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MICROGRAVITY EXPERIMENTS OF TWO-PHASE FLOW PATTERNS ABOARD MIR SPACE STATION 被引量:4
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作者 赵建福 解京昌 +1 位作者 林海 胡文瑞 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2001年第2期151-159,共9页
A first experimental study on two-phase how patterns at a long-term, steady microgravity condition was conducted on board the Russian Space Station 'MIR' in August 1999. Carbogal and air are used as the liquid... A first experimental study on two-phase how patterns at a long-term, steady microgravity condition was conducted on board the Russian Space Station 'MIR' in August 1999. Carbogal and air are used as the liquid and the gas phase, respectively. Bubble, slug, slug-annular transitional, and annular hows are observed. A new region of annular how with lower liquid superficial velocity is discovered, and the region of the slug-annular transitional flow is wider than that observed by experiments on board the parabolic aircraft. The main patterns are bubble, slug-annular transitional and annular flows based on the experiments on board MIR space station. Some influences on the two-phase how patterns in the present experiments are discussed. 展开更多
关键词 two-phase flow microgravity fluid physics space experiment
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Advances in China Space Medical Experiment Research
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作者 CHEN Hailong LIU Zhaoxia +18 位作者 WANG Lidong DING Bai SHI Liujia WANG Chunyan MI Tao YU Hongqiang ZHAO Rui WANG Honghui CHEN Chao QU Lina MA Honglei JIANG Changhua LI Yongzhi WEI Ming LI Zhili XU Chong ZANG Peng CAO Ping LI Yinghui 《空间科学学报》 CAS CSCD 北大核心 2022年第4期786-794,共9页
In 2021,China Space Station(CSS)was assembled and constructed in-orbit,which provided a broad space platform for space medicine and space life sciences research.Space medicine focuses on the systematic risks that rest... In 2021,China Space Station(CSS)was assembled and constructed in-orbit,which provided a broad space platform for space medicine and space life sciences research.Space medicine focuses on the systematic risks that restrict long-term manned spaceflight.It carries out systematic research on the impact and countermeasure technology of long-term weightlessness on astronauts’health,space radiation on astronauts’health,behavior and ability,advanced on-orbit monitoring and medical disposal technology,and traditional space medical application technology by the space medicine experiment platform on human body and cell.It has accumulated valuable data on space environmental effects and human factors research,established a“human system risk”research system,obtained new knowledge and discoveries of space medicine,and explored countermeasure technologies of new characteristics.Moreover,a series of achievements have been made in the basic research on the mechanism of the special space environmental effect,which provides a solid foundation for the implementation of space missions. 展开更多
关键词 space medical experiment WEIGHTLESSNESS RADIATION Behavior Traditional medicine
