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复杂场景下间歇采样转发干扰抑制算法
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作者 安强 叶春茂 +1 位作者 鲁耀兵 张彦 《系统工程与电子技术》 北大核心 2025年第2期463-477,共15页
间歇采样转发干扰(interrupted sampling repeater jamming, ISRJ)是一种对现代雷达系统构成重大威胁的相干干扰方式。在高干扰时域占空比、弱能量干扰等复杂场景下,ISRJ干扰切片相互遮掩且能量接近真实目标,这将导致传统时/频域算法干... 间歇采样转发干扰(interrupted sampling repeater jamming, ISRJ)是一种对现代雷达系统构成重大威胁的相干干扰方式。在高干扰时域占空比、弱能量干扰等复杂场景下,ISRJ干扰切片相互遮掩且能量接近真实目标,这将导致传统时/频域算法干扰抑制效果大幅下降以至失效。针对该问题,从ISRJ时频耦合机理入手,提出一种新的针对复杂场景优化的ISRJ抑制算法,该算法遵循“解耦-滤波-重构”流程处理含干扰回波。首先,通过时频解耦变换,将干扰多组转发切片对齐,以有效降低干扰的时域占空比。然后,通过噪声区域的划分,采用低门限原则对时频图进行二值化处理。随后,采用最保守原则生成时域遮罩,滤除干扰。最后,通过间断CLEAN技术处理重构完整目标回波。多组仿真实验验证所提算法的有效性,分析多组参数变化对其性能的影响,并评估了算法的实时性。理论分析和仿真结果共同证实,相较于传统的基于滤波的抗ISRJ算法,所提算法可以在大干扰时域占空比、弱能量干扰等复杂场景下,展现出更为优越的干扰抑制性能。 展开更多
关键词 间歇采样转发干扰 CLEAN技术 时频分析 解调频处理
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基于改进Clean算法的ISAR像目标轮廓提取方法
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作者 范宇哲 范林刚 +1 位作者 张志衡 陈成增 《现代防御技术》 北大核心 2025年第2期156-166,共11页
针对逆合成孔径雷达(inverse synthetic aperture radar,ISAR)图像目标轮廓特征提取的现有方法精度不高的问题,提出了一种基于改进Clean算法的ISAR像目标轮廓提取方法。先根据噪声随机出现的特点,建立散射点提取优化函数,并通过迭代Clea... 针对逆合成孔径雷达(inverse synthetic aperture radar,ISAR)图像目标轮廓特征提取的现有方法精度不高的问题,提出了一种基于改进Clean算法的ISAR像目标轮廓提取方法。先根据噪声随机出现的特点,建立散射点提取优化函数,并通过迭代Clean方法尽可能提取更多的微弱散射点;针对Clean算法的后处理,采用了基于连通性分析的散射点质量评估方法,对Clean算法提取的散射点进行去噪,并保留目标本体的散射点集;最后对散射点集,使用Alpha-Shape和小波滤波处理获得目标轮廓。仿真和实测数据处理结果表明,所提方法和现有的轮廓提取方法相比,轮廓特征提取精度更高,且抗噪声性能更好。 展开更多
关键词 逆合成孔径雷达图像 轮廓提取 CLEAN算法 优化迭代 噪点去除
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Interface energetics in organic and perovskite semiconductor solar cells 被引量:1
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作者 Shaobing Xiong Mats Fahlman Qinye Bao 《Journal of Semiconductors》 2025年第5期14-18,共5页
Improving the quality of life for Earth's growing population is a complex task that requires the development of new technologies and materials. Perhaps the biggest challenge is access to clean and renewable energy... Improving the quality of life for Earth's growing population is a complex task that requires the development of new technologies and materials. Perhaps the biggest challenge is access to clean and renewable energy sources that can drive a sustainable future. Photovoltaics, today mainly represented by silicon-based solar cells, convert solar energy into electricity and is already an important component in the renewable energy portfolio. 展开更多
关键词 access clean renewable energy sources perovskite solar cells development new technologies materials renewable energy portfolio organic solar cells clean energy improving quality life renewable energy
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ON POTENT ELEMENTS AND PSEUDO CLEAN RINGS
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作者 DING Yan GAO Han-peng +2 位作者 LIU Xin-yi YAN Zi-yi ZHANG Ting 《数学杂志》 2025年第1期39-47,共9页
In this paper,potent index of an element and pseudo clean rings are considered.Some properties and examples of pseudo clean rings are given.We also show that Zm is pseudo clean for every 2≤m∈Z and pseudo clean rings... In this paper,potent index of an element and pseudo clean rings are considered.Some properties and examples of pseudo clean rings are given.We also show that Zm is pseudo clean for every 2≤m∈Z and pseudo clean rings are clean.Furthermore,we prove pseudo clean rings are directly finite and have stable range one. 展开更多
