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The Design of Wheelchair Lifting Mechanism and Control System 被引量:2
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作者 ZHAO Cong WANG Zheng-xing +2 位作者 JIANG Shi-hong ZHANG Li LIU Zheng-yu 《Computer Aided Drafting,Design and Manufacturing》 2014年第2期43-47,共5页
In order to achieve a wheelchair lift function, this paper designs a tri-scissors mechanism. Through the so-called H-type transmission and L-type swing rod, the three scissors mechanisms lift in the same rate with onl... In order to achieve a wheelchair lift function, this paper designs a tri-scissors mechanism. Through the so-called H-type transmission and L-type swing rod, the three scissors mechanisms lift in the same rate with only one liner motor while ensuring the stability of the lift. Finite element analysis in ANSYS is performed to verify the material strength. The control system with Sunplus SCM achieves the voice control of wheelchair walking and lifting. 展开更多
关键词 wheelchair lift scissors mechanism ANSYS analysis Sunplus SCM
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Chair's Introduction to 2009 IEEE Circuits and Systems International Conference on Testing and Diagnosis
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作者 Rueywen Liu 《Journal of Electronic Science and Technology of China》 2009年第4期289-289,共1页
Based on the recommendation of ICTD'09 TPC members, this Special Issue of the Journal of Electronic Science & Technology of China (JESTC) contained 22 high quality papers selected from the Proceedings of 2009 IEEE... Based on the recommendation of ICTD'09 TPC members, this Special Issue of the Journal of Electronic Science & Technology of China (JESTC) contained 22 high quality papers selected from the Proceedings of 2009 IEEE Circuits and Systems International Conference on Testing and Diagnosis (ICTD '09) which is fully sponsored by the IEEE Circuits and Systems Society (CASS), and is technically co-sponsored by the University of Electronic Science and Technology of China (UESTC), the Chinese Institute of Electronics (CIE), the China Instrument & Control Society (CIS), and organized by UESTC. 展开更多
关键词 IEEE this Chair’s Introduction to 2009 IEEE Circuits and Systems International Conference on Testing and Diagnosis
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The design of multi-function nursing wheelchair 被引量:2
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作者 LI Xiaoman WANG Zhengxing +2 位作者 ZHANG Shuai LI Fei ZHANG Li 《Computer Aided Drafting,Design and Manufacturing》 2013年第1期68-70,共3页
In order to reduce nursing intensity and improve freedom of the elderly and the disabled, a multi-function nursing wheelchair which can switch chair to bed and realize many kinds of posture transformation is designed.... In order to reduce nursing intensity and improve freedom of the elderly and the disabled, a multi-function nursing wheelchair which can switch chair to bed and realize many kinds of posture transformation is designed. This paper introduces the mechanical structure design (position adjustment mechanism and variable wheelbase mechanism) and control design of posture transformation unit of multifunctional nursing wheelchair. 展开更多
关键词 posture transformation position adjustment mechanism variable wheelbase the control system design
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PCIM, A Bridge Connecting China and World Power Electronics Industry ——Interview with Mr·Udo Weller,president of Mesago PCIM and Dr·Lorenz, General Chair of PCIM China [Honorary advisor of power Electronics]
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作者 Mr.Udo Weller Dr.Lorenz 《电力电子》 2006年第2期17-20,22,共5页
PCIM China, international conference and exhibition for power electronics, was held in Shanghai on March 21, 2006. PCIM is one of the most authoritative organizations and has won good reputation overseas for a long time.
关键词 电子工业 权威组织 PCIM 中国 发展计划
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Chairs’ Introduction to APOS2008——The 1st Asia-Pacific Optical Fiber Sensors Conference
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作者 Yun-Jiang Rao 《Journal of Electronic Science and Technology of China》 2008年第4期351-352,共2页
This special issue in the Journal of Electronic Science & Technology of China (JESTC) contains the selected papers presented at the 1st Asia-Pacific Optical Fiber Sensors Conference (APOS2008) organized by Univer... This special issue in the Journal of Electronic Science & Technology of China (JESTC) contains the selected papers presented at the 1st Asia-Pacific Optical Fiber Sensors Conference (APOS2008) organized by University of Electronic Science and Technology of China and Chongqing University, China. This conference is supported by Ministry of Education of the People's Republic of China, National Nature Science Foundation of China (NSFC), and Chinese Optics Society (COS). 展开更多
关键词 APOS2008 亚太光纤敏感器探讨会 电子技术 国际合作
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压气机内部旋转不稳定的研究综述
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作者 楚武利 陈向艺 《推进技术》 EI CAS CSCD 北大核心 2024年第5期1-15,共15页
旋转不稳定是压气机工作在高负荷近失速工况时的一种常见现象。研究旋转不稳定在降低压气机工作噪声、减小流致振动以及保障航空发动机稳定工作等方面具有重要意义。首先对旋转不稳定现象进行了回顾,详细讨论了旋转不稳定的特征。其次,... 旋转不稳定是压气机工作在高负荷近失速工况时的一种常见现象。研究旋转不稳定在降低压气机工作噪声、减小流致振动以及保障航空发动机稳定工作等方面具有重要意义。首先对旋转不稳定现象进行了回顾,详细讨论了旋转不稳定的特征。其次,重点调研了旋转不稳定的起源和机理,将旋转不稳定产生的原因归纳为叶尖泄漏流、涡脱落以及流动剪切等类别。此外,回顾了模拟旋转不稳定的数值方法,讨论了多种流动控制手段对旋转不稳定的作用效果。最后,对旋转不稳定的研究现状进行了总结,对未来的研究趋势进行了展望。 展开更多
关键词 压气机 旋转不稳定 叶尖泄漏流 涡脱落 非定常流 数值模拟 流动控制 综述
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文化景观视野下个旧大冲采矿遗址群调查与价值研究
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作者 侯实 余林阳 +4 位作者 曾巧巧 杨星月 黄磊 蒋林昀 王慧涵 《自然与文化遗产研究》 2024年第4期50-62,共13页
以个旧工业遗产普查中新发现的一处规模较大且未被机械开采破坏的“大冲采矿遗址群”为对象,通过查阅文献对其开采历史进行追溯;采用倾斜摄影绘制调查图纸;基于多方循证,识别并标注出相关遗址、遗迹,并将其分为采矿遗址(包括草皮尖、硐... 以个旧工业遗产普查中新发现的一处规模较大且未被机械开采破坏的“大冲采矿遗址群”为对象,通过查阅文献对其开采历史进行追溯;采用倾斜摄影绘制调查图纸;基于多方循证,识别并标注出相关遗址、遗迹,并将其分为采矿遗址(包括草皮尖、硐尖、冲尖)与建筑遗址二类。从文化景观视角分析了其具有“人与自然长期互动”“物质与非物质要素相互印证”的特征,绘制出动态变化示意图。在此基础上,从开采技术的见证、重要工业文化景观、关联性遗产3个维度提炼出“大冲采矿遗址群”的核心价值,并提出整体保护的建议。 展开更多
关键词 个旧锡矿 采矿遗址群 工业遗产 文化景观
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传统手工业类活态遗产的整体保护与活态传承—以“先市酱油酿造作坊群”为例
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作者 侯实 沈平冰清 +3 位作者 赫永皓 冯健 陈科 马超 《自然与文化遗产研究》 2024年第5期21-31,共11页
位于四川省合江县先市镇的“先市酱油酿造作坊群”是“传统手工业类活态遗产”的典型代表。通过对“先市酱油酿造作坊群”的详细调查与持续跟踪,分析其“物质与非物质遗产结合、人与自然长期互动、持续演进”等典型特征,提炼出“中华民... 位于四川省合江县先市镇的“先市酱油酿造作坊群”是“传统手工业类活态遗产”的典型代表。通过对“先市酱油酿造作坊群”的详细调查与持续跟踪,分析其“物质与非物质遗产结合、人与自然长期互动、持续演进”等典型特征,提炼出“中华民族创造美好生活的见证、中国古代酱油酿造技艺的代表、西南山区酿造作坊类文化景观”的核心价值,总结了“先市酱油酿造作坊群”在整体保护与活态传承中的经验,分析了保护与传承中“变”与“不变”的遗产价值要素。 展开更多
关键词 手工业类活态遗产 整体保护 活态传承 先市酱油酿造
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乡村家庭尺度全景碳流模型构建及实证
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作者 张宇鑫 李宏庆 +2 位作者 杨铮 张晓青 薛冰 《农业资源与环境学报》 CAS CSCD 北大核心 2024年第5期1133-1143,共11页
开展乡村家庭尺度的碳研究对于制定精细化的乡村碳治理策略和实现可持续发展目标具有重要意义。本研究利用物质流方法构建了乡村家庭尺度全景碳流模型,提出家庭的自然边界、社会边界和经济边界等概念,并将家庭活动划分成生产活动、经营... 开展乡村家庭尺度的碳研究对于制定精细化的乡村碳治理策略和实现可持续发展目标具有重要意义。本研究利用物质流方法构建了乡村家庭尺度全景碳流模型,提出家庭的自然边界、社会边界和经济边界等概念,并将家庭活动划分成生产活动、经营活动和生活活动,以此架构了边界内活动及外界系统间的物质流和碳流。同时通过设立结构指标和效率指标构建了家庭碳流的评价指标体系,以衡量家庭碳排放量和碳排放价值,并以山东省淄博市的典型农耕兼业型家庭为例进行了实证分析。结果表明:家庭碳排放主要来源于能源使用,且各碳排放源的排放量差异较大;家庭投入和产出过程的碳排放量分别为44637 kg和4558 kg,碳汇过程的碳汇量为547 kg,循环过程的潜在碳排放量为1216 kg,投入过程的碳排放量远高于产出过程的碳排放量,并且碳汇和循环过程减少的碳排放量相对较低;家庭碳循环率、碳效率和人均碳排放量分别为21.0%、3.6元·kg^(-1)和12162 kg,虽然家庭碳排放水平不高,但仍有较大的减排潜力。因此,未来案例家庭应优化调整消费结构,选择低碳能源产品,采用绿色低碳生活方式,特别是对经营活动产生的厨余垃圾进行垃圾分类,加强绿色基础建设,增设餐厅垂直绿化,在美化景观的同时增加家庭碳汇。 展开更多
关键词 家庭代谢 家庭碳排放 物质流分析 碳流 人地关系
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ST-Map:an Interactive Map for Discovering Spatial and Temporal Patterns in Bibliographic Data 被引量:1
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作者 ZUO Chenyu XU Yifan +1 位作者 DING Lingfang MENG Liqiu 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第1期3-15,共13页