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SJ-10 Recoverable Satellite for Space Microgravity Experiments
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作者 HU Wenrui KANG Qi +1 位作者 DUAN Enkui LONG Mian 《空间科学学报》 CAS CSCD 北大核心 2020年第5期648-654,共7页
SJ-10 is a recoverable scientific experiment satellite specially for the space experiments of microgravity physics science and space life science.This mission was officially started on 31 December 2012,and the satelli... SJ-10 is a recoverable scientific experiment satellite specially for the space experiments of microgravity physics science and space life science.This mission was officially started on 31 December 2012,and the satellite was launched on 6 April 2016.This paper introduces briefly the SJ-10 mission,the progress of SJ-10 engineering and the project constitution of sciences experiments onboard SJ-10.The purpose of this mission is to discover the law of matter movement and the rule of life activity that cannot be discovered on the ground due to the existence of gravity,and to know the acting mechanism on organisms by the complex radiation of space that cannot be simulated on the ground. 展开更多
关键词 Microgravity physics space life science space microgravity experiments Recoverable satellite
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China's Space Animal Experiments Obtained Achievements
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《Aerospace China》 1995年第2期26-26,共1页
Entering into the 1990s, Chinese scientists have made mice, drosophila and silkworm eggs experiments in space with satellites and achieved remarkable results. These animals were put in space environment units with the... Entering into the 1990s, Chinese scientists have made mice, drosophila and silkworm eggs experiments in space with satellites and achieved remarkable results. These animals were put in space environment units with the ability of adjusting pressure, temperature and moisture control, air conditioning and purifying as well as foods and water supply. After 8-days’ flight, all performance parameters were normal and met the design requirements. The two mice kept alive for 5 days and 10 hours 展开更多
关键词 China’s space Animal experiments Obtained Achievements
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基于CiteSpace的半夏泻心汤实验研究知识图谱分析 被引量:1
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作者 汪珺 黄娟 +2 位作者 周慧敏 王世友 王梦芳 《西部中医药》 2020年第8期61-65,共5页
目的:应用CiteSpace软件分析半夏泻心汤实验方面的研究情况,探索和发现半夏泻心汤在实验研究方面的热点。方法:检索中国知网中已发表的关于半夏泻心汤实验研究方面的文献,运用科学计量学工具CiteSpaceⅤ绘制半夏泻心汤实验研究知识图谱... 目的:应用CiteSpace软件分析半夏泻心汤实验方面的研究情况,探索和发现半夏泻心汤在实验研究方面的热点。方法:检索中国知网中已发表的关于半夏泻心汤实验研究方面的文献,运用科学计量学工具CiteSpaceⅤ绘制半夏泻心汤实验研究知识图谱,并进行文献关键词共现分析和聚类分析。结果:关键词共现聚类网络由133个节点,242条线组成,被分成15个聚类。研究热点是对半夏泻心汤治疗糖尿病胃轻瘫机制的研究、半夏泻心汤对胃肠运动影响的研究。结论:通过知识图谱分析了解半夏泻心汤实验研究方面的研究热点和发展趋势,为今后的实验研究和临床应用提供依据,从而更好地提高半夏泻心汤的临床应用价值。 展开更多
关键词 半夏泻心汤 实验研究 CITEspace 知识图谱
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Progress of Materials Science in Space Technology in China(2020-2022)
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作者 WEI Qiang LIU Yue XIA Chaoqun 《空间科学学报》 CAS CSCD 北大核心 2022年第4期812-823,共12页
