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Design and performance analysis of indoor calibration device for the forcemeasuring system of the tractor three-point hitch

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International Journal of Agricultural and Biological Engineering 2023年第3期16卷 47-54页

作者： Dong Dai Du Chen xu mao Yawei Zhang Yutong Li Shumao Wang Bin Zhang Department of Mechanical and Electrical Engineering College of EngineeringChina Agricultural UniversityBeijing 100083China Department of Mechanical Design and Manufacturing College of EngineeringChina Agricultural UniversityBeijing 100083China Beidahuang Agricultural Service Group Heilongjiang Agricultural Machinery Service Co. LtdHarbin 150090China

The real-time monitoring of the load in farming by the sensor installed on the tractor's three-point hitch can effectively improve the farming efficiency and force-position combined control,reduce the compaction risk of the wheel on the soil and reduce the fuel consumption in farming ***,the measurement and quantification of the loads on the three-point hitch have some problems remaining unresolved:testing the accuracy and reliability of a load measuring system is hard when the tractor works in a field,the mathematical model of spatial forces usually lacks a practical and effective validation,and the calibration process of the measurement system is inconvenient and incomplete while easily causing a low ***,this paper builds a new spatial-force mathematical model based on the geometry of a three-point *** eliminate the discrepancy of the geometric model with the actual structure and to refine the mathematical model,a calibration process is conducted by developing a calibration bench,which is equipped with a data acquisition system and a multi-parameter monitoring *** three-point hitch installed on this calibration bench is subject to steady-state *** loading force,angle of the lower drawbar,and three-component forces(three shaft pin sensors’forces)of the three-point hitch are well *** applying for the measured data to calibrate the theoretical mathematic model eventually derives the resultant force from all the three-component forces,a dynamical loading bench was developed to test the calculated resultant force for the three-point hitch during the sinusoidal and randomly variant dynamical loadings tests.A hitch force measurement system is also developed to collect real-time data and calculate the resultant force of measured three-component forces through the calibrated mathematical *** results of the dynamical loading tests show that the average relative error MRE=1.09%with an average force measurem

关键词： tractor three-point hitch hitch force calibration bench hitch force measurement system dynamic loading verification method

Lateral Flight Stability of Two Hovering Model Insects

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Journal of Bionic Engineering 2014年第3期11卷 439-448页

作者： Na xu mao Sun Ministry-of-Education Key Laboratory of Fluid Mechanics Beihang University Beijing 100191 P. R. China

The longitudinal disturbance motion of different insects at hovering flight has the same modal structure. Here, we consider the case of lateral motion. The lateral dynamic flight stability of two model insects, hoverfly and honeybee, at hovering flight is studied. The method of computational fluid dynamics is applied to compute the stability derivatives. The techniques of eigenvalue and eigenvector analysis are used to solve the equations of motion. Results show that the lateral disturbance motion of the hoverfly has three natural modes of motion： an unstable divergence mode, a stable oscillatory mode and a stable subsidence mode, and the flight is unstable; while the honeybee has a different modal structure （a stable slow subsidence mode, a stable fast subsidence mode, and a nearly neutrally stable oscillatory mode） and the flight is nearly neutrally stable. The change in modal structure between the two insects is due to their roll-moment/side-velocity derivative having different sign, and the sign difference is because that the hoverfly has a relatively small, but the honeybee has a relatively large, distance between the wing roots and the center of mass. Thus, unlike the case of longitudinal motion, for lateral motion, some insects have different modal structures and stability properties from others.

