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Journal of Bionic Engineering 2020年第4期17卷 780-792页

作者： Liming wu Xiaomin Liu menghao Wang Department of Fluid Machinery and Engineering School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an 710049China The 705 Research Institute China State Shipbuilding Corporation LimitedXi'an 710077China

The aerodynamic noise generated by the centrifugal fan used in the air conditioner is related to the comfort of human living and working,which can be controlled by using the bionic design and optimization of key components of centrifugal *** by the non-smooth leading edge of long-eared owl wing,eight kinds of volute tongues are proposed to reduce the aerodynamic noise of a centrifugal *** flow and sound characteristics are numerically investigated by incorporating computational fluid dynamics and computational *** optimal result exhibits a noise reduction of up to 1.5 dB with a slight increase in mass flow *** acoustic characteristics,with respect to the sound pressure level,power spectral density,and sound directivity are *** time-domain,frequency-domain,and root mean square values of pressure fluctuation are monitored and analyzed to assess the unsteady flow interaction between the volute tongue and *** intensity and scale of vortices in the centrifugal fan are suppressed in the upstream and downstream of the bionic volute tongue,and the turbulence effect on the surface of the volute tongue becomes even and weak.

关键词： bionic design volute tongue centrifugal fan noise reduction numerical simulation

脑出血开颅手术泵注右美托咪定预防术后呛咳的效果观察

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现代养生 2020年第Z5期20卷 52-54页

作者：管朝勇吴梦淏苗振华河北省邢台市第三医院手麻科

目的探讨脑出血开颅手术泵注右美托咪定预防术后呛咳的效果。方法选择急诊全麻下开颅血肿清除术患者60例为研究对象,按照组间匹配的原则分为观察组和对照组,每组30例。观察组麻醉开始时微量泵持续泵注右美托咪定,直至缝皮结束,对照组泵... 详细信息

目的探讨脑出血开颅手术泵注右美托咪定预防术后呛咳的效果。方法选择急诊全麻下开颅血肿清除术患者60例为研究对象,按照组间匹配的原则分为观察组和对照组,每组30例。观察组麻醉开始时微量泵持续泵注右美托咪定,直至缝皮结束,对照组泵注等容量生理盐水。观察缝皮结束后自主呼吸恢复时间、出室时间,术后呛咳的发生率、丙泊酚追加次数和停药前及出室时平均动脉压(MAP)升高幅度。结果观察组呛咳发生率为16.67%,对照组为46.67%,组间比较差异有统计学意义(P0.05)。结论脑出血手术中泵注右美托咪定可以使术后呛咳发生率降低,稳定血流动力学,不增加恢复时间。

关键词：右美托咪定脑出血术后呛咳

右美托咪定与舒芬太尼镇痛的联合应用在妇科手术中效果及对患者情绪的影响

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国际精神病学杂志 2023年第6期50卷 1461-1464页

作者：吴梦淏管朝勇魏玲李佩河北省邢台市第三医院邢台054000

目的观察右美托咪定在妇科手术麻醉诱导期中与舒芬太尼镇痛的联合应用效果并评估其对焦虑抑郁情绪的影响。方法回顾性分析于我院(2021年01月-2023年01月)收治妇科手术患者500例,根据麻醉、镇痛药物选择方式不同进行分组,其中以右美托咪... 详细信息

目的观察右美托咪定在妇科手术麻醉诱导期中与舒芬太尼镇痛的联合应用效果并评估其对焦虑抑郁情绪的影响。方法回顾性分析于我院(2021年01月-2023年01月)收治妇科手术患者500例,根据麻醉、镇痛药物选择方式不同进行分组,其中以右美托咪定在麻醉诱导期中与舒芬太尼镇痛250例患者为研究组,另生理盐水+舒芬太尼镇痛另250例作为对照组。结果在术后6h、12h、24h研究组疼痛评分及焦虑抑郁情绪评分较术后1h升高,而研究组低于对照组(P<0.05)。研究组并发症总发生率低于对照组,但术中心率降低率高于对照组(P<0.05)。结论在妇科手术中,以右美托咪定与舒芬太尼镇痛的联合应用,可显著平稳患者生命体征,提高麻醉效果,降低术后患者疼痛感与焦虑、抑郁的不良情绪。

关键词：右美托咪定妇科手术舒芬太尼镇痛焦虑抑郁

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基于层次化Conformer的语音合成

计算机科学 2024年第2期51卷 161-171页

作者：吴克伟韩超孙永宣彭梦昊谢昭大数据知识工程教育部重点实验室(合肥工业大学) 合肥230601 情感计算与先进智能机器安徽省重点实验室(合肥工业大学) 合肥230601 合肥工业大学计算机与信息学院合肥230601

语音合成需要将输入语句的文本转换为包含音素、单词和语句的语音信号。现有语音合成方法将语句看作一个整体,难以准确地合成出不同长度的语音信号。通过分析语音信号中蕴含的层次化关系,分别设计基于Conformer的层次化文本编码器和基于... 详细信息

语音合成需要将输入语句的文本转换为包含音素、单词和语句的语音信号。现有语音合成方法将语句看作一个整体,难以准确地合成出不同长度的语音信号。通过分析语音信号中蕴含的层次化关系,分别设计基于Conformer的层次化文本编码器和基于Conformer的层次化语音编码器,并提出了一种基于层次化文本-语音Conformer的语音合成模型。首先,该模型根据输入文本信号的长度,构建层次化文本编码器,包括音素级、单词级、语句级文本编码器3个层次,不同层次的文本编码器描述不同长度的文本信息;并使用Conformer的注意力机制来学习该长度信号中不同时间特征之间的关系。利用层次化的文本编码器,能够找出语句中不同长度需要强调的信息,有效实现不同长度的文本特征提取,缓解合成的语音信号持续时间长度不确定的问题。其次,层次化语音编码器包括音素级、单词级、语句级语音编码器3个层次。每个层次的语音编码器将文本特征作为Conformer的查询向量,将语音特征作为Conformer的关键字向量和值向量,来提取文本特征和语音特征的匹配关系。利用层次化的语音编码器和文本语音匹配关系,可以缓解不同长度语音信号合成不准确的问题。所提模型的层次化文本-语音编码器可以灵活地嵌入现有的多种解码器中,通过文本和语音之间的互补,提供更为可靠的语音合成结果。在LJSpeech和LibriTTS两个数据集上进行实验验证,实验结果表明,所提方法的梅尔倒谱失真小于现有语音合成方法。

关键词：语音合成文本编码器语音编码器层次化模型 Conformer

Aerosol exposure assessment during reclaimed water utilization in China and risk evaluation in case of Legionella

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Frontiers of Environmental Science & Engineering 2022年第7期16卷 173-183页

作者： menghao Chen Liangliang Shi Gang Liu Xiaojin wu Yun Lu State Key Joint Laboratory of Environmental Simulation and Pollution Control State Environment Protection Key Laboratory of Microorganism Application and Risk ControlSchool of EnvironmentTsinghua UniversityBeijing100084China

Reclaimed water utilization provides an effective way to alleviate water ***,the residual pathogens in the recycled water like Legionella,could be spread into the air as aerosols through water-to-air transmission *** the aerosols by the people nearby increases their susceptibility to *** estimating the health risks associated with the potential exposure of airborne Legionella emitted from the urban use of reclