas has accelerated and expan-ded,and the connections have become increasingly close;thus,this development has complex network characteristics.2)In terms of spatial structure,the intensity of the connection fluctuates and does not form stable development support;the group structure gradually becomes clear,but the overall pattern is fragmented;there are spatial differences in marine economic agglomeration radiation;the radi-ation effect of the eastern marine economic circle is obvious;and the polarization effect of northern and southern marine economic circles is *** this basis,we construct a framework for the governance of a marine economic network with the market,the government,and industry as the three governing *** clarifying the driving factors and building objectives of marine economic network construction,this study aims to foster the high-quality development of China’s marine economy.

关键词： marine economic network sea-related A-share listed companies social network analysis(SNA) network governance China’s coastal areas

Analytical and Experimental Study on Complex Compressed Air Pipe Network

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Chinese Journal of Mechanical Engineering 2015年第5期28卷 1023-1029页

作者： gai Yushou CAI Maolin SHI Yan School of Automation Science and Electrical Engineering Beihang University

To analyze the working characteristics of complex compressed air networks, numerical methods are widely used which are based on finite element technology or intelligent algorithms. However, the effectiveness of the numerical methods is limited. In this paper, to provide a new method to optimize the design and the air supply strategy of the complex compressed air pipe network, firstly, a novel method to analyze the topology structure of the compressed air flow in the pipe network is initially proposed. A matrix is used to describe the topology structure of the compressed air flow. Moreover, based on the analysis of the pressure loss of the pipe network, the relationship between the pressure and the flow of the compressed air is derived, and a prediction method of pressure fluctuation and air flow in a segment in a complex pipe network is proposed. Finally, to inspect the effectiveness of the method, an experiment with a complex network is designed. The pressure and the flow of airflow in the network are measured and studied. The results of the study show that, the predicted results with the proposed method have a good consistency with the experimental results, and that verifies the air flow prediction method of the complex pipe network. This research proposes a new method to analyze the compressed air network and a prediction method of pressure fluctuation and air flow in a segment, which can predicate the fluctuation of the pressure according to the flow of compressed air, and predicate the fluctuation of the flow according to the pressure in a segment of a complex pipe network.

关键词： compressed air pipeline network topology structure flow prediction topology