关键词： insect hovering flight dynamic flight stability modal structure

Reasonable suppression of polysulfides/polyselenides shuttle based on MXene in Na-SeS_(2)batteries

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Rare Metals 2023年第5期42卷 1594-1602页

作者： Qiu-Ju Yang Jing Zhao Wei Gao Wei Zhong Yu-Ruo Qi Jin Han Shu-Juan Bao mao-Wen xu School of Materials and Energy Southwest UniversityChongqing400715China Helmholtz Institute Ulm Ulm89081Germany Karlsruhe Institute of Technology Karlsruhe76021Germany

Metal-sulfur/selenium batteries have become the focus of new-generation energy storage systems due to the advantages of low-cost and high energy ***,it still suffers from the notorious shuttle of polysulfides/polyselenides,poor electronic conductivity and tremendous volume ***,a dual defense system for polysulfides/polyselenides was proposed and constructed based on *** nitrogen-doped porous carbon(NPC)decorated by Ti_(3)C_(2)T_(x)MXene(M@NPC)was employed as the SeS_(2)host(SeS_(2)@M@NPC).Particularly,Ti_(3)C_(2)T_(x)sheets wrapped on NPC guarantee the rapid ion diffusion and serve as the first barrier for SeS_(2)and dissolved sodium polysulfides/***,the few-layered Ti_(3)C_(2)T_(x)sheets coated on glass fiber separators act as the second barrier for alleviating the shuttle of polysulfides/polyselenides through physical interception and chemical *** this elaborate design,the integrated Na-SeS_(2)battery achieves a high specific capacity of 1243 mAh·g^(-1)at 1.0C,revealing a distinct superiority over its counterparts(SeS_(2)@M@NPC,1083mAh·g^(-1)at 0.5C;and SeS_(2)@NPC,823 mAh·g^(-1)at 0.5C).The findings gained in this work provide a creative idea for the construction of durable room-temperature Na-SeS_(2)batteries based on MXenes and their derivative materials.

关键词： MXene Integrated strategy Shuttle effect Room temperature(RT)Na-SeS_(2)batteries

A framework of force of information influence and application for C4KISR system

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Journal of Systems Engineering and Electronics 2024年第2期35卷 430-443页

作者： mao Shaojie DIAO Lianwang SUN Yu WANG Heng YI Kan xu Xin mao Xiaobin ZHANG Kecheng SHENG Long Science and Technology on Information Systems Engineering Laboratory The 28th Research Institute of China Electronics Technology Group CorporationNanjing 210007China Unit 94860 of the PLA Nanjing 210008China

The subversive nature of information war lies not only in the information itself, but also in the circulation and application of information. It has always been a challenge to quantitatively analyze the function and effect of information flow through command, control, communications, computer, kill, intelligence,surveillance, reconnaissance (C4KISR) system. In this work, we propose a framework of force of information influence and the methods for calculating the force of information influence between C4KISR nodes of sensing, intelligence processing,decision making and fire attack. Specifically, the basic concept of force of information influence between nodes in C4KISR system is formally proposed and its mathematical definition is provided. Then, based on the information entropy theory, the model of force of information influence between C4KISR system nodes is constructed. Finally, the simulation experiments have been performed under an air defense and attack scenario. The experimental results show that, with the proposed force of information influence framework, we can effectively evaluate the contribution of information circulation through different C4KISR system nodes to the corresponding tasks. Our framework of force of information influence can also serve as an effective tool for the design and dynamic reconfiguration of C4KISR system architecture.

关键词： information warfare command control communications computer kill intelligence surveillance reconnaissance(C4KISR)system information circulation force of information influence information entropy

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废旧三元锂离子电池正极材料回收技术综述

广东化工 2024年第14期51卷 85-88页

作者：饶媛媛徐懋方继明胡在京蒋阳童国庆合肥国轩电池材料有限公司安徽合肥230012 合肥工业大学材料科学与工程学院安徽合肥230009

随着三元体系锂离子电池市场份额的快速增加,废旧三元锂离子电池将迎来爆发式增长,但同时带来的环境污染和资源浪费问题也日益严重。于是系统地开发废旧三元锂离子电池材料的回收及再生技术,将有助于防治废旧电池污染、缓解镍钴锂资源... 详细信息

