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Analysis of factors influencing carbon emissions in the Yangtze River Delta region and projections of carbon peak scenarios 被引量:1
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作者 SHI Xiong-tian WU Feng-qing +1 位作者 CHEN Yang DAI Li-li 《Ecological Economy》 2024年第1期2-24,共23页
Based on the supply-side perspective,the improved STIRPAT model is applied to reveal the mechanisms of supply-side factors such as human,capital,technology,industrial synergy,institutions and economic growth on carbon... Based on the supply-side perspective,the improved STIRPAT model is applied to reveal the mechanisms of supply-side factors such as human,capital,technology,industrial synergy,institutions and economic growth on carbon emissions in the Yangtze River Delta(YRD)through path analysis,and to forecast carbon emissions in the YRD from the baseline scenario,factor regulation scenario and integrated scenario to reach the peak.The results show that:(1)Jiangsu's high carbon emission pattern is the main reason for the YRD hindering the synergistic regulation of carbon emissions.(2)Human factors,institutional factors and economic growth factors can all contribute to carbon emissions in the YRD region,while technological and industrial factors can generally suppress carbon emissions in the YRD region.(3)Under the capital regulation scenario,the YRD region has the highest level of carbon emission synergy,with Jiangsu reaching its peak five years earlier.Under the balanced regulation scenario,the YRD region as a whole,Jiangsu,Zhejiang and Anhui reach the peak as scheduled. 展开更多
关键词 Yangtze River Delta carbon peaking scenario forecasting STIRPAT model
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Combined Optimal Dispatch of Thermal Power Generators and Energy Storage Considering Thermal Power Deep Peak Clipping and Wind Energy Emission Grading Punishment
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作者 Junhui Li Xuanzhong Luo +2 位作者 Changxing Ge Cuiping Li Changrong Wang 《Energy Engineering》 EI 2024年第4期869-893,共25页
Peak load and wind energy emission pressure rise more as wind energy penetration keeps growing,which affects the stabilization of the PS(power system).This paper suggests integrated optimal dispatching of thermal powe... Peak load and wind energy emission pressure rise more as wind energy penetration keeps growing,which affects the stabilization of the PS(power system).This paper suggests integrated optimal dispatching of thermal power generators and BESS(battery energy storage system)taking wind energy emission grading punishment and deep peak clipping into consideration.Firstly,in order to minimize wind abandonment,a hierarchical wind abandonment penalty strategy based on fuzzy control is designed and introduced,and the optimal grid-connected power of wind energy is determined as a result of minimizing the peak cutting cost of the system.Secondly,considering BESS and thermal power,the management approach of BESS-assisted virtual peak clipping of thermal power generators is aimed at reducing the degree of deep peak clipping of thermal power generators and optimizing the output of thermal power generators and the charging and discharging power of BESS.Finally,Give an example of how this strategy has been effective in reducing abandonment rates by 0.66% and 7.46% individually for different wind penetration programs,and the daily average can reduce the peak clipping power output of thermal power generators by 42.97 and 72.31 MWh and enhances the effect and economy of system peak clipping. 展开更多
关键词 BESS wind energy deep peak clipping virtual peak clipping wind energy emission grading punishment
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Physics-informed machine learning model for prediction of ground reflected wave peak overpressure
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作者 Haoyu Zhang Yuxin Xu +1 位作者 Lihan Xiao Canjie Zhen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第11期119-133,共15页
The accurate prediction of peak overpressure of explosion shockwaves is significant in fields such as explosion hazard assessment and structural protection, where explosion shockwaves serve as typical destructive elem... The accurate prediction of peak overpressure of explosion shockwaves is significant in fields such as explosion hazard assessment and structural protection, where explosion shockwaves serve as typical destructive elements. Aiming at the problem of insufficient accuracy of the existing physical models for predicting the peak overpressure of ground reflected waves, two physics-informed machine learning models are constructed. The results demonstrate that the machine learning models, which incorporate physical information by predicting the deviation between the physical model and actual values and adding a physical loss term in the loss function, can accurately predict both the training and out-oftraining dataset. Compared to existing physical models, the average relative error in the predicted training domain is reduced from 17.459%-48.588% to 2%, and the proportion of average relative error less than 20% increased from 0% to 59.4% to more than 99%. In addition, the relative average error outside the prediction training set range is reduced from 14.496%-29.389% to 5%, and the proportion of relative average error less than 20% increased from 0% to 71.39% to more than 99%. The inclusion of a physical loss term enforcing monotonicity in the loss function effectively improves the extrapolation performance of machine learning. The findings of this study provide valuable reference for explosion hazard assessment and anti-explosion structural design in various fields. 展开更多
关键词 Blast shock wave peak overpressure Machine learning Physics-informed machine learning
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教育数字化背景下高职多模态PEAK教学模式设计与实施——以智能网联汽车技术课程为例
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作者 庄紫玮 《哈尔滨职业技术学院学报》 2024年第6期48-51,共4页
随着国家政策和社会需求的推动,教育数字化转型迫在眉睫。课堂是教育教学的主战场,教学是教育实践的根本途径。对教育数字化背景下多模态教学模式进行可行性分析后,构建适合高职教育的多模态PEAK教学模式,设计“三动三式”教学策略,实... 随着国家政策和社会需求的推动,教育数字化转型迫在眉睫。课堂是教育教学的主战场,教学是教育实践的根本途径。对教育数字化背景下多模态教学模式进行可行性分析后,构建适合高职教育的多模态PEAK教学模式,设计“三动三式”教学策略,实施“行动导向六贯穿”,创新“三维五星”联动评价体系,提供岗课融合、数字赋能的实施路径,促进数字技术与高职教育教学深度融合。 展开更多
关键词 教育数字化 多模态 peak教学模式 智能网联汽车技术
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Estimation of peak wave period from surface texture motion in videos
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作者 Haipeng Yu Xiaoliang Chu Guang Yuan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第9期136-144,共9页
Wave information retrieval from videos captured by a single camera has been increasingly applied in marine observation.However,when the camera observes ocean waves at low grazing angles,the accurate extraction of wave... Wave information retrieval from videos captured by a single camera has been increasingly applied in marine observation.However,when the camera observes ocean waves at low grazing angles,the accurate extraction of wave information from videos will be affected by the interference of the fine ripples on the sea surface.To solve this problem,this study develops a method for estimating peak wave periods from videos captured at low grazing angles.The method extracts the motion of the sea surface texture from the video and obtains the peak wave period via the spectral analysis.The calculation results captured from real-world videos are compared with those obtained from X-band radar inversion and tracking buoy movement,with maximum deviations of 8%and 14%,respectively.The analysis of the results shows that the peak wave period of the method has good stability.In addition,this paper uses a pinhole camera model to convert the displacement of the texture from pixel height to actual height and performs moving average filtering on the displacement of the texture,thus conducting a preliminary exploration of the inversion of significant wave height.This study helps to extend the application of sea surface videos. 展开更多
关键词 low grazing angle sea surface texture VIDEO peak wave period significant wave height image matching
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Peak Shaving Strategy of Concentrating Solar Power Generation Based on Multi-Time-Scale and Considering Demand Response
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作者 Lei Fang Haiying Dong +1 位作者 Xiaofei Zhen Shuaibing Li 《Energy Engineering》 EI 2024年第3期661-679,共19页
According to the multi-time-scale characteristics of power generation and demand-side response(DR)resources,as well as the improvement of prediction accuracy along with the approaching operating point,a rolling peak s... According to the multi-time-scale characteristics of power generation and demand-side response(DR)resources,as well as the improvement of prediction accuracy along with the approaching operating point,a rolling peak shaving optimization model consisting of three different time scales has been proposed.The proposed peak shaving optimization model considers not only the generation resources of two different response speeds but also the two different DR resources and determines each unit combination,generation power,and demand response strategy on different time scales so as to participate in the peaking of the power system by taking full advantage of the fast response characteristics of the concentrating solar power(CSP).At the same time,in order to improve the accuracy of the scheduling results,the combination of the day-ahead peak shaving phase with scenario-based stochastic programming can further reduce the influence of wind power prediction errors on scheduling results.The testing results have shown that by optimizing the allocation of scheduling resources in each phase,it can effectively reduce the number of starts and stops of thermal power units and improve the economic efficiency of system operation.The spinning reserve capacity is reduced,and the effectiveness of the peak shaving strategy is verified. 展开更多
关键词 peak shaving strategy concentrating solar power multi-time-scale demand-side response rolling optimization
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Assessment of Axial Power Peaking Factors in GHARR-1 LEU Core: A Decadal Simulation Analysis
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作者 Emmanuel Kwame Ahiave Emmanuel Ampomah-Amoako +1 位作者 Rex Gyeabour Abrefah Mathew Asamoah 《World Journal of Nuclear Science and Technology》 CAS 2024年第1期72-85,共14页
This study aims to thoroughly investigate the axial power peaking factors (PPF) within the low-enriched uranium (LEU) core of the Ghana Research Reactor-1 (GHARR-1). This study uses advanced simulation tools, like the... This study aims to thoroughly investigate the axial power peaking factors (PPF) within the low-enriched uranium (LEU) core of the Ghana Research Reactor-1 (GHARR-1). This study uses advanced simulation tools, like the MCNPX code for analysing neutron behavior and the PARET/ANL code for understanding power variations, to get a clearer picture of the reactor’s performance. The analysis covers the initial six years of GHARR-1’s operation and includes projections for its whole 60-year lifespan. We closely observed the patterns of both the highest and average PPFs at 21 axial nodes, with measurements taken every ten years. The findings of this study reveal important patterns in power distribution within the core, which are essential for improving the safety regulations and fuel management techniques of the reactor. We provide a meticulous approach, extensive data, and an analysis of the findings, highlighting the significance of continuous monitoring and analysis for proactive management of nuclear reactors. The findings of this study not only enhance our comprehension of nuclear reactor safety but also carry significant ramifications for sustainable energy progress in Ghana and the wider global context. Nuclear engineering is essential in tackling global concerns, such as the demand for clean and dependable energy sources. Research on optimising nuclear reactors, particularly in terms of safety and efficiency, is crucial for the ongoing advancement and acceptance of nuclear energy. 展开更多
关键词 GHARR-1 Power peaking Factor Nuclear Reactor Safety Low Enriched Uranium Core Operational Longevity Thermal Hydraulics
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Peak Particle Velocity Predicting Equation Associated with the Propagation of Vibrations Induced by Blasting in a Mine and Impacts on the Physical Degradation of Houses: The Case of the Yaramoko Mine, Bagassi, Burkina Faso
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作者 Richard Zoundi Antoine Béré +1 位作者 Joel Martial Balkoulga Philibert Sawadogo 《Journal of Minerals and Materials Characterization and Engineering》 2024年第6期316-333,共18页
This study utilizes empirical equations to describe the propagation of vibrations induced by blasting, with the goal of predicting the attenuation of Peak Particle Velocity (PPV) at the Yaramoko mine in Bagassi, Burki... This study utilizes empirical equations to describe the propagation of vibrations induced by blasting, with the goal of predicting the attenuation of Peak Particle Velocity (PPV) at the Yaramoko mine in Bagassi, Burkina Faso, a site characterized by granitoid rock. Four empirical PPV prediction equations were employed, so-called Duvall & Fogelson (or the United States Bureau of Mines “USBM”), Langefors and Kihlstrom, Ambressys-Hendron, and the Bureau of Indian Standard. The constant parameters for each of these equations, referred to as site constants, were derived from linear regression curves. The results show that the site constants k, a, and b of 4762, 0.869, and 1.737, respectively, derived from the general prediction equation by Davies, PPV = kQaD−b, based on Duvall & Fogelson, are in good agreement with values of 4690, 0.9, and 1.69, respectively, for similar rock types in Spain. Regarding the impacts of blasting on houses, the findings indicate that houses built from laterite-block bricks in the village of Bagassi are the most vulnerable to vibration waves, followed by those constructed with cinder-block bricks. In contrast, houses made of banco bricks are the most resilient. Additionally, it was determined that during blasting operations, adjusting the blasting parameters to ensure the PPV does not exceed 2 mm/s at the level of nearby dwellings can minimize the appearance of cracks in houses. 展开更多
关键词 peak Particle Velocity BLASTING Propagation of Blasting Vibrations Cracks on Houses PPV Equation
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Spatiotemporal variations of ecosystem services and driving factors in the Tianchi Bogda Peak Natural Reserve of Xinjiang,China
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作者 ZHU Haiqiang WANG Jinlong +2 位作者 TANG Junhu DING Zhaolong GONG Lu 《Journal of Arid Land》 SCIE CSCD 2024年第6期816-833,共18页
Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,i... Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,is an important ecological barrier area in the temperate arid zone.The evaluation of its important ecosystem services is of great significance to improve the management level and ecological protection efficiency of the reserve.In the present study,we assessed the spatiotemporal variations of four ecosystem services(including net primary productivity(NPP),water yield,soil conservation,and habitat quality)in the TBPNR from 2000 to 2020 based on the environmental and social data using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.In addition,the coldspot and hotspot areas of ecosystem services were identified by hotspot analysis,and the trade-off and synergistic relationships between ecosystem services were analyzed using factor analysis in a geographic detector.During the study period,NPP and soil conservation values in the reserve increased by 48.20%and 25.56%,respectively;conversely,water yield decreased by 16.56%,and there was no significant change in habitat quality.Spatially,both NPP and habitat quality values were higher in the northern part and lower in the southern part,whereas water yield showed an opposite trend.Correlation analysis revealed that NPP showed a synergistic relationship with habitat quality and soil conservation,and exhibited a trade-off relationship with water yield.Water yield and habitat quality also had a trade-off relationship.NPP and habitat quality were affected by annual average temperature and Normalized Difference Vegetation Index(NDVI),respectively,while water yield and soil conservation were more affected by digital elevation model(DEM).Therefore,attention should be paid to the spatial distribution and dynamics of trade-off and synergistic relationships between ecosystem services in future ecological management.The findings of the present study provide a reference that could facilitate the sustainable utilization of ecosystem services in the typical fragile areas of Northwest China. 展开更多
关键词 net primary productivity(NPP) water yield soil conservation habitat quality Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model geographic detector Tianchi Bogda peak Natural Reserve
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多情景视角下丝绸之路经济带沿线省份碳达峰预测
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作者 张朝辉 张靖雅 于师琪 《生态经济》 北大核心 2025年第1期80-88,共9页
基于碳达峰碳中和目标的战略背景,结合“共建绿色丝绸之路”的时代倡议,考虑丝绸之路经济带国内沿线省份的产业发展态势,运用STIRPAT拓展模型,构建碳排放量与各影响因素的预测模型,进一步设置不同情景模式,预测丝绸之路经济带沿线省份2... 基于碳达峰碳中和目标的战略背景,结合“共建绿色丝绸之路”的时代倡议,考虑丝绸之路经济带国内沿线省份的产业发展态势,运用STIRPAT拓展模型,构建碳排放量与各影响因素的预测模型,进一步设置不同情景模式,预测丝绸之路经济带沿线省份2021—2040年的碳达峰趋势。结果表明:(1)能源消耗水平对碳排放的影响最大,是影响丝绸之路经济带沿线省份碳达峰的最重要因素。(2)技术突破模式下,丝绸之路经济带沿线省份在2030年实现碳达峰,峰值4808.43×106吨;政策调控和数字经济模式下,丝绸之路经济带沿线省份在2035年实现碳达峰,峰值分别为5519.46×106吨和4988.32×106吨;基准模式下,丝绸之路经济带沿线省份未能实现碳达峰。(3)内蒙古、陕西和新疆是碳达峰重点关注区,应加快政策落地、加大技术突破、加强数字经济,确保如期实现碳达峰。 展开更多
关键词 绿色丝绸之路经济带 技术突破 数字经济 碳达峰 情景预测
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长直坑道内爆炸冲击波相似规律研究
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作者 王新颖 秦毅 +1 位作者 赵涯 綦鸿力 《沈阳理工大学学报》 CAS 2025年第1期65-71,共7页
通过长直坑道内炸药爆炸后冲击波的超压峰值变化研究坑道内爆炸冲击波的相似规律。使用AUTODYN软件建立长直坑道仿真模型,采用映射方法将3.25 kg当量的球形TNT炸药在空气中的爆炸状态映射到长直坑道中,采用经典试验结果对模型进行验证... 通过长直坑道内炸药爆炸后冲击波的超压峰值变化研究坑道内爆炸冲击波的相似规律。使用AUTODYN软件建立长直坑道仿真模型,采用映射方法将3.25 kg当量的球形TNT炸药在空气中的爆炸状态映射到长直坑道中,采用经典试验结果对模型进行验证。根据几何相似原理,通过改变坑道尺寸、坑道截面形状、炸点位置和炸药当量建立多组不同的模型,模拟计算得到坑道内爆炸冲击波的超压峰值,分析超压峰值的相似规律。结果表明,保持坑道截面积不变、改变截面形状及保持爆心距与炸药当量的比值不变、改变炸药当量,各模型计算得到的冲击波超压峰值具有相似规律。采用本文方法可对其他满足几何相似原理的坑道内爆炸冲击波参数进行预测,为地下空间设施的安全设计提供参考。 展开更多
关键词 长直坑道 冲击波 超压峰值 相似规律
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Chopping-peaking开关形成高功率超宽带双极脉冲的实验研究 被引量:12
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作者 樊亚军 石磊 +4 位作者 刘国治 汪文秉 周金山 刘峰 朱郁丰 《强激光与粒子束》 EI CAS CSCD 北大核心 2004年第4期501-504,共4页
 设计研制了一种chopping peaking组合开关型高功率双极脉冲形成装置,通过调节两个开关的导通时刻来得到不同形状的双极脉冲。理想情况下,形成的双极脉冲电压峰 峰值等于入射脉冲峰值电压的2倍,实验中入射脉冲峰值电压为205kV的单极脉...  设计研制了一种chopping peaking组合开关型高功率双极脉冲形成装置,通过调节两个开关的导通时刻来得到不同形状的双极脉冲。理想情况下,形成的双极脉冲电压峰 峰值等于入射脉冲峰值电压的2倍,实验中入射脉冲峰值电压为205kV的单极脉冲,获得了最大峰 峰电压为360kV的双极脉冲,是入射脉冲峰值电压的1.76倍。双极脉冲的持续时间可以改变,最大值为单极脉冲的脉宽。入射脉冲上升时间越小,得到的双极脉冲峰 峰电压就越大。 展开更多
关键词 超宽带 双极脉冲 陡化 chopping开关 peaking开关
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O_2 peak:释义与应用 被引量:9
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作者 张建国 施启蓉 张雪琴 《体育科学》 CSSCI 北大核心 2007年第7期80-85,共6页
O2 peak常用于评价不同人群有氧工作能力,是近年来国外运动医学文献中出现频度较高的一个专业术语。就O2 peak这一术语的解释、与O2 max的区别、应用范围以及再测信度进行了综述。尽管学者们对.O2 peak有着不同的解释,但是,O2... O2 peak常用于评价不同人群有氧工作能力,是近年来国外运动医学文献中出现频度较高的一个专业术语。就O2 peak这一术语的解释、与O2 max的区别、应用范围以及再测信度进行了综述。尽管学者们对.O2 peak有着不同的解释,但是,O2 peak在研究对象、判断标准、运动负荷方法等方面与.O2 max存在明显的差异。O2 peak常用于不同人群的流行病学研究,具有较高的实用性。许多研究表明,O2 peak有很高的再测信度,是一项稳定性较好的测试指标。 展开更多
关键词 VO2 peak VO2MAX 术语解释 应用范围
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Quantitative prediction of channel sand bodies based on seismic peak attributes in the frequency domain and its application 被引量:2
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作者 孙鲁平 郑晓东 +2 位作者 首皓 李劲松 李艳东 《Applied Geophysics》 SCIE CSCD 2010年第1期10-17,98,共9页
The boundary identification and quantitative thickness prediction of channel sand bodies are always difficult in seismic exploration.We present a new method for boundary identification and quantitative thickness predi... The boundary identification and quantitative thickness prediction of channel sand bodies are always difficult in seismic exploration.We present a new method for boundary identification and quantitative thickness prediction of channel sand bodies based on seismic peak attributes in the frequency domain.Using seismic forward modeling of a typical thin channel sand body,a new seismic attribute-the ratio of peak frequency to amplitude was constructed.Theoretical study demonstrated that seismic peak frequency is sensitive to the thickness of the channel sand bodies,while