关键词 clean rings strongly J-clean rings pseudo clean rings potent elements
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The City of Well-Being in China
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作者 李明瑞 张超(指导) 《中学生英语》 2025年第19期7-7,共1页
Shijiazhuang,the capital of Hebei,is a reallyhappy city.It is often called the city of well-beingin China.The city has a nice living environment.Thereare lots of beautiful parks where people can walk,exercise,or just ... Shijiazhuang,the capital of Hebei,is a reallyhappy city.It is often called the city of well-beingin China.The city has a nice living environment.Thereare lots of beautiful parks where people can walk,exercise,or just relax on weekends.The air isgetting cleaner,and the streets are cleaner,too.Transportation in Shijiazhuang is very convenient.Subways,buses,and shared bikes can take youeverywhere.Shijiazhuang also has a rich culture. 展开更多
关键词 living environment clean streets convenient transportation Shijiazhuang clean air shared bikes beautiful parks well being city
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China-Portugal Green Strategic Synergy in Bluetech and Clean Energy Integration
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作者 Zhou Jie 《China Oil & Gas》 2025年第3期3-8,共6页
As global climate governance moves into the implementation phase,the integration of bluetech and clean energy has emerged as a key driver of green transition.On the occasion of the 50th anniversary of China-EU diploma... As global climate governance moves into the implementation phase,the integration of bluetech and clean energy has emerged as a key driver of green transition.On the occasion of the 50th anniversary of China-EU diplomatic relations,China and Portugal have built a multi-level cooperation framework in the“ocean+clean energy”domain,leveraging complementary resource endowments,technological synergies,and policy alignment. 展开更多
关键词 global climate governance china eu green transition integration bluetech clean energy green transitionon policy alignment clean energy diplomatic relations
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How to Deal with Climate Change?
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作者 王子妮 欧海贞(指导) 《中学生英语》 2025年第22期7-7,共1页
The 1.5℃ plays an important role on many aspects.It has to do with climate change.And these days,climate change is getting worse and worse.It is now one of the biggest problems in the world.But don’t worry-everyone ... The 1.5℃ plays an important role on many aspects.It has to do with climate change.And these days,climate change is getting worse and worse.It is now one of the biggest problems in the world.But don’t worry-everyone can help with it.First of all,we can plant more trees to cut down the air pollution.What’s more,we should use clean energy,such as wind energy,solar energy and so on. 展开更多
关键词 plant more trees solar energy air pollution wind energysolar energy clean energy clean energysuch climate changeand wind energy
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How To Clean a Microwave
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作者 Maria Chiu 《空中英语教室(初级版.大家说英语)》 2025年第10期10-11,50,共3页
Mix two tablespoons of white vinegar into a cup of water.Take out the turntable and wash it.Heat it in the microwave for three minutes.