In this paper,the main research work and related reports of materials science research in China’s space technology field during 2020-2022 are summarized.This paper covers Materials Sciences in Space Environment,Mater... In this paper,the main research work and related reports of materials science research in China’s space technology field during 2020-2022 are summarized.This paper covers Materials Sciences in Space Environment,Materials Sciences for Space Environment,Materials Behavior in Space Environment and Space experimental hardware for material investigation.With the rapid development of China’s space industry,more scientists will be involved in materials science,space technology and earth science researches.In the future,a series of disciplines such as space science,machinery,artificial intelligence,digital twin and big data will be further integrated with materials science,and space materials will also usher in new development opportunities. 展开更多
关键词 Materials sciences in space environment Materials sciences for space environment Materials behavior in space environment space experimental hardware for material investigation
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天地一体化网络虚拟仿真实验设计
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作者 贾蓉 张进 +3 位作者 龚科成 虞红芳 段景山 李龙江 《实验室研究与探索》 北大核心 2026年第1期85-91,共7页
针对网络工程专业传统实验教学中存在的实验场景单一、环境固化、内容陈旧及实验起点滞后等问题,结合科研成果和工程应用,构建了天地一体化网络虚拟仿真实验平台。该平台采用虚拟化仿真、链路建模和流量监测分析等技术,真实模拟了天地... 针对网络工程专业传统实验教学中存在的实验场景单一、环境固化、内容陈旧及实验起点滞后等问题,结合科研成果和工程应用,构建了天地一体化网络虚拟仿真实验平台。该平台采用虚拟化仿真、链路建模和流量监测分析等技术,真实模拟了天地一体化网络系统及其通信过程。通过设置“基础-提高-进阶”三层次实验任务,循序渐进地引导学生理解卫星通信基础知识,探索二层交换网络与三层路由网络架构下的复杂网络通信问题。实践表明,天地一体化网络虚拟仿真实验突破了时空局限,丰富了教学维度,提升了学生的工程实践能力和创新思维,为网络工程专业实验教学和人才培养提供了有效支撑。 展开更多
关键词 天地一体化网络 虚拟仿真实验 网络工程 实验教学
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Design of Cultural Experience Space From the Perspective of Ecological Aesthetics:A Case Study of Aixi Lake Beauty·Library 被引量:1
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作者 KUANG Ye 《Journal of Landscape Research》 2020年第5期23-25,33,共4页
Ecological aesthetics is the organic combination of ecology and aesthetics.It is the mainstream and basic form of aesthetics to integrate the ecological concepts of balance,system and entirety into the study of aesthe... Ecological aesthetics is the organic combination of ecology and aesthetics.It is the mainstream and basic form of aesthetics to integrate the ecological concepts of balance,system and entirety into the study of aesthetics.Cultural experience space is a new reading space with the characteristics of public cultural services.In this paper,Aixi Lake Beauty·Library is taken as research object,to analyze its design connotation and public effect from the perspective of ecological aesthetics.The research aims to explore a feasible way for the construction of urban cultural experience space. 展开更多
关键词 Cultural experience space Ecological aesthetics Aixi Lake Beauty·Library
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Space radiation and cardiovascular disease risk 被引量:2
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作者 Marjan Boerma Gregory A Nelson +3 位作者 Vijayalakshmi Sridharan Xiao-Wen Mao Igor Koturbash Martin Hauer-Jensen 《World Journal of Cardiology》 CAS 2015年第12期882-888,共7页
Future long-distance space missions will be associated with significant exposures to ionizing radiation,and the health risks of these radiation exposures during manned missions need to be assessed. Recent Earth-based ... Future long-distance space missions will be associated with significant exposures to ionizing radiation,and the health risks of these radiation exposures during manned missions need to be assessed. Recent Earth-based epidemiological studies in survivors of atomic bombs and after occupational and medical low dose radiation exposures have indicated that the cardiovascular system may be more sensitive to ionizing radiation than was previously thought. This has raised the concern of a cardiovascular disease risk from exposure to space radiation during long-distance space travel. Groundbased studies with animal and cell culture models play an important role in estimating health risks from space radiation exposure. Charged particle space radiation has dense ionization characteristics and may induce unique biological responses,appropriate simulation of the space radiation environment and careful consideration of the choice of the experimental model are critical. Recent studies have addressed cardiovascular effects of space radiation using such models and provided first results that aid in estimating cardiovascular disease risk,and several other studies are ongoing. Moreover,astronauts could potentially be administered pharmacological countermeasures against adverse effects of space radiation,and research is focused on the development of such compounds. Because the cardiovascular response to space radiation has not yet been clearly defined,the identification of potential pharmacological countermeasures against cardiovascular effects is still in its infancy. 展开更多
关键词 space RADIATION CARDIOVASCULAR DISEASE RISK experimentAL models COUNTERMEASURES Ionizing RADIATION
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Numerical and Experimental Studies on the Effect of Axial Spacing on Hydrodynamic Performance of the Hybrid CRP Pod Propulsion System 被引量:4
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作者 熊鹰 张可 +1 位作者 王展智 齐万江 《China Ocean Engineering》 SCIE EI CSCD 2016年第4期627-636,共10页
The hydrodynamic performance of a hybrid CRP pod propulsion system was studied by RANS method with SST k ?? turbulence model and sliding mesh. The effect of axial spacing on the hydrodynamic performance of the hybri... The hydrodynamic performance of a hybrid CRP pod propulsion system was studied by RANS method with SST k ?? turbulence model and sliding mesh. The effect of axial spacing on the hydrodynamic performance of the hybrid CRP pod propulsion system was investigated numerically and experimentally. It shows that RANS with the sliding mesh method and SST k -ω turbulence model predicts accurately the hydrodynamic performance of the hybrid CRP pod propulsion system. The axial spacing has little influence on the hydrodynamic performance of the forward propeller, but great influence on that of the pod