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随机森林在低轨空间目标阻力系数确定问题中的应用

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测绘地理信息 2024年第2期49卷 33-37页

作者：刘涵月夏胜夫桑吉章武汉大学测绘学院湖北武汉430079 地球空间信息技术协同创新中心湖北武汉430079

对绝大多数空间目标而言,由于观测条件和观测手段的限制,测轨数据稀疏且精度较低,传统轨道确定时一并解算的大气阻力系数精度稳定性很差。针对这一问题,提出一种基于随机森林的大气阻力系数预测模型。该模型主要利用某个目标的历史大气... 详细信息

对绝大多数空间目标而言,由于观测条件和观测手段的限制,测轨数据稀疏且精度较低,传统轨道确定时一并解算的大气阻力系数精度稳定性很差。针对这一问题,提出一种基于随机森林的大气阻力系数预测模型。该模型主要利用某个目标的历史大气阻力系数、轨道数据、太阳地磁指数、大气密度等信息预测该目标未来一段时间内的大气阻力系数。仿真GRACE(gravity recovery and climate experiment)A卫星2002年的测轨数据,进行多个时间段的轨道确定与预报模拟实验。结果表明,相比于传统方法,利用所提模型预测大气阻力系数,再将其应用于轨道确定和预报,7天轨道预报最大误差降幅可达60%,有效抑制了最大误差,为稀疏测轨数据条件下改善空间目标轨道确定与预报精度提供了一种技术途径。

关键词：大气阻力系数轨道预报随机森林稀疏数据

VEX VRC机器人竞赛设备软硬件优化的研究

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自动化应用 2024年第3期65卷 47-50页

作者：苏际恺郑敏晔刘涵月福建师范大学附属中学福建福州350007

为进一步提高参加VEX VRC机器人竞赛设备的质量,首先,从硬件结构的选择及优化角度,深入研究了机器人底盘设计、得分机制以及飞盘发射结构的关键因素,考虑了底盘高度、轮胎选择、得分结构的动力和驱动方式、飞轮和弹弓结构的优缺点等;其... 详细信息

为进一步提高参加VEX VRC机器人竞赛设备的质量,首先,从硬件结构的选择及优化角度,深入研究了机器人底盘设计、得分机制以及飞盘发射结构的关键因素,考虑了底盘高度、轮胎选择、得分结构的动力和驱动方式、飞轮和弹弓结构的优缺点等;其次,详细描述了基于PID程序框架的调整优化方法,包括PID控制的基本原理、优化策略、多角度PID控制的应对策略以及响应速度与精度的权衡;最后,还针对设备剧烈震动和转弯策略进行了具体的应用调整,以确保机器人的高效稳定运行。

关键词： VEX VRC机器人竞赛 PID控制底盘设计

Toward inclusive list-making for trade liberalization in environmental goods to reduce carbon emissions

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Geography and Sustainability 2023年第3期4卷 200-212页

作者： Xiyan Mao hanyue liu Jingxuan Gui Peiyu Wang School of Geography and Ocean Science Nanjing UniversityNanjing 210023China

The Asia-Pacific Economic Cooperation(APEC)is contemplating expanding its list of environmental goods(EG)for trade liberalization to fight climate *** support of doing so,this study proposes that a long list that retains controversies is better for carbon emission reduction than a short common *** study examines four mechanisms of longer lists:enlarging market scales,enriching product mixes,enhancing product sophistication,and enriching trade *** China’s emerging EG trade during the 2001-2015 period as a case study,this study compares four EG lists with different *** results show that:(1)a longer list reduces carbon emissions from both imports and exports,making domestic regions with different advantages have better chances of improving carbon efficiencies.(2)Product sophistication reduces the emission gap between trading partners,regardless of the length of EG lists.(3)China’s EG exports contribute to carbon reduction in leading regions,while EG imports provide laggard regions with better chances of reducing carbon *** findings provide three implications for future list-making:it is important to(1)seek a long and inclusive list rather than a short common list,(2)shift the focus from environmental end-use to the technological contents of products,and(3)balance the demand of laggard regions to import and the capacity of leading regions to export.

关键词： Carbon emissions Global environmental governance Environmental goods Inequality Product sophistication

Attention-based neural network for end-to-end music separation

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CAAI Transactions on Intelligence Technology 2023年第2期8卷 355-363页

作者： Jing Wang hanyue liu Haorong Ying Chuhan Qiu Jingxin Li Muhammad Shahid Anwar Beijing Institute of Technology BeijingChina Communication University of China BeijingChina China Electronics Standardization Institute BeijingChina Gachon University SeongnamSouth Korea

The end-to-end separation algorithm with superior performance in the field of speech separation has not been effectively used in music ***,since music signals are often dual channel data with a high sampling rate,how to model longsequence data and make rational use of the relevant information between channels is also an urgent problem to be *** order to solve the above problems,the performance of the end-to-end music separation algorithm is enhanced by improving the network *** main contributions include the following:(1)A more reasonable densely connected U-Net is designed to capture the long-term characteristics of music,such as main melody,tone and so on.(2)On this basis,the multi-head attention and dualpath transformer are introduced in the separation *** attention units are applied recursively on the feature map of each layer of the network,enabling the network to perform long-sequence *** results show that after the introduction of the channel attention,the performance of the proposed algorithm has a stable improvement compared with the baseline *** the MUSDB18 dataset,the average score of the separated audio exceeds that of the current best-performing music separation algorithm based on the time-frequency domain(T-F domain).

关键词： channel attention densely connected network end-to-end music separation

Blood glucose-lowering activity of protocatechuic acid is mediated by inhibiting a-glucosidase

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Food Science and Human Wellness 2024年第3期13卷 1212-1219页

作者： Huafang Ding Shouhe Huang Chui Yiu Chook Erika Kwek Chi Yan Kaying Ma Jianhui liu hanyue Zhu Zhenyu Chen Food&Nutritional Sciences Programme School of Life SciencesThe Chinese University of Hong KongHong Kong 999077China

α-Glucosidase inhibitors are effective in controlling postprandial hyperglycemia,which play crucial roles in the management of type 2 *** acid(PCA)is one of phenolic acids existing not only in various plant foods but also as a major microbial metabolite of dietary anthocyanins in the large *** present study investigated the inhibitory mechanism of PCA on a-glucosidase in vitro and examined its effect on postprandial blood glucose levels in *** from in vitro experiments demonstrated that PCA was a mix-type inhibitor of *** by hydrogen bonds and van der Waals interactions,PCA reversibly bound withα-glucosidase to form a stable a-glucosidase-PCA complex in a spontaneous *** computational simulation found that PCA could insert into the active cavity of a-glucosidase and establish hydrogen bonds with catalytic amino acid *** binding aroused the steric hindrance for substrates to enter active sites and caused the structural changes of interacted catalytic amino acid *** also exhibited postprandial hypoglycemic capacity in diabetic *** study may provide the theoretical basis for the application of PCA as an active ingredient of functional foods in dietary management of diabetes.

关键词： Protocatechuic acid α-Glucosidase Postprandial hyperglycemia Inhibition mechanism

Dynamic risk assessment of gas pipeline operation process by fusing visual and olfactory monitoring

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Journal of Safety Science and Resilience 2024年第2期5卷 156-166页

作者： Denglong Ma Weigao Mao Guangsen Zhang Chaoyi liu Yi Han Xiaoming Zhang Hansheng Wang Kang Cen Wan Lu Denghui Li hanyue Zhang School of Mechanical Engineering Xi'an Jiaotong UniversityXi'an 710049China Hanzhong Natural Gas Investinent Development Co.Ltd Hanzhong723011China Shaanxi Special Equipment Inspection and Testing Institute Xi'an710038China School of Civil Engineering and Architecture Southwest Petroleum UniversityChengdu610500China Sichuan Tianxin Gas Co.Ltd. Mianyang62100China Petro China Southwest Oil and Gas Field Company Gas Branch Chengdu610500China