Getting insight into the spatiotemporal distribution patterns of knowledge innovation is receiving increasing attention from policymakers and economic research organizations.Many studies use bibliometric data to analy... Getting insight into the spatiotemporal distribution patterns of knowledge innovation is receiving increasing attention from policymakers and economic research organizations.Many studies use bibliometric data to analyze the popularity of certain research topics,well-adopted methodologies,influential authors,and the interrelationships among research disciplines.However,the visual exploration of the patterns of research topics with an emphasis on their spatial and temporal distribution remains challenging.This study combined a Space-Time Cube(STC)and a 3D glyph to represent the complex multivariate bibliographic data.We further implemented a visual design by developing an interactive interface.The effectiveness,understandability,and engagement of ST-Map are evaluated by seven experts in geovisualization.The results suggest that it is promising to use three-dimensional visualization to show the overview and on-demand details on a single screen. 展开更多
关键词 space-time cube bibliographic data spatiotemporal analysis user study interactive map
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A Review on Sources,Extractions and Analysis Methods of a Sustainable Biomaterial:Tannins 被引量:2
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作者 Antonio Pizzi Marie-Pierre Laborie Zeki Candan 《Journal of Renewable Materials》 EI CAS 2024年第3期397-425,共29页
Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly ... Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based products.They are a definite class of sustainable materials of the forestry industry.They have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several others.This review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and instrumental.It constitutes a basic but essential summary of what is necessary to know of these sustainable materials.In doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses. 展开更多
关键词 TANNINS FLAVONOIDS SOURCES extraction methods analysis methods
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Fracture network characterisation of the Balmuccia peridotite using drone-based photogrammetry,implications for active-seismic site survey for scientific drilling 被引量:1
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作者 Niccolo Menegoni Yuri Panara +3 位作者 Andrew Greenwood Davide Mariani Alberto Zanetti Gyorgy Hetenyi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期3961-3981,共21页
The presence of discontinuities(e.g.faults,fractures,veins,layering)in crystalline rocks can be challenging for seismic interpretations because the wide range of their size,orientation,and intensity,which controls the... The presence of discontinuities(e.g.faults,fractures,veins,layering)in crystalline rocks can be challenging for seismic interpretations because the wide range of their size,orientation,and intensity,which controls the mechanical properties of the rock and elastic wave propagation,resulting in equally varying seismic responses at different scales.The geometrical characterisation of adjacent outcrop discontinuity networks allows a better understanding of the nature of the subsurface rocks and aids seismic interpretation.In this study,we characterise the discontinuity network of the Balmuccia peridotite(BP)in the IvreaeVerbano Zone(IVZ),northwestern Italy.This geological body is the focus of the Drilling the Ivrea eVerbano zonE(DIVE),an international continental scientific drilling project,and two active seismic surveys,SEismic imaging of the Ivrea ZonE(SEIZE)and high-resolution SEIZE(Hi-SEIZE),which aim to resolve the subsurface structure of the DIVE drilling target through high-resolution seismic imaging.For fracture characterisation,we developed two drone-based digital outcrop models(DOMs)at two different resolutions(10^(-3)-10 m and 10^(-1)-10^(3)m),which allowed us to quantitatively characterise the orientation,size,and intensity of the main rock discontinuities.These properties affect the seismic velocity and consequently the interpretation of the seismic data.We found that(i)the outcropping BP discontinuity network is represented by three more sets of fractures with respect to those reported in the literature;(ii)the discontinuity sizes follow a power-law distribution,indicating similarity across scales,and(iii)discontinuity intensity is not uniformly distributed along the outcrop.Our results help to explain the seismic behaviour of the BP detected by the SEIZE survey,suggesting that the low P-wave velocities observed can be related to the discontinuity network,and provide the basic topological parameters(orientation,density,distribution,and aperture)of the fracture network unique to the BP.These,in turn,can be used for interpretation of the Hi-SEIZE seismic survey and forward modelling of the seismic response. 展开更多