the amplitude attribute is sensitive to the strata lithology.The ratio of the two attributes can highlight the boundaries of the channel sand body.Moreover,the thickness of the thin channel sand bodies can be determined using the relationship between seismic peak frequency and thin layer thickness.Practical applications have demonstrated that the seismic peak frequency attribute can depict the horizontal distribution characteristics of channels very well.The ratio of peak frequency to amplitude attribute can improve the identification ability of channel sand body boundaries.Quantitative prediction and boundary identification of channel sand bodies with seismic peak attributes in the frequency domain are feasible. 展开更多
关键词 channel sand bodies seismic peak frequency attribute seismic peak amplitude attribute boundary identification quantitative prediction
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Overlapped peaks resolution for linear sweep polarography using Gaussian-like distribution 被引量:2
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作者 朱红求 王国伟 +2 位作者 阳春华 曹宇 桂卫华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2181-2186,共6页
A resolution method based on Gaussian-like distribution for overlapped linear sweep polarographic peaks was proposed to simultaneously detect the polymetallic components, such as Zn(Ⅱ) and Co(Ⅱ), coexisting in t... A resolution method based on Gaussian-like distribution for overlapped linear sweep polarographic peaks was proposed to simultaneously detect the polymetallic components, such as Zn(Ⅱ) and Co(Ⅱ), coexisting in the leaching solution of zinc hydrometallurgy. A Gaussian-like distribution was constructed as the sub-model of overlapped peaks by analyzing the characteristics of linear sweep polarographic curve. Then, the abscissas of each peak and trough were pinpointed through multi-resolution wavelet decomposition, the curve and its derivative curves were fitted by using nonlinear weighted least squares (NWLS). Finally, overlapped peaks were resolved into independent sub-peaks based on fitted reconstruction parameters. The experimental results show that the relative error of half-wave potential pinpointed by multi-resolution wavelet decomposition is less than 1% and the accuracy of Ip fitted by NWLS is higher than 96%. The proposed resolution method is effective for overlapped linear sweep polarographic peaks of Zn(Ⅱ) and Co(Ⅱ). 展开更多
关键词 zinc hydrometallurgy Gaussian-like distribution overlapped peaks resolution multi-resolution wavelet decomposition nonlinear weighted least squares fitting
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不同耐力跑测试评价VO_(2max)/VO_(2peak)效度的比较研究 被引量:2
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作者 马相华 曹振波 +2 位作者 朱政 赵胜 李红果 《中国体育科技》 CSSCI 北大核心 2021年第10期70-78,共9页
目的:梳理采用不同耐力跑测试[800 m跑、805 m跑、1500 m跑、1609 m跑、12 min跑、20 m往返跑(20 m SRT)]评价健康人群VO_(2max)/VO_(2peak)的效度研究,系统比较不同测试方法的效度差异。方法:检索了LISTA(EBSCO)、PubMed(NLM)、Web of ... 目的:梳理采用不同耐力跑测试[800 m跑、805 m跑、1500 m跑、1609 m跑、12 min跑、20 m往返跑(20 m SRT)]评价健康人群VO_(2max)/VO_(2peak)的效度研究,系统比较不同测试方法的效度差异。方法:检索了LISTA(EBSCO)、PubMed(NLM)、Web of Science(TS)与中国知网(CNKI)数据库,采用Castro-Piňero的文献质量评价标准对纳入文献进行质量评价(Ross et al.,2016)。结果:800 m、805 m、1000 m跑时间与VO_(2max)/VO_(2peak)的相关系数(r):男性儿童青少年为-0.224~-0.781,女性为-0.495~-0.697;男性成年人群为-0.219~-0.736,女性为-0.139~-0.626。1500 m、1609 m跑时间与VO_(2max)/VO_(2peak)的r值:儿童、青少年为-0.603~-0.790;成年人群为-0.627~-0.729。12 min跑距离与VO_(2max)/VO_(2peak)r值:青少年儿童0.977(男)、0.964(女);成年人群为0.730~0.897,预测方程的R值为0.87,0.872(男)、0.862(女)。20 m SRT预测方程值与直接测量VO_(2max)的r值:青少年儿童为0.60~0.90,决定系数(R2)为0.46~0.81,标准误(SEE)为3.33~7.26 ml·kg^(-1)·min^(-1);成年人群为0.43~0.94,R2为0.87~0.88,SEE为1.38~3.00 ml·kg^(-1)·min^(-1)。结论:作为有氧能力(VO_(2max)/VO_(2peak))的间接评价方法,800 m、805 m、1000 m跑效度最低,波动幅度大;1500 m、1609 m跑效度较高,适用人群广泛;12 min跑、20 m SRT效度最高,并且效度稳定。在实际应用中,应根据研究目的、监测人群合理选择,谨慎解读其监测结果。针对我国人群的耐力跑评测有氧能力(VO_(2max)/VO_(2peak))效度的研究有待进一步开展。 展开更多