With the rapid increase in urban gas consumption,the frequency of maintenance and repair of gas pipelines has escalated,leading to a rise in safety accidents during these *** traditional manual supervision model presents challenges such as inaccurate monitoring results,incomplete risk factor analysis,and a lack of quantitative risk *** research focuses on developing a dynamic risk assessment technology for gas emergency repair operations by integrating the monitoring outcomes of artificial olfactory for gas leakage information and video object recognition for visual safety factor monitoring *** quantitatively evaluate the risk of the operation process,a three-dimensional risk assessment model combining gas leakage with riskcorrelated sensitivity was established as well as a separate three-dimensional risk assessment model integrating visual risk factors with predictable risk ***,a visual risk quantification expression mode based on the risk matrix-radar map method was ***,a risk quantification model based on the fusion of visual and olfactory results was *** verification results of simulation scenarios based on field data indicate that the visual-olfactory fusion risk assessment method can more accurately reflect the dynamic risk level of the operation process compared to simple visual safety factor *** outcomes of this research can contribute to the identification of safety status and early warning of risks related to personnel,equipment,and environmental factors in emergency repair ***,these results can be extended to other operational scenarios,such as oil and gas production stations and long-distance pipeline operations.

关键词： Gas pipelinemaintenance Dynamicriskassessment Visual-olfactoryfusion Risk matrix Risk quantification model

A unique subseafloor microbiosphere in the Mariana Trench driven by episodic sedimentation

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Marine Life Science & Technology 2024年第1期6卷 168-181页

作者： Jiwen liu Da-Wei Li Xinxin He Ronghua liu Haojin Cheng Chenglong Su Mengna Chen Yonghong Wang Zhongsheng Zhao hanyue Xu Zhangyu Cheng Zicheng Wang Nikolai Pedentchouk David J.Lea-Smith Jonathan D.Todd Xiaoshou liu Meixun Zhao Xiao-Hua Zhang Frontiers Science Center for Deep Ocean Multispheres and Earth System and College of Marine Life SciencesOcean University of ChinaQingdao 266003China Laboratory for Marine Ecology and Environmental Science Laoshan LaboratoryQingdao 266237China Institute of Evolution and Marine Biodiversity Ocean University of ChinaQingdao 266003China Key Laboratory of Marine Chemistry Theory and Technology Ministry of EducationOcean University of ChinaQingdao 266100China Key Lab of Submarine Geosciences and Prospecting Techniques Ministry of Education/College of Marine GeosciencesOcean University of ChinaQingdao 266100China Key Laboratory of Physical Oceanography Ministry of Education/Research Vessel CentreOcean University of ChinaQingdao 266100China School of Environmental Sciences University of East AngliaNorwich NR47TJUK School of Biological Sciences University of East AngliaNorwich NR47TJUK

Hadal trenches are characterized by enhanced and infrequent high-rate episodic sedimentation events that likely introduce not only labile organic carbon and key nutrients but also new microbes that significantly alter the subseafloor ***,the role of high-rate episodic sedimentation in controlling the composition of the hadal subseafloor microbiosphere is ***,analyses of carbon isotope composition in a~750 cm long sediment core from the Challenger Deep revealed noncontinuous deposition,with anomalous ^(14)C ages likely caused by seismically driven mass transport and the funneling effect of trench *** community composition and diverse enzyme activities in the upper~27 cm differed from those at lower depths,probably due to sudden sediment deposition and differences in redox condition and organic matter *** lower depths,microbial population numbers,and composition remained relatively constant,except at some discrete depths with altered enzyme activity and microbial phyla abundance,possibly due to additional sudden sedimentation events of different *** is provided of a unique role for high-rate episodic sedimentation events in controlling the subsurface microbiosphere in Earth’s deepest ocean floor and highlight the need to perform thorough analysis over a large depth range to characterize hadal benthic *** depositional processes are likely crucial in shaping deep-water geochemical environments and thereby the deep subseafloor biosphere.