关键词 CLEANING white vinegar TURNTABLE VINEGAR water MICROWAVE
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A Pleasant Sunday
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作者 李睿涵 张超(指导) 《中学生英语》 2025年第29期7-7,共1页
I had a pleasant Sunday last week.In the morning,I got up late and then began to do my homework.I spent nearly two hours on my homework.Next,I had fun watching a TV show.When my mom was cooking lunch,I cleaned the hou... I had a pleasant Sunday last week.In the morning,I got up late and then began to do my homework.I spent nearly two hours on my homework.Next,I had fun watching a TV show.When my mom was cooking lunch,I cleaned the house and washed my clothes.In the afternoon,I played table tennis happily with my best friend Kou Yu. 展开更多
关键词 TV show HOMEWORK friend SUNDAY clothes washing table tennis cleaning
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With Body and Heart Together,Robots Are“Awakening”
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作者 Liu Xinwei 《China's Foreign Trade》 2025年第2期34-36,共3页
Have you ever imagined that home robots can not only help you clean,but also read you,chat and play chess with you and even take good care of you when you are sick?These are no longer scenes in science fiction movies,... Have you ever imagined that home robots can not only help you clean,but also read you,chat and play chess with you and even take good care of you when you are sick?These are no longer scenes in science fiction movies,but reality that is happening.With the rapid development of Embodied Intelligence technology,robots are evolving from“tools”to“partners”.As cold machines are given“body temperature”,an intelligent revolution has begun quietly. 展开更多
关键词 cleaning embodied intelligence technologyrobots AWAKENING reading cold machines read youchat BODY HEART
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Automatic collaborative water surface coverage and cleaning strategy of UAV and USVs
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作者 Tianping Deng Xiaohui Xu +3 位作者 Zeyan Ding Xiao Xiao Ming Zhu Kai Peng 《Digital Communications and Networks》 2025年第2期365-376,共12页
As the problem of surface garbage pollution becomes more serious,it is necessary to improve the efficiency of garbage inspection and picking rather than traditional manual methods.Due to lightness,Unmanned Aerial Vehi... As the problem of surface garbage pollution becomes more serious,it is necessary to improve the efficiency of garbage inspection and picking rather than traditional manual methods.Due to lightness,Unmanned Aerial Vehicles(UAVs)can traverse the entire water surface in a short time through their flight field of view.In addition,Unmanned Surface Vessels(USVs)can provide battery replacement and pick up garbage.In this paper,we innovatively establish a system framework for the collaboration between UAV and USVs,and develop an automatic water cleaning strategy.First,on the basis of the partition principle,we propose a collaborative coverage path algorithm based on UAV off-site takeoff and landing to achieve global inspection.Second,we design a task scheduling and assignment algorithm for USVs to balance the garbage loads based on the particle swarm optimization algorithm.Finally,based on the swarm intelligence algorithm,we also design an autonomous obstacle avoidance path planning algorithm for USVs to realize autonomous navigation and collaborative cleaning.The system can simultaneously perform inspection and clearance tasks under certain constraints.The simulation results show that the proposed algorithms have higher generality and flexibility while effectively improving computational efficiency and reducing actual cleaning costs compared with other schemes. 展开更多
关键词 UAV USVs Collaborative cleaning Path planning COVERAGE Autonomous obstacle avoidance
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Efficacy of spray flushing in the reprocessing of flexible endoscopes
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作者 Harendra Kumar Arkadeep Dhali +1 位作者 Rick Maity Jyotirmoy Biswas 《World Journal of Gastrointestinal Endoscopy》 2025年第1期82-85,共4页
This article comments on the article by Du et al,who conducted a randomized controlled trial aiming at evaluating the effectiveness of a novel spray flushing system in cleaning flexible endoscopes while minimizing dam... This article comments on the article by Du et al,who conducted a randomized controlled trial aiming at evaluating the effectiveness of a novel spray flushing system in cleaning flexible endoscopes while minimizing damage to the working channels.We share our perspective on the importance of improving endoscope reprocessing methods.The findings highlight the spray flushing system's capacity to improve cleaning efficacy while minimizing damage,suggesting that it might be important in enhancing endoscope reprocessing procedures. 展开更多