随着三元体系锂离子电池市场份额的快速增加,废旧三元锂离子电池将迎来爆发式增长,但同时带来的环境污染和资源浪费问题也日益严重。于是系统地开发废旧三元锂离子电池材料的回收及再生技术,将有助于防治废旧电池污染、缓解镍钴锂资源短缺压力,促进我国锂电池产业的良性发展。本文介绍近年来废旧三元锂离子电池资源化利用的研究进展,包括废旧三元电池预处理和废旧三元材料回收利用技术,其中,废旧三元正极材料资源化利用包括火法冶金、湿法冶金、分离再生等方面,分析了各工艺优势与不足,提出了目前回收废旧三元电池正极材料急需解决的难题,为未来废旧三元锂离子电池绿色环保、短流程、低成本、自动化的回收发展方向提供重要参考和思路。

关键词：三元正极材料有价金属浸取分离回收再生

Advances in immunotherapy for biliary tract cancers

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Chinese Medical Journal 2024年第5期137卷 524-532页

作者： Yuhao Zhao mao Yang Jiayi Feng xu’an Wang Yingbin Liu Department of Biliary–Pancreatic Surgery Renji Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200127China Shanghai Cancer Institute State Key Laboratory of Oncogenes and Related GenesShanghai 200127China Shanghai Key Laboratory of Biliary Tract Disease Shanghai 200082China

Biliary tract cancers(BTC),a heterogeneous disease with poor prognosis,including gallbladder cancer(GBC),intrahepatic cholangiocarcinoma(ICC),and extrahepatic cholangiocarcinoma(ECC).Although surgery is currently the primary regimen to treat BTC,most BTC patients are diagnosed at an advanced stage and miss the opportunity of surgical *** a result,non-surgical therapy serves as the main intervention for advanced *** recent years,immunotherapy has emerged as one of the most promising therapies in a number of solid cancers,and it includes immune checkpoint inhibitors(ICIs)monotherapy or combined therapy,tumor vaccines,oncolytic virus immunotherapy,adoptive cell therapy(ACT),and cytokine ***,these therapies have been practiced in limited clinical settings in patients with *** this review,we focus on the discussion of latest advances of immunotherapy in BTC and update the progress of multiple current clinical trials with different immunotherapies.

关键词： Immunotherapy Biliary tract cancers Immune checkpoint inhibitors Cholangiocarcinoma Gallbladder cancer

Strengthening Network Security: Deep Learning Models for Intrusion Detectionwith Optimized Feature Subset and Effective Imbalance Handling

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Computers, Materials & Continua 2024年第2期78卷 1995-2022页

作者： Bayi xu Lei Sun Xiuqing mao Chengwei Liu Zhiyi Ding School of Cyber Science and Engineering Zhengzhou UniversityZhengzhou450000China Three Academy Information Engineering UniversityZhengzhou450001China The 3rd Research Department Nanjing Research Institute of Electronic EngineeringNanjing210007China

In recent years,frequent network attacks have highlighted the importance of efficient detection methods for ensuring cyberspace *** paper presents a novel intrusion detection system consisting of a data prepro-cessing stage and a deep learning model for accurately identifying network *** have proposed four deep neural network models,which are constructed using architectures such as Convolutional Neural Networks(CNN),Bi-directional Long Short-Term Memory(BiLSTM),Bidirectional Gate Recurrent Unit(BiGRU),and Attention *** models have been evaluated for their detection performance on the NSL-KDD *** enhance the compatibility between the data and the models,we apply various preprocessing techniques and employ the particle swarm optimization algorithm to perform feature selection on the NSL-KDD dataset,resulting in an optimized feature ***,we address class imbalance in the dataset using focal ***,we employ the BO-TPE algorithm to optimize the hyperparameters of the four models,maximizing their detection *** test results demonstrate that the proposed model is capable of extracting the spatiotemporal features of network traffic data *** binary and multiclass experiments,it achieved accuracy rates of 0.999158 and 0.999091,respectively,surpassing other state-of-the-art methods.