关键词 Remote sensing Fracture intensity Digital outcrop model(DOM) Rock discontinuity Fault SEismic imaging of the Ivrea ZonE(SEIZE) IvreaeVerbano Zone(IVZ) Crystalline rock
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碳中和愿景下景区碳排放核算与零碳路径研究——以崇州市大雨村幸福里林盘景区为例
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作者 林水发 郑兆龙 +3 位作者 韩晖 刘洋 吴剑源 林剑艺 《生态经济》 北大核心 2024年第4期136-143,共8页
碳中和是人类面对气候变化危机的积极作为和共同追求。论文以四川省幸福里景区为研究对象,建立景区净碳排放估算体系,分析碳排放结构,提出实施路径,量化减碳量,实现景区内“零碳排”的目标。结果表明:(1)2018—2021年幸福里的净排放总量... 碳中和是人类面对气候变化危机的积极作为和共同追求。论文以四川省幸福里景区为研究对象,建立景区净碳排放估算体系,分析碳排放结构,提出实施路径,量化减碳量,实现景区内“零碳排”的目标。结果表明:(1)2018—2021年幸福里的净排放总量为92.53 tCO_(2)e、116.61 tCO_(2)e、587.85 tCO_(2)e、625.80 tCO_(2)e,民宿、餐饮等行业是碳排放量快速增长的主要原因。(2)2018—2019年,能源活动的碳排放以车辆消耗的汽油为主,占58.49%、57.21%。2020—2021年,能源活动的碳排放结构发生转变,电力消费占主导地位,占68.73%、66.70%。(3)加大可再生能源建设,推广低碳交通、建筑节能、农业低碳、资源循环、林业碳汇等措施,预计可减少碳排放量743.64 tCO_(2)e/a。研究结果为景区碳排放核算、减碳实施路径及低碳转型提供参考。 展开更多
关键词 碳中和愿景 碳排放核算 零碳景区 景区规划
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Effect of a negative DC bias on a capacitively coupled Ar plasma operated at different radiofrequency voltages and gas pressures
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作者 相垚君 王晓坤 +1 位作者 刘永新 王友年 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第5期62-71,共10页
The effect of a negative DC bias,|V_(dc)|,on the electrical parameters and discharge mode is investigated experimentally in a radiofrequency(RF)capacitively coupled Ar plasma operated at different RF voltage amplitude... The effect of a negative DC bias,|V_(dc)|,on the electrical parameters and discharge mode is investigated experimentally in a radiofrequency(RF)capacitively coupled Ar plasma operated at different RF voltage amplitudes and gas pressures.The electron density is measured using a hairpin probe and the spatio-temporal distribution of the electron-impact excitation rate is determined by phase-resolved optical emission spectroscopy.The electrical parameters are obtained based on the waveforms of the electrode voltage and plasma current measured by a voltage probe and a current probe.It was found that at a low|V_(dc)|,i.e.inα-mode,the electron density and RF current decline with increasing|V_(dc)|;meanwhile,the plasma impedance becomes more capacitive due to a widened sheath.Therefore,RF power deposition is suppressed.When|V_(dc)|exceeds a certain value,the plasma changes toα–γhybrid mode(or the discharge becomes dominated by theγ-mode),manifesting a drastically growing electron density and a moderately increasing RF current.Meanwhile,the plasma impedance becomes more resistive,so RF power deposition is enhanced with|V_(dc)|.We also found that the electrical parameters show similar dependence on|V_(dc)|at different RF voltages,andα–γmode transition occurs at a lower|V_(dc)|at a higher RF voltage.By increasing the pressure,plasma impedance becomes more resistive,so RF power deposition and electron density are enhanced.In particular,theα–γmode transition tends to occur at a lower|V_(dc)|with increase in pressure. 展开更多
关键词 RF capacitively coupled plasma DC-overlapped RF discharge power deposition discharge mode transition
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Isotope Tracking of Surface Water Groundwater Interaction in the Beninese Part of the Iullemeden Aquifer System
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作者 Houégnon Géraud Vinel Gbewezoun Samuel Yao Ganyaglo +4 位作者 Abdoukarim Alassane Samuel Boakye Dampare Gaya Salifou Orou Pete Alou Moussa Boukari Daouda Mama 《Journal of Water Resource and Protection》 CAS 2024年第7期489-501,共13页
The Kandi basin is located in northeast Benin (West Africa). This study is focused on the estimation of water fluxes exchanged between the river Niger (and its tributaries) and the transboundary Iullemeden Aquifer Sys... The Kandi basin is located in northeast Benin (West Africa). This study is focused on the estimation of water fluxes exchanged between the river Niger (and its tributaries) and the transboundary Iullemeden Aquifer System. In that framework, an innovative approach based on the application of the Bayesian Mixing Model (MixSIAR) analysis on water isotopes (oxygen-18, deuterium and tritium) was performed. Moreover, to assess the relevance of the model outputs, Pearson’s correlation and Principal Component Analysis (PCA) have been done. A complex relationship between surface water and groundwater has been found. Sixty percent (60%) of groundwater samples are made of more than 70% river water and rainwater;while 31.25% of surface water samples are made of about 84% groundwater. To safeguard sustainable water resources for the well-being of the local communities, surface water and groundwater must be managed as a unique component in the Kandi basin. 展开更多
关键词 BENIN West Africa Kandi basin Iullemeden Aquifer System Surface Water Groundwater Interaction
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Physics-Based Active Learning for Design Space Exploration and Surrogate Construction for Multiparametric Optimization
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作者 Sergio Torregrosa Victor Champaney +2 位作者 Amine Ammar Vincent Herbert Francisco Chinesta 《Communications on Applied Mathematics and Computation》 EI 2024年第3期1899-1923,共25页
The sampling of the training data is a bottleneck in the development of artificial intelligence(AI)models due to the processing of huge amounts of data or to the difficulty of access to the data in industrial practice... The sampling of the training data is a bottleneck in the development of artificial intelligence(AI)models due to the processing of huge amounts of data or to the difficulty of access to the data in industrial practices.Active learning(AL)approaches are useful in such a context since they maximize the performance of the trained model while minimizing the number of training samples.Such smart sampling methodologies iteratively sample the points that should be labeled and added to the training set based on their informativeness and pertinence.To judge the relevance of a data instance,query rules are defined.In this paper,we propose an AL methodology based on a physics-based query rule.Given some industrial objectives from the physical process where the AI model is implied in,the physics-based AL approach iteratively converges to the data instances fulfilling those objectives while sampling training points.Therefore,the trained surrogate model is accurate where the potentially interesting data instances from the industrial point of view are,while coarse everywhere else where the data instances are of no interest in the industrial context studied. 展开更多
关键词 Active learning(AL) Artificial intelligence(AI) OPTIMIZATION Physics based
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MXene-Based Elastomer Mimetic StretchableSensors: Design, Properties, and Applications 被引量:1
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作者 Poushali Das Parham Khoshbakht Marvi +5 位作者 Sayan Ganguly Xiaowu(Shirley)Tang Bo Wang Seshasai Srinivasan Amin Reza Rajabzadeh Andreas Rosenkranz 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期295-342,共48页
Flexible sensors based on MXene-polymer composites are highly prospective for next-generation wearable electronics used in human-machine interfaces.One of the motivating factors behind the progress of flexible sensors... Flexible sensors based on MXene-polymer composites are highly prospective for next-generation wearable electronics used in human-machine interfaces.One of the motivating factors behind the progress of flexible sensors is the steady arrival of new conductive materials.MXenes,a new family of 2D nanomaterials,have been draw-ing attention since the last decade due to their high electronic conduc-tivity,processability,mechanical robustness and chemical tunability.In this review,we encompass the fabrication of MXene-based polymeric nanocomposites,their structure-property relationship,and applications in the flexible sensor domain.Moreover,our discussion is not only lim-ited to sensor design,their mechanism,and various modes of sensing platform,but also their future perspective and market throughout the world.With our article,we intend to fortify the bond between flexible matrices and MXenes thus promoting the swift advancement of flexible MXene-sensors for wearable technologies. 展开更多
关键词 Flexible sensor 2D nanomaterials MXene Wearable and conductive Applications
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Quantitative and Qualitative Responses of Hydroponic Tomato Production to Different Levels of Salinity
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作者 Khalid A.Al-Gaadi Ahmed M.Zeyada +4 位作者 ElKamil Tola Abdullah M.Alhamdan Khalid A.M.Ahmed Rangaswamy Madugundu Mohamed K.Edrris 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第6期1311-1323,共13页
From economic and nutritional points of view,tomato is,historically,considered one of the most important crops.Without significant yield reduction,most commercial cultivars of tomato crops are sensitive to moderate lev... From economic and nutritional points of view,tomato is,historically,considered one of the most important crops.Without significant yield reduction,most commercial cultivars of tomato crops are sensitive to moderate levels of salinity.However,high levels of salt stress can negatively affect the yield and quality of tomato fruits.Therefore,this study was conducted to evaluate the yield and fruit quality of three tomato cultivars(Forester,Ghandowra-F1,and Feisty-Red)cultivated hydroponically,under three different levels of nutrient solution salinity.Evaluation of tomato fruits was performed based on quantity(number and weight of fruits,and total fruit yield),physical quality(color andfirmness),and chemical quality(refractometric index“Brix”,pH,EC,K^(+),Na^(+),and NO_(3)-).Experiments were conducted using three salinity levels of the nutrient solution with electrical conductivity values(dSm^(-1))of 2.5(control),6.0,and 9.5.Results showed that the studied tomato cultivars were significantly influenced by high salinity(9.5 dSm^(-1))in comparison to the low(2.5 dSm^(-1))and medium(6.0 dSm^(-1))levels of salinity.On average,the highest fruit weight per plant of 1944.84 g and total fruit yield of 4.42 kgm^(-2) were observed at the low salinity level;however,no significant differences were obtained in the two yield factors(single fruit weight and total fruit yield)for the low and medium salinity levels.On the other hand,a significant reduction in tomato yield(31%)was associated with the high salinity level compared to the yield at low and medium salinity levels.Results of physical quality parameters showed highly significant differences among all salinity levels.On average,the maximum value of color change(1.72)was associated with the medium salinity level,and the maximum value offirmness(9.61 Ncm^(-1))was recorded at the high salinity level.Salinity levels and tomato cultivars introduced significant differences in chemical quality parameters;however,no significant differences in these parameters were attributed to the low and medium salinity levels.The maximum value of pH was recorded for the combination of medium salinity and Forester cultivar.Moreover,the maximum values of Brix,EC,K^(+),Na^(+),and NO_(3)^(-) were recorded for the Ghandowra-F1 cultivar at the high salinity level.Unlike the Feisty-Red,the performance of the Forester and Ghandowra-F1 cultivars was found to be acceptable at the tested medium salinity level(6.0 dSm^(-1)). 展开更多
关键词 Quality CULTIVARS YIELD color firmness BRIX
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Assessment of Groundwater Physico-Chemical Quality in the Ouémé Delta (Southern-Benin)
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作者 Aoulatou Alassane Zakari Dadja Toyou Masamaéya Gnazou +5 位作者 Abdoukarim Alassane Kodjo Apelete Raoul Kpegli Ousmane Touré Boukari Bio Guidah Chabi Bénito Didier Koukpohounsi Daouda Mama 《Journal of Environmental Protection》 2024年第3期298-317,共20页