关键词 Spray flushing ENDOSCOPE Flexible endoscope Endoscopy Endoscope cleaning Endoscope reprocessing
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Absolutely Clean N-Complexes
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作者 HAN Xia WANG Xin LU Bo 《Wuhan University Journal of Natural Sciences》 2025年第2期133-138,共6页
The notion of absolutely clean N-complexes is studied.We show that an N-complex X is absolutely clean if and only if X is Nexact and Z,(X)is an absolutely clean module for each n e Z and i=1,2,..,N.In particular,we pr... The notion of absolutely clean N-complexes is studied.We show that an N-complex X is absolutely clean if and only if X is Nexact and Z,(X)is an absolutely clean module for each n e Z and i=1,2,..,N.In particular,we prove that a bounded above N-complex X is absolutely clean if and only if X,is an absolutely clean module for each n e Z.We also show that under certain hypotheses,an Ncomplex X is Gorenstein AC-injective if and only if Z;(X)is a Gorenstein AC-injective module for each n e Z and t=1,2,.,N. 展开更多
关键词 absolutely clean module absolutely clean N-complex Gorenstein AC-injective N-complex
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Overview of the International Forum for Clean Energy(Macao)
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《China Oil & Gas》 2025年第4期F0003-F0003,共1页
Established in 2012,the International Forum for Clean Energy(Macao)(IFCE)is a leading global platform committed to advancing clean energy solutions.Strategically located at the crossroads of East and West,in Macao,the... Established in 2012,the International Forum for Clean Energy(Macao)(IFCE)is a leading global platform committed to advancing clean energy solutions.Strategically located at the crossroads of East and West,in Macao,the forum leverages its unique geographical and cultural position to foster international cooperation,innovation,and policy dialogue in the clean energy sector. 展开更多
关键词 MACAO international cooperation clean energy policy dialogue INNOVATION
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Wired for a New Drive Liuzhou’s EV ecosystem shows how affordability and innovation can steer the future of mobility
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作者 Antony Hardi 《China Report ASEAN》 2025年第5期52-53,共2页
Imagine a city that seems to hum rather than roar-a place where innovation moves at the pace of everyday life instead of like the flashy glamor of high-end tech hubs.This is Liuzhou,a city in southern China that is qu... Imagine a city that seems to hum rather than roar-a place where innovation moves at the pace of everyday life instead of like the flashy glamor of high-end tech hubs.This is Liuzhou,a city in southern China that is quietly shaping the future of electric vehicles(EVs).It has become an unlikely yet powerful engine of change in the world of clean mobility. 展开更多
关键词 electric vehicles AFFORDABILITY engine change Liuzhou clean mobility MOBILITY innovation electric vehicles evs
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Distribution and role of fluorine in the aquatic ecosystem(mineral springs,groundwater,tributaries,Baikal water,and the Angara water source)of Lake Baikal,Russia
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作者 Valentina Grebenshchikova Mikhail Kuzmin +1 位作者 Anna Novopashina Elena Kuz’mina 《China Geology》 2025年第2期303-313,共11页
Several conjugate components represent the aquatic ecosystem of Lake Baikal:Baikal water(surface and deep water),groundwater from boreholes,water of numerous Baikal tributaries,cold and hot mineral springs around Lake... Several conjugate components represent the aquatic ecosystem of Lake Baikal:Baikal water(surface and deep water),groundwater from boreholes,water of numerous Baikal tributaries,cold and hot mineral springs around Lake Baikal,and the Angara River,the only runoff reflecting all this aquatic diversity.River waters in the Baikal region are known to be deficient in some vital elements,including fluorine.This article discusses the features of the fluorine distribution in the water from the conjugate components of the Baikal ecosystem.Fluorine ion concentrations in the water of the Baikal ecosystem was determined using the potentiometric method.The study represents the monitoring that was carried out between 1997 and 2022 years.We determine likely causes of high and low fluorine concentrations in the water from different components,propose and substantiate the fluorine sources,geological and geochemical model of its influx and distribution features in the water of the Baikal ecosystem. 展开更多