关键词： Hadal subseafloor Deep water sediment Mariana Trench Radiocarbon Microbial community Redox potential

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论思想政治教育图像话语的三重功能

北京教育学院学报 2023年第6期37卷 36-43页

作者：刘光斌刘含玥湖南大学马克思主义学院湖南长沙410082

图像话语作为一种重要的思想政治教育话语形式,在思想政治教育中发挥着三种重要功能:一是陈述功能,即思想政治教育图像话语出于社会实践目的陈述与社会生活相关的各种要素,包括形式陈述功能、情境陈述功能与历史陈述功能;二是指涉功能,... 详细信息

图像话语作为一种重要的思想政治教育话语形式,在思想政治教育中发挥着三种重要功能:一是陈述功能,即思想政治教育图像话语出于社会实践目的陈述与社会生活相关的各种要素,包括形式陈述功能、情境陈述功能与历史陈述功能;二是指涉功能,即思想政治教育图像话语指涉超出其表层语义的其他深层含义,包括现实指涉功能、象征指涉功能与感性指涉功能;三是建构功能,即思想政治教育图像话语有目的地建构社会存在和社会关系,包括精神文明建构功能、意识形态建构功能与规则秩序建构功能。正确认识思想政治教育图像话语的三重功能,对于促进思想政治教育图像话语在教学实践中的合理运用、提高新时代思想政治教育的科学性和实效性具有重要意义。

关键词：思想政治教育图像话语图像话语

腔内超声在直肠间质瘤诊断及新辅助治疗疗效评估中的应用价值

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现代肿瘤医学 2022年第4期30卷 697-700页

作者：刘寒月郑渤陈月新石刚葫芦岛市中心医院功能科辽宁葫芦岛125001 中国医科大学肿瘤医院辽宁省肿瘤医院结直肠外科辽宁沈阳110042

目的:评价腔内超声在直肠间质瘤诊断及新辅助治疗疗效评估中的应用价值,为直肠间质瘤临床诊断及疗效评估提供客观依据。方法:回顾性分析2015年05月至2020年05月我院46例直肠黏膜下肿瘤经直肠腔内超声进行鉴别诊断的患者,与病理诊断直肠... 详细信息

目的:评价腔内超声在直肠间质瘤诊断及新辅助治疗疗效评估中的应用价值,为直肠间质瘤临床诊断及疗效评估提供客观依据。方法:回顾性分析2015年05月至2020年05月我院46例直肠黏膜下肿瘤经直肠腔内超声进行鉴别诊断的患者,与病理诊断直肠间质瘤作为金标准进行直肠腔内超声诊断效能的验证。观察17例直肠间质瘤腔内超声参数,评价腔内超声对伊马替尼新辅助治疗的疗效评估价值,观察病理危险度与超声参数的关系。结果:直肠腔内超声诊断与病理诊断符合率为89.13%,灵敏度为88.24%,特异度为89.66%;直肠腔内超声显示,17例直肠间质瘤患者中,52.94%的肿瘤直径大于5 cm,76.47%的肿瘤为低回声,88.24%的肿瘤未发生囊性变,76.47%的肿瘤血运丰富,64.71%的肿瘤为向腔内生长型;直肠腔内超声对14例新辅助治疗患者进行评价,部分缓解57.14%(8/14),稳定42.86%(6/14),与治疗前比较,肿瘤直径减小(P<0.01),回声降低(P<0.05),囊性变增加(P<0.05),血流丰富程度降低(P<0.01)。肿瘤直径大,危险度高(P<0.01),肿瘤血运丰富,危险度高(P<0.05)。结论:直肠腔内超声在直肠间质瘤诊断中具有较高的灵敏度及特异度,可用于直肠间质瘤的鉴别诊断及新辅助治疗的疗效评估。

关键词：直肠间质瘤直肠腔内超声甲磺酸伊马替尼片