unit. Thrust coefficient of the pod unit declines with the increase of the axial spacing, but the trend becomes weaker, and the decreasing amplitude at the lower advance coefficient is larger than that at the higher advance coefficient. The thrust coefficient and open water efficiency of the hybrid CRP pod propulsion system decrease with the increase of the axial spacing, while the torque coefficient keeps almost constant. On this basis, the design principle of axial spacing of the hybrid CRP pod propulsion system was proposed. 展开更多
关键词 hybrid CRP pod propulsion system axial spacing hydrodynamic performance numerical simulation experimental study
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Reflections on the Experience of Network Virtual Space FromPhenomenology of Technics
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作者 MA Wen-wu 《Journal of Philosophy Study》 2019年第10期610-615,共6页
People create network virtual space that is completely different from the real space through network information technologies.The characteristics of network virtual space are that the subject can obtain a similar real... People create network virtual space that is completely different from the real space through network information technologies.The characteristics of network virtual space are that the subject can obtain a similar real space experience.From the perspective of phenomenology of technics,in order to analyze the virtual space of the network,it is necessary to clear the phenomenological concepts,such as space,space experience,and virtual space experience,so as to know the type of network virtual space experience,explore the essential characteristics,and find solutions to the ethical conflicts in the virtual space experience of the network. 展开更多
关键词 the experience of network virtual space phenomenology of technics Don Ihde ethical conflicts and countermeasures
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The Experimental Satellite on Electromagnetism Monitoring 被引量:2
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作者 SHEN Xuhui 《空间科学学报》 CAS CSCD 北大核心 2014年第5期558-562,共5页
The Experimental Satellite on Electromagnetism Monitoring(ESEM) was proposed in 2003 and proved in 2013 after 10-years' scientific demonstration. The ESEM mission was proposed to be the first satellite of space-ba... The Experimental Satellite on Electromagnetism Monitoring(ESEM) was proposed in 2003 and proved in 2013 after 10-years' scientific demonstration. The ESEM mission was proposed to be the first satellite of space-based geophysical fields observation system in China with a lot of application prospects in earthquake science, geophysics, space sciences and so on. And coincide with the mission objectives, the satellite decides to use the Circular Sun Synchronous Orbit with an altitude of 507 km and descending node time at 14:00 LT. The payload assemble includes 8 instruments,Search-Coil Magnetometer, Electric Field Detector, High precision Magnetometer, GNSS occupation Receiver, Plasma Analyzer, Langmuir Probe, Energetic Particle Detector, and Three-frequency Transmitter. According to the planned schedule, the satellite is due to be launched in 2016–2017 and will be onboard operated for 5 years. 展开更多