关键词 Clean fresh water Aquatic ecosystem Concentration FLUORINE Sources Anthropogenic factor Formation model Lake Baikal
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Research Progress on Clean,Efficient,and Low-Carbon Utilization Technologies for Coal Combustion
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作者 Zhao Yongchun Zheng Chuguang 《China Oil & Gas》 2025年第1期15-18,共4页
Introduction In September 2020,President Xi Jinping announced China's goals of carbon peak and carbon neutrality.Compared to Europe and the United States,China faces a tighter timeline and a larger scale in achiev... Introduction In September 2020,President Xi Jinping announced China's goals of carbon peak and carbon neutrality.Compared to Europe and the United States,China faces a tighter timeline and a larger scale in achieving its dual carbon goals,making the task exceptionally demanding. 展开更多
关键词 CLEAN exceptional goals
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Turning on the Taps
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作者 DERRICK SILIMINA 《ChinAfrica》 2025年第7期48-49,共2页
Chinese-built project delivers clean water to over 450,000 people in Tanzanian capital city For years,Hassan Juma has struggled to secure clean water for his family in Dar es Salaam’s southern suburb of Bangulo.Like ... Chinese-built project delivers clean water to over 450,000 people in Tanzanian capital city For years,Hassan Juma has struggled to secure clean water for his family in Dar es Salaam’s southern suburb of Bangulo.Like many in the sprawling coastal city,he has faced persistent water shortages and has been forced to rely on expensive private vendors to meet his household’s basic needs. 展开更多
关键词 clean water water shortage dar es salaam private vendors bangulo
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Overview of the International Forum for Clean Energy(Macao)
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《China Oil & Gas》 2025年第1期100-100,共1页
IFCE International Forum for Clean Energy(Macao)Research Think Tank Technological Innovation Investment Collaboration Market Development Established in 2012,the International Forum for Clean Energy(Macao)(IFCE)is a le... IFCE International Forum for Clean Energy(Macao)Research Think Tank Technological Innovation Investment Collaboration Market Development Established in 2012,the International Forum for Clean Energy(Macao)(IFCE)is a leading global platform committed to advancing clean energy solutions. 展开更多
关键词 CLEAN FORUM MACAO
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Policy,Technology,and Capital Drivers of Clean Energy Cooperation under CAFTA 3.0:The China-ASEAN Experience
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作者 Zhou Jie 《China Oil & Gas》 2025年第4期4-11,共8页
This paper systematically reviews the institutional evolution of the China-ASEAN Free Trade Area(CAFTA),from its inception in 2002 and full establishment in 2010,through the CAFTA 2.0 upgrade in 2015,to the substantiv... This paper systematically reviews the institutional evolution of the China-ASEAN Free Trade Area(CAFTA),from its inception in 2002 and full establishment in 2010,through the CAFTA 2.0 upgrade in 2015,to the substantive conclusion of CAFTA 3.0 negotiations in 2024.It highlights the key institutional innovations along this trajectory and examines the structural complementarities between China and ASEAN in terms of clean energy resources and industrial capabilities.Based on this foundation,the paper develops a“policy-technology-capital”analytical framework to explain the transition of regional clean energy cooperation from initial resource-industry complementarity toward deeper institution-market integration.Guided by this framework,the study proposes a roadmap and concrete policy recommendations for regional cooperation through 2030.These include:aligning regional emissions targets and renewable energy share goals;establishing a mutual recognition system for green standards;building a digitalized green supply chain and carbon traceability platform;designing cross-border green finance corridors;and constructing integrated electricity-hydrogen-storage corridors in synergy with the Belt and Road Initiative.The study concludes that,if effectively implemented,these measures could raise the regional share of renewable electricity generation to over 30%by 2030.China and ASEAN would then be well positioned to lead in forming a low-carbon,interconnected,and shared regional energy community,offering a replicable and scalable model for low-carbon transition across the Global South. 展开更多
关键词 TECHNOLOGY China ASEAN POLICY clean energy resources CAFTA structural complementarities institutional innovations institutional evolution
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