关键词 有氧能力 耐力跑 评价 测试 VO_(2max) VO_(2peak) 效度
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465名正常成人QT peak离散度研究 被引量:5
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作者 王慕璇 蔡晓英 +2 位作者 朱维琪 李丽 周晓澜 《新医学》 北大核心 2001年第2期80-81,共2页
目的:探讨正常成人QTpeak离散度(QTpd)的正常范围及不同测量者之间的测量误差。方法:对465名正常成人以25mm/s纸速记录常规12导联同步心电图。测量QTpd及QTd并比较不同测量者之间QTpd的测量误差。结果:最小QTpeak79%出现于V2导联,最大QT... 目的:探讨正常成人QTpeak离散度(QTpd)的正常范围及不同测量者之间的测量误差。方法:对465名正常成人以25mm/s纸速记录常规12导联同步心电图。测量QTpd及QTd并比较不同测量者之间QTpd的测量误差。结果:最小QTpeak79%出现于V2导联,最大QTpeak43%出现于V6导联、37%出现于aVF导联。465名正常成人QTpd为10ms~55ms(30±10)ms,不同测量者之间测量结果差异无显著性,QTpd与QTd结果的相关性好。结论:465名正常成人QTpd为10ms~55ms(30±10)ms。12导联同步心电图测量QTpd具有简单、准确的优点。 展开更多
关键词 心电锚记术 Q-T间期 QTpeak间期 QTpeak离散度 QT离散度
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吸气肌力量训练对大学生VO_2peak的影响 被引量:4
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作者 赵敬国 朱同乐 曹丽凤 《生物医学工程研究》 2010年第1期18-22,共5页
探讨吸气肌力量训练是否会影响以主观感觉为主要判定标准的VO2peak值。观察了为期4周的吸气肌力量训练(训练负荷为80%MIP,30次/30分/天,5天/周,共20个训练周期)过程中VO2peak值及运动能力的动态改变。VO2peak测定采用德国耶格公司生产的... 探讨吸气肌力量训练是否会影响以主观感觉为主要判定标准的VO2peak值。观察了为期4周的吸气肌力量训练(训练负荷为80%MIP,30次/30分/天,5天/周,共20个训练周期)过程中VO2peak值及运动能力的动态改变。VO2peak测定采用德国耶格公司生产的MasterScreen CPX运动肺功能仪。随吸气肌训练周期的延长,吸气肌力量、GXT运动持续时间及完成的最大负荷值以及VO2peak的绝对值和相对值均呈显著性意义的增加(P<0.01),但RPE值则没有显著性意义的改变(P>0.05);而对照组则没有显著性意义的改变(P>0.05)。说明4周吸气肌力量训练可显著性提高以主观感觉为主要判定标准的VO2peak值以及递增负荷运动试验(GXT)的运动能力。 展开更多
关键词 VO2peak 吸气肌训练 运动能力 递增负荷运动试验(GXT) 吸气肌力量
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吸气肌训练对健康大学生VO_2peak、肺功能及运动能力的影响 被引量:3
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作者 赵敬国 朱同乐 曹丽凤 《吉林体育学院学报》 2010年第3期62-64,共3页
探讨呼吸肌训练能否影响以主观感觉为主要判定标准的VO2peak值以及肺功能和运动能力。方法:观察了为期4周的吸气肌力量训练过程中VO2peak值、肺功能及运动能力的动态改变。结果:随吸气肌训练周期的延长,吸气肌力量、GXT运动持续时间及... 探讨呼吸肌训练能否影响以主观感觉为主要判定标准的VO2peak值以及肺功能和运动能力。方法:观察了为期4周的吸气肌力量训练过程中VO2peak值、肺功能及运动能力的动态改变。结果:随吸气肌训练周期的延长,吸气肌力量、GXT运动持续时间及完成的最大负荷值以及VO2peak的绝对值和相对值均呈显著性意义的增加(P<0.01);而对照组则没有显著性意义的改变(P>0.05)。MV、VCmax和FEV1均没有显著性意义的差异(P>0.05)。结论:4周吸气肌力量训练可显著性提高以主观感觉为主要判定标准的VO2peak值以及递增负荷运动试验(GXT)的运动能力。 展开更多
关键词 VO2peak 吸气肌训练 运动能力 递增负荷运动试验(GXT) 肺功能
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A Low-Power High-Frequency CMOS Peak Detector
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作者 李学初 高清运 秦世才 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第10期1707-1710,共4页
A low-power,high-frequency CMOS peak detector is proposed. This detector can detect RF signal and base-band signal peaks. The circuit is designed using SMIC 0.35μm standard CMOS technology. Both theoretical calculati... A low-power,high-frequency CMOS peak detector is proposed. This detector can detect RF signal and base-band signal peaks. The circuit is designed using SMIC 0.35μm standard CMOS technology. Both theoretical calculations and post simulations show that the detection error is no more than 2% for various temperatures and processes when the input amplitude is larger than 400mV. The detection bandwidth is up to 10GHz, and its static current dissipation is less than 20μA. 展开更多
关键词 CMOS peak detector lower power high frequency
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