Groundwater resources are the main sources of water used to supply drinking water to the population of the Ouémé Delta via the Continental Terminal aquifer. Urbanization, population growth, and agricultural ... Groundwater resources are the main sources of water used to supply drinking water to the population of the Ouémé Delta via the Continental Terminal aquifer. Urbanization, population growth, and agricultural and industrial activities have resulted in a deterioration in the quality of these resources. To assess the quality of the delta’s groundwater and its suitability for human consumption and irrigation, a total of fourteen (14) physico-chemical parameters were analyzed in some forty existing water points between September 2020 and March 2021, using standard water analysis techniques. The values obtained were compared with the potability standards recommended by the World Health Organization (WHO) and the Republic of Benin and were subjected to statistical analysis (principal component analysis (PCA)). In addition, methods for determining the suitability of water for irrigation were used. The results showed that the waters are acidic to slightly neutral and influenced by ambient temperature. In addition, the waters are moderately mineralized, with conductivities (24 - 1205 μS/cm) in line with WHO standards. A comparison of the analytical results of the WHO (2017) and Benin (2001) standards indicates that the majority of the waters studied are of good quality for all the chemical parameters considered. Nevertheless, some samples show levels of nitrates (21%), potassium (14% to 16%), calcium (13%), ammonium (12%), nitrites (8%) and bicarbonates (10%) over their respective standards. The Wilcox and Riverside diagrams indicate that the majority of waters (90%) have excellent suitability for irrigation and no negative effect on soil fertilization. 展开更多
关键词 BENIN OuéméDelta GROUNDWATER Physico-Chemical Quality Consumption IRRIGATION
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Theoretical Assessment of Environmental Factors and Untreated Infectious Individuals in the Transmission Dynamics of Buruli ulcer
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作者 Codjo Cesaire Yadouleton Myriam Djoukwe Tapi +1 位作者 Judicael Deguenon Ghislain Emmanuel Sopoh 《Applied Mathematics》 2024年第8期477-498,共22页
Buruli ulcer is the third most common mycobacterial disease worldwide, posing a significant public health burden, especially in impoverished regions of West and Central Africa, such as Benin. The management of Buruli ... Buruli ulcer is the third most common mycobacterial disease worldwide, posing a significant public health burden, especially in impoverished regions of West and Central Africa, such as Benin. The management of Buruli ulcer (BU) in Africa is often hindered by limited resources, delays in treatment, and inadequate medical facilities. Additionally, a portion of the population does not seek hospital care, which facilitates the continued presence of the pathogen in the environment. This paper aims to investigate the role of environmental factors in the transmission of Buruli ulcer. We develop a mathematical model to describe the dynamics of Buruli ulcer transmission, incorporating the presence of the bacterium in the environment. Theoretical results are presented to demonstrate that the model is well-posed. We compute the equilibria, including the disease-free equilibrium and the endemic equilibrium, and study their stability. To achieve this, we derive a threshold parameter called the basic reproduction number ℛ0, which determines whether the disease will persist in a human population. If ℛ0is less than one, the disease will eventually die out;if ℛ0is greater than one, the disease will persist. Sensitivity analysis is performed to understand the impact of various parameters on the dynamics of Buruli ulcer transmission and to identify the parameters that influence the basic reproduction number ℛ0. Finally, numerical simulations are conducted to validate the theoretical results obtained from the mathematical analysis. 展开更多
关键词 Buruli Ulcer Mathematical Models EQUILIBRIA STABILITY
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