关键词 experimentAL SATELLITE Electromagnetism MONITORING IONOSPHERIC PERTURBATION space SEGMENT Ground SEGMENT
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基于Kriging模型的瞬变工况下深沟球轴承结构优化设计
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作者 张泽琳 龙浩然 +2 位作者 王蕾 曹建华 夏绪辉 《机电工程》 北大核心 2026年第1期45-55,共11页
在瞬变工况下(如急加速),深沟球轴承会因惯性载荷增大和应力分布不均匀导致应力升高。针对这一问题,以深沟球轴承6208为研究对象,提出了一种融合瞬态动力学仿真、最佳填充空间试验设计(OPSD)、Kriging模型与多目标遗传算法(MOGA)的结构... 在瞬变工况下(如急加速),深沟球轴承会因惯性载荷增大和应力分布不均匀导致应力升高。针对这一问题,以深沟球轴承6208为研究对象,提出了一种融合瞬态动力学仿真、最佳填充空间试验设计(OPSD)、Kriging模型与多目标遗传算法(MOGA)的结构优化设计方法。首先,基于瞬态动力学分析建立了深沟球轴承多体动力学模型,通过节点动态等效应力分析揭示了钢球与内外圈接触区域的应力周期性波动规律,并设置了三种瞬变梯度工况,研究了加速度幅值对应力分布的影响,发现了最大应力随加速度增大而显著升高;然后,综合考虑了深沟球轴承在瞬变工况下各结构参数对应力的影响,选取了内、外圈沟道曲率半径系数和钢球直径作为设计变量,以深沟球轴承在瞬变工况下的最大等效应力和最大接触应力作为目标函数,结合最佳填充空间设计方法(OPSD),建立了设计变量与目标函数之间的Kriging响应面模型;最后,使用多目标遗传算法(MOGA)对深沟球轴承的设计参数进行了优化求解,得到了最优的设计参数组合,并对优化结果的可靠性进行了实验验证。研究结果表明:优化后的深沟球轴承最大等效应力从408.52 MPa降低至382.74 MPa,减少了6.31%;最大接触应力从451.61 MPa降低至415.05 MPa,减少了8.10%。该研究结果可为深沟球轴承的结构优化设计提供一种思路。 展开更多
关键词 滚动轴承 试验设计方法 KRIGING模型 瞬态动力学 最佳填充空间试验设计 多目标遗传算法 节点动态等效应力分析 多目标优化
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托辊间距与环境温度对输送带压陷滚动阻力的影响
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作者 赵晓霞 田鹏飞 +1 位作者 阴璇 孟文俊 《科学技术与工程》 北大核心 2025年第27期11598-11606,共9页
当前,关于带式输送机承载段支撑托辊间距对压陷滚动阻力影响的研究相对较少,而该方面的深入探究可为带式输送机节能降耗提供关键的理论依据,为研究托辊间距与环境温度对带式输送机压陷滚动阻力的影响规律,综合运用了理论分析、有限元建... 当前,关于带式输送机承载段支撑托辊间距对压陷滚动阻力影响的研究相对较少,而该方面的深入探究可为带式输送机节能降耗提供关键的理论依据,为研究托辊间距与环境温度对带式输送机压陷滚动阻力的影响规律,综合运用了理论分析、有限元建模、仿真分析与实验验证的方法,以织物芯输送带为研究对象,在Abaqus软件中构建输送带和托辊模型,模拟托辊间距在800~1200 mm、环境温度介于-10~30℃多种工况下进行仿真分析,得出仿真结果。最后为验证环境温度对压陷滚动阻力影响的仿真结果,进行了实验研究。经分析,获得如下主要结论:在环境温度为-10~30℃工况下,托辊间距从800 mm递增至1200 mm时,压陷滚动阻力值增幅均超过1.3%,在20℃工况下增幅超过5%,且应力值与阻力值均随温度升高而降低,不同托辊间距工况下,温度上升时二者下降趋势保持一致;实验研究结果表明在多种载荷下,压陷滚动阻力随温度增高呈下降趋势,将实验结果与仿真结果对比,发现曲线趋势基本相同,验证了仿真结果的正确性。 展开更多
关键词 带式输送机 压陷滚动阻力 托辊间距 环境温度 仿真分析 实验研究
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实验政治学的“仪器”思维与算法路径实现
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作者 褚尔康 田菊 《山西高等学校社会科学学报》 2025年第1期76-82,共7页
科学实验是人们为了实现预定的研究目的,在人工控制条件下对实验对象进行分析的科学方法,是人类获得知识、检验知识的一种实践形式。近年来,政治学研究领域兴起实验分析方法,其核心理念是基于相应的统计学分析方法,通过建构相应分析工... 科学实验是人们为了实现预定的研究目的,在人工控制条件下对实验对象进行分析的科学方法,是人类获得知识、检验知识的一种实践形式。近年来,政治学研究领域兴起实验分析方法,其核心理念是基于相应的统计学分析方法,通过建构相应分析工具所生产的数据集,实现以数据集对政治行为对象的模拟。这些分析工具引入对于社会现象多样性与因果关系复杂性因素分析的方法,实现了基于实验政治学特殊“仪器”思维的理论性探索与体系性建构,使得政治科学能够更有效深入地挖掘变量与结果之间的作用机制,从而进一步提升其量化分析的研究能力。在此背景下,实验政治学“仪器”思维“数字化”转向与“算法化”推进的重要意义,就是借助算法化数据化模型对真实对象的简化以及表征作用的揭示,使得在面对复杂现象过程中能够通过数字化虚拟性的“仪器”体系建构,助力政治科学研究科学化水平的提升。 展开更多
关键词 实验政治学 仪器思维 数字空间 算法化
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高精度可变推力离子推力器在轨飞行验证
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作者 胡竟 杨福全 +7 位作者 王成飞 谷增杰 陈娟娟 郭德洲 张欣怡 贾艳辉 吴辰宸 耿海 《推进技术》 北大核心 2025年第12期183-191,共9页
某试验卫星搭载2台10 cm口径可变推力离子推力器以交替工作的模式开展了300 km以下近地轨道空间环境下的宽范围变推力能力、长期工作可靠性及空间环境适应性的在轨飞行验证。基于离子推力器的变推力调节工作原理与在轨验证策略,对10 cm... 某试验卫星搭载2台10 cm口径可变推力离子推力器以交替工作的模式开展了300 km以下近地轨道空间环境下的宽范围变推力能力、长期工作可靠性及空间环境适应性的在轨飞行验证。基于离子推力器的变推力调节工作原理与在轨验证策略,对10 cm口径可变推力离子推力器在轨飞行数据进行了分析评价,并与地面测试数据进行了比对。结果表明:10 cm口径可变推力离子推力器的技术方案合理、可行,宽范围精细化连续变推力的调节措施正确、有效,推力器在轨工作参数与地面试验数据的一致性良好,性能参数及其变化规律符合设计要求,其在98.3~585.3 W功率内可实现1.39~20.05 mN的变推力调节,比冲控制在547~3 056 s内,15 mN及20 mN工作点的推力闭环精度均稳定在1%以内。截至2025年6月,离子推力器入轨飞行近两年时间,已累计点火工作约5 800 h,开关机超过10~4次,工作性能稳定,参数状态正常,无异常衰退迹象。 展开更多