关键词： Intrusion detection CNN BiLSTM BiGRU attention

七氟醚麻醉过程中mPFC脑区不同类型神经元胞外腺苷递质动态变化研究

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遵义医科大学学报 2024年第5期47卷 471-477页

作者：汪莹刘继徐茂王家敏王袁罗天元余守洋遵义医科大学贵州省普通高等学校脑科学特色重点实验室贵州遵义563006 贵州省麻醉与器官保护基础研究重点实验室贵州遵义563006 遵义医科大学附属医院麻醉科贵州遵义563003

目的探究在七氟醚麻醉致意识消失与恢复过程中内侧前额叶皮层(mPFC)中谷氨酸能的锥体(Pyr)神经元与γ-氨基丁酸(GABA)能神经元的两种亚型:小清蛋白(PV)阳性神经元与生长抑素(SST)阳性神经元胞外腺苷释放的动态变化情况。方法在C57小鼠(n... 详细信息

目的探究在七氟醚麻醉致意识消失与恢复过程中内侧前额叶皮层(mPFC)中谷氨酸能的锥体(Pyr)神经元与γ-氨基丁酸(GABA)能神经元的两种亚型:小清蛋白(PV)阳性神经元与生长抑素(SST)阳性神经元胞外腺苷释放的动态变化情况。方法在C57小鼠(n=6)mPFC脑区注射AAV-CaMkⅡα-Cre与AAV-DIO-Ado1.0混合病毒,SST-IRES-Cre小鼠(n=6)与PV-IRES-Cre小鼠(n=6)mPFC脑区注射AAV-DIO-Ado1.0病毒,待病毒转染3周。在本实验中主要使用多通道光纤记录系统记录腺苷的荧光信号强度。记录给予2.3%七氟醚麻醉时小鼠从清醒到翻正反射消失,以及翻正反射恢复到完全苏醒过程中腺苷的动态变化情况。结果七氟醚能够引起mPFC中锥体神经元、SST神经元、PV神经元胞外腺苷的增加,并随着七氟醚的停止吸入未立即下降。结论mPFC脑区可能通过调控腺苷传递参与七氟醚麻醉致意识的改变。

关键词：内侧前额叶皮层七氟醚全身麻醉腺苷

《中国叙事医学专家共识(2023)》的德尔菲法研究

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叙事医学 2024年第2期7卷 105-112页

作者：胡卓慕吴进方珍茹毛旭郭莉萍朱利明杭州师范大学公共卫生学院浙江省肿瘤医院北京大学医学人文学院

目的应用改良德尔菲法构建《中国叙事医学专家共识(2023)》,以进一步规范叙事医学本土化的理论框架、研究方法和实践形式,为我国叙事医学的发展提供支撑。方法基于文献检索,制定初始的德尔菲专家咨询问卷。选取21名专家进行2轮咨询,对... 详细信息

目的应用改良德尔菲法构建《中国叙事医学专家共识(2023)》,以进一步规范叙事医学本土化的理论框架、研究方法和实践形式,为我国叙事医学的发展提供支撑。方法基于文献检索,制定初始的德尔菲专家咨询问卷。选取21名专家进行2轮咨询,对共识内容进行修改,并采用SPSSPRO软件对结果进行分析。结果2轮德尔菲专家咨询的积极系数分别是72.41%和100%,权威系数在0.808~0.860之间;变异系数第1轮介于0.089~0.310之间,第2轮介于0.045~0.111之间;协调系数第1轮为0.107,第2轮为0.132,均具有统计学意义(P<0.05)。最终确定3个维度,共21条推荐意见。结论本研究是运用德尔菲法制定的首个中国叙事医学专家共识,为叙事医学的本土化发展提供了参考,有助于叙事医学研究及实践的规范化和体系化发展。

关键词：叙事医学改良德尔菲法专家共识