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Frontiers of Chemical Science and Engineering 2023年第7期17卷 830-839页

作者： Shan Jiang jianfeng xi Hongqi Dai Huining xiao Weibing Wu Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsNanjing Forestry UniversityNanjing 210037China Department of Chemical Engineering University of New BrunswickFredericton E3B 5A3Canada

A multi-functional porous paper-based material was prepared from grass pulp by simple pore-forming and green cross-linking *** a pore-forming agent,calcium citrate increased the porosity of the paper-based material from 30%to 69%while retaining the mechanical *** covalent cross-linking of citric acid between cellulose fibers improved both the wet strength and adsorption *** addition,owing to the introduction of high-content carboxyl groups as well as the construction of hierarchical micro-nano structure,the underwater oil contact angle was up to 165°.The separation efficiency of the emulsified oil was 99.3%,and the water flux was up to 2020 L·m^(–2)·h^(–1).The theoretical maximum adsorption capacities of cadmium ion,lead ion and methylene blue reached 136,229 and 128.9 mg·g^(–1),*** continuous purification of complex wastewater can be achieved by using paper-based materials combined with filtration *** work provides a simple,low cost and environmental approach for the treatment of complex wastewater containing insoluble oil,organic dyes,and heavy metal ions.

关键词： adsorption oil-water separation underwater superoleophobicity wastewater treatment

CToMP: a cycle-task-oriented memory protection scheme for unmanned systems

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Science China(Information Sciences) 2024年第6期67卷 399-417页

作者： Chengyan MA Ning xi Di LU Yebo FENG jianfeng MA School of Cyber Engineering Xidian University School of Computer Science and Technology Xidian University Department of Computer and Information Science University of Oregon

Memory corruption attacks(MCAs) refer to malicious behaviors of system intruders that modify the contents of a memory location to disrupt the normal operation of computing systems, causing leakage of sensitive data or perturbations to ongoing processes. Unlike general-purpose systems, unmanned systems cannot deploy complete security protection schemes, due to their limitations in size, cost and *** in unmanned systems are particularly difficult to defend against. Furthermore, MCAs have diverse and unpredictable attack interfaces in unmanned systems, severely impacting digital and physical sectors. In this paper, we first generalize, model and taxonomize MCAs found in unmanned systems currently, laying the foundation for designing a portable and general defense approach. According to different attack mechanisms,we found that MCAs are mainly categorized into two types — return2libc and return2shellcode. To tackle return2libc attacks, we model the erratic operation of unmanned systems with cycles and then propose a cycle-task-oriented memory protection(CToMP) approach to protect control flows from tampering. To defend against return2shellcode attacks, we introduce a secure process stack with a randomized memory address by leveraging the memory pool to prevent Shellcode from being executed. Moreover, we discuss the mechanism by which CTo MP resists the return-oriented programming(ROP) attack, a novel variant of return2libc attacks. Finally, we implement CTo MP on CUAV V5+ with Ardupilot and Crazyflie. The evaluation and security analysis results demonstrate that the proposed approach CTo MP is resilient to various MCAs in unmanned systems with low footprints and system overhead.

关键词： unmanned system memory corruption attack memory protection system security randomized memory address

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Fractional Gradient Descent RBFNN for Active Fault-Tolerant Control of Plant Protection UAVs

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2129-2157页

作者： Lianghao Hua jianfeng Zhang Dejie Li xiaobo xi School of Mechanical Engineering Yangzhou UniversityYangzhou225009China College of Intelligent Manufacturing Yangzhou Polytechnic InstituteYangzhou225009China School of Automation Nanjing University of Aeronautics and AstronauticsNanjing211106China

With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rejectioncontroller (ADRC) has been widely applied in various fields. However, in controlling plant protection unmannedaerial vehicles (UAVs), which are typically large and subject to significant disturbances, load disturbances andthe possibility of multiple actuator faults during pesticide spraying pose significant challenges. To address theseissues, this paper proposes a novel fault-tolerant control method that combines a radial basis function neuralnetwork (RBFNN) with a second-order ADRC and leverages a fractional gradient descent (FGD) *** integrate the plant protection UAV model’s uncertain parameters, load disturbance parameters, and actuatorfault parameters and utilize the RBFNN for system parameter identification. The resulting ADRC exhibits loaddisturbance suppression and fault tolerance capabilities, and our proposed active fault-tolerant control law hasLyapunov stability implications. Experimental results obtained using a multi-rotor fault-tolerant test platformdemonstrate that the proposed method outperforms other control strategies regarding load disturbance suppressionand fault-tolerant performance.

关键词： Radial basis function neural network plant protection unmanned aerial vehicle active disturbance rejection controller fractional gradient descent algorithm

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防撞护栏对公路风吹雪雪害作用机理研究

中外公路 2024年第4期44卷 239-246页

作者：彭国冬席建锋张思源李敏刘梓伟邢瑞民锡林郭勒盟乾图交通设计有限责任公司内蒙古锡林浩特026000 吉林大学交通学院吉林长春130022 内蒙古交通设计研究院有限责任公司内蒙古呼和浩特010010

随着中国交通强国战略的持续推进,高等级公路在路网中的比重持续增加,交通安全设施的布设数量也越来越多。内蒙古自治区锡林郭勒盟冬季漫长、风力强劲,是中国深受风吹雪灾害影响的典型地区之一,通过实地调查发现,因交通安全设施导致的... 详细信息

随着中国交通强国战略的持续推进,高等级公路在路网中的比重持续增加,交通安全设施的布设数量也越来越多。内蒙古自治区锡林郭勒盟冬季漫长、风力强劲,是中国深受风吹雪灾害影响的典型地区之一,通过实地调查发现,因交通安全设施导致的“道路雪阻”“视程障碍”等公路风吹雪雪害问题日益突出,严重制约了公路交通运输功能的有效发挥,严重影响了当地经济和社会发展。其中,防撞护栏诱发风吹雪雪害的路段数和严重程度远超其他交通安全设施。因此,该文基于锡林郭勒盟公路风吹雪雪害的实地调查与分析,通过计算机仿真的方法,主要研究作为公路交通安全设施的防撞护栏对整体式公路路基断面风速流场的影响与作用规律,弥补防撞护栏对风吹雪雪害形成机理研究方面的滞后与欠缺,同时也为中国风吹雪地区公路防撞护栏的布设与雪害防治提供理论依据。

关键词：交通安全设施防撞护栏风吹雪仿真分析

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Giant negative photoresistance of epitaxial manganite La2/3Ca1/3MnO3-δ film

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Science China(Information Sciences) 2015年第12期58卷 204-210页

作者： xi jianfeng ZHAO Kun NI Hao xiANG WenFeng FENG xin SUN Qi LU ZhiQing xiAO LiZhi State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of Petroleum

The La2/3Ca1/3Mn O3-δ film has been deposited on the(001) Sr Ti O3 substrate and its temperature-dependent photoconductive properties have been investigated from 80 to 300 K. The La2/3Ca1/3Mn O3-δfilm has a novel photoelectric property due to its oxygen-deficient structure. We observed laser-induced giant negative photoresistance of the sample in a wide temperature range. The change rate of negative photoresistance was nearly 100% at the low temperature when the sample was irradiated by 532 nm laser. In addition, this effect was sensitive to the power of laser irradiation. The oxygen-deficiency of La2/3Ca1/3Mn O3-δfilm seems to have an impact on the laser-induced resistance variation. The experimental results made the La2/3Ca1/3Mn O3-δfilm a promising application as a photoswitch device.

关键词： giant negative photoresistance oxygen-deficient photoswitch thin film manganite oxide

Single-cell characterization of major components of plant cell walls in situ by Raman spectroscopy

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Science China(Life Sciences) 2024年第8期67卷 1772-1774页

作者： Yujian Li Weiwei Shen xi Zhang Yaning Cui Yuanyuan Zhao Yayu Guo xiaojuan Li Shuizhong Wang Guoyong Song Pu Wang jianfeng Ma Jinxing Lin State Key Laboratory of Efficient Production of Forest Resources College of Biological Sciences and TechnologyBeijing Forestry UniversityBeijing 100083China Institute of Tree Development and Genome Editing Beijing Forestry UniversityBeijing 100083China National Engineering Research Center of Tree Breeding and Ecological Restoration College of Biological Sciences and TechnologyBeijing Forestry UniversityBeijing 100083China Beijing Key Laboratory of Lignocellulosic Chemistry Engineering Research Center of Forestry Biomass Materials and EnergyMinistry of EducationBeijing Forestry UniversityBeijing 100083China Beijing Advanced Innovation Center for Biomedical Engineering School of Biological Science and Medical EngineeringBeihang UniversityBeijing 100191China Key lab of Bamboo and Rattan Science&Technology International Center for Bamboo and RattanBeijing 100102China

Dear Editor,Plant cell walls are complex and dynamic structures that are mainly composed of polysaccharide polymers such as cellulose,hemicellulose,and pectin,in addition to substantial amounts of the non-saccharide polymer lignin(McFarlane et al.,2014;German et al.,2023).The components of cell walls are interconnected in various ways to form a complex,multilayered network structure(Wen et al.,2023).

关键词： walls cellulose characterization

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Variational Analysis Based on Proximal Subdifferential on Smooth Banach Spaces

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Acta Mathematica Sinica,English Series 2024年第2期40卷 595-618页

作者： xi Yin ZHENG Department of Mathematics Yunnan UniversityKunming 650091P.R.China

This paper first shows that for any p∈(1,2)there exists a continuously differentiable function f on l^(p)(and L^(p))such that the proximal subdifferential of f is empty everywhere,and hence it is not suitable to develop theory on proximal subdifferential in the classical Banach spaces l^(P)and L^(P) with p∈(1,2).On the other hand,this paper establishes variational analysis based on the proximal subdifferential in the framework of smooth Banach spaces of power type 2,which conclude all Hilbert spaces and all the classical spaces l^(P)and L^(P)with p∈(2,+∞).In particular,in such a smooth space,we provide the proximal subdifferential rules for sum functions,product functions,composite functions and supremum functions,which extend the basic results on the proximal subdifferential established in the framework of Hilbert *** of our main results are new even in the Hilbert space *** applications,we provide KKT-like conditions for nonsmooth optimization problems in terms of proximal subdifferential.

关键词： Smooth Banach space proximal subdifferential proximal normal cone KKT condition

Spatiotemporal variations in ecosystem services and their trade-offs and synergies against the background of the gully control and land consolidation project on the Loess Plateau,China

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Journal of Arid Land 2024年第1期16卷 131-145页

作者： WANG Jing WEI Yulu PENG Biao LIU Siqi LI jianfeng Key Laboratory of Degraded and Unused Land Consolidation Engineering Ministry of Natural and ResourcesXi'an 710075China Institute of Land Engineering and Technology Shaanxi Provincial Land Engineering Construction Group Co.Ltd.Xi'an 710021China School of Human Settlements and Civil Engineering Xi'an Jiaotong UniversityXi'an 710049China Shaanxi Key Laboratory of Land Consolidation Xi'an 710064China

Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implications for ecological protection and quality development of the Yellow River ***,in this study,we took Yan'an City,Shaanxi Province of China,as the study area,selected four typical ecosystem services,including soil conservation service,water yield service,carbon storage service,and habitat quality service,and quantitatively evaluated the spatiotemporal variation characteristics and trade-offs and synergies of ecosystem services from 2010 to 2018 using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)*** also analysed the relationship between the GCLC project and regional ecosystem service changes in various regions(including 1 city,2 districts,and 10 counties)of Yan'an City and proposed a coordinated development strategy between the GCLC project and the ecological *** results showed that,from 2010 to 2018,soil conservation service decreased by 7.76%,while the other three ecosystem services changed relatively little,with water yield service increasing by 0.56% and carbon storage service and habitat quality service decreasing by 0.16% and 0.14%,*** ecological environment of Yan'an City developed in a balanced way between 2010 and 2018,and the four ecosystem services showed synergistic relationships,among which the synergistic relationships between soil conservation service and water yield service and between carbon storage service and habitat quality service were *** GCLC project had a negative impact on the ecosystem services of Yan'an City,and the impact on carbon storage service was more *** study provides a theoretical basis for the scientific evaluation of the ecological benefits of the GCLC project and the realization of a win-win situation between food security and e

关键词： ecosystem services trade-offs and synergies gully control and land consolidation habitat quality Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model Loess Plateau

A Generalized Blow up Criteria with One Component of Velocity for 3D Incompressible MHD System

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 253-264页

作者： Bin HAN xi xiONG Department of Mathematics Hangzhou Dianzi UniversityHangzhou 310018China

In this paper,the authors study the global regularity of the 3D magnetohydrodynamics system in terms of one velocity *** particular,they establish a new Prodi-Serrin type regularity criterion in the framework of weak ... 详细信息

关键词： MHD Regularity Blow-up criterion

A review of the neurotransmitter system associated with cognitive function of the cerebellum in Parkinson's disease

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Neural Regeneration Research 2024年第2期19卷 324-330页

作者： xi Chen Yuhu Zhang Department of Neurology Guangdong Neuroscience InstituteGuangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhouGuangdong ProvinceChina Shantou University Medical College ShantouGuangdong ProvinceChina

The dichotomized brain system is a concept that was generalized from the‘dual syndrome hypothesis’to explain the heterogeneity of cognitive impairment,in which anterior and posterior brain systems are independent but partially *** dopaminergic system acts on the anterior brain and is responsible for executive function,working memory,and *** contrast,the cholinergic system acts on the posterior brain and is responsible for semantic fluency and visuospatial *** from dopaminergic/cholinergic imaging or functional neuroimaging has shed significant insight relating to the involvement of the cerebellum in the cognitive process of patients with Parkinson’s *** research has reported evidence that the cerebellum receives both dopaminergic and cholinergic ***,whether these two neurotransmitter systems are associated with cognitive function has yet to be fully ***,the precise role of the cerebellum in patients with Parkinson’s disease and cognitive impairment remains ***,in this review,we summarize the cerebellar dopaminergic and cholinergic projections and their relationships with cognition,as reported by previous studies,and investigated the role of the cerebellum in patients with Parkinson’s disease and cognitive impairment,as determined by functional *** findings will help us to understand the role of the cerebellum in the mechanisms underlying cognitive impairment in Parkinson’s disease.

关键词： anterior brain system cerebellum cholinergic cognitive impairment dopaminergic dual syndrome hypothesis neuroimage neurotransmitter Parkinson’s disease posterior brain system therapeutic targets