关键词 试验卫星 变推力 离子推力器 在轨飞行 天地差异
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带式动态输棉称重系统的设计与试验分析
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作者 王庶 冯静安 +3 位作者 栗宇航 吕江峰 陈靖 保倩 《石河子大学学报(自然科学版)》 北大核心 2025年第3期283-287,共5页
针对传统籽棉静态称重在数据实时采集、处理及监测能力方面的不足,设计了带式动态输棉称重测量系统,搭建了可调节称重单元的输棉装置,基于称重传感器的测重原理设计了数据采集处理模块和上位机显示模块,并在此基础上通过试验研究了称重... 针对传统籽棉静态称重在数据实时采集、处理及监测能力方面的不足,设计了带式动态输棉称重测量系统,搭建了可调节称重单元的输棉装置,基于称重传感器的测重原理设计了数据采集处理模块和上位机显示模块,并在此基础上通过试验研究了称重托辊间距、负载与测量精度之间的关系。试验结果表明:减小称重托辊间距和增加负载可有效提高称重精度;在低负载条件下,当称重托辊之间的间距较大时,测量精度受到的影响更加明显,并且当两称重托辊间距为5 cm、负载大于2 kg时,测量误差≤2%,能够满足带式动态称重测量要求。 展开更多
关键词 籽棉 带式输送 动态称重 托辊间距 试验分析
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基于强度-正交色度颜色空间的线路监控视频亮度增强方法
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作者 宋宗莹 王文斌 +3 位作者 周希博 柴雪松 李健超 王宁 《铁道建筑》 北大核心 2025年第8期149-156,共8页
本文针对重载铁路线路关键区段夜间视频监控图像光照不足、对比度低、细节模糊等问题,提出了一种基于强度-正交色度颜色空间的改进图像亮度增强方法(Low Light Enhancement for Railway surveillance video image based on improved Col... 本文针对重载铁路线路关键区段夜间视频监控图像光照不足、对比度低、细节模糊等问题,提出了一种基于强度-正交色度颜色空间的改进图像亮度增强方法(Low Light Enhancement for Railway surveillance video image based on improved Color space transform method,LLERC)。该方法首先将输入图像从RGB(Red,Green,Blue)颜色空间转换至所提出的改进IOC(Intensity-Orthometric-Chroma)颜色空间,以提取其强度和正交色度信息。随后,利用改进的轻量化双路U-net提取IOC颜色空间图像的特征,并预测实现亮度增强所需的强度残差和色度调整量。最后,将上述强度残差与输入图像叠加,得到光照增强后的IOC颜色空间图像,再将其转换为RGB颜色空间图像输出。将LLERC应用于重载铁路试验段,结果表明:LLERC方法在对比度、图像自然度、图像亮度顺序差异等指标上均优于传统图像增强方法和主流深度学习方法,并能有效提升重载铁路夜间视频监控图像的清晰度和自然程度。 展开更多
关键词 重载铁路 图像亮度增强 试验研究 铁路监控视频 颜色空间转换 深度学习 U-net
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基于CPO-BP神经网络的双燃料发动机性能预测模型研究
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作者 张清 王闯 +2 位作者 莫清烈 李哲骏 姜峰 《广西科技大学学报》 2025年第5期1-9,共9页
针对天然气-柴油双燃料发动机参数标定复杂度高、传统标定方法成本高的问题,构建高精度性能预测模型,为发动机控制参数优化与节能减排提供技术支持。基于GT-Power软件构建的YC6K型双燃料发动机一维仿真模型,包含了进排气系统、缸内工作... 针对天然气-柴油双燃料发动机参数标定复杂度高、传统标定方法成本高的问题,构建高精度性能预测模型,为发动机控制参数优化与节能减排提供技术支持。基于GT-Power软件构建的YC6K型双燃料发动机一维仿真模型,包含了进排气系统、缸内工作过程、Wiebe燃烧模型等核心模块。通过外特性(最大误差4.2%)和推进特性(缸压曲线误差不超过4.0%)验证模型的可靠性。采用Sobol空间填充试验设计方法,在6个参数(转速、预喷正时、主喷正时、轨压、空燃比、预喷油量)自由组合中抽取260个样本点。将冠豪猪优化算法(crested porcupine optimizer,CPO)与BP神经网络结合,通过CPO算法动态调整权重/偏置,解决传统BP易陷入局部最优问题,实现对双燃料发动机性能的预测。 展开更多
关键词 GT-POWER 双燃料发动机 Sobol空间填充试验设计 CPO-BP神经网络
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间距可调的蔬菜移栽机仿真设计与试验
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作者 沈德战 张园 +2 位作者 赵振华 韦丽娇 张静 《现代农业装备》 2025年第6期84-94,共11页
针对现有蔬菜移栽作业适应性与效率低,固定行距移栽机无法满足多种蔬菜农艺要求的问题,研究设计了一种行间距可调的蔬菜移栽机。基于移栽农艺要求确定了整机的关键结构与技术参数;运用三维建模软件完成了移栽机的虚拟样机设计,其核心调... 针对现有蔬菜移栽作业适应性与效率低,固定行距移栽机无法满足多种蔬菜农艺要求的问题,研究设计了一种行间距可调的蔬菜移栽机。基于移栽农艺要求确定了整机的关键结构与技术参数;运用三维建模软件完成了移栽机的虚拟样机设计,其核心调距机构采用左右旋丝杆结构,可实现移栽行距在特定范围内调节。在此基础上,利用仿真软件对移栽机关键工作部件进行运动学及动力学仿真分析,验证了机构设计的合理性与可靠性,仿真结果表明移栽机构调距过程运行平稳无干涉。通过试制样机并进行田间试验,以栽植深度合格率及立苗合格率为评价指标。试验结果表明,该移栽机在不同设定行距下作业性能稳定,各项指标均符合蔬菜移栽的农艺要求,验证了仿真设计的正确性与机具的实用性。研究可为智能化、多功能移栽装备的研发提供理论参考与技术依据。 展开更多
关键词 蔬菜移栽机 间距可调 仿真分析 虚拟样机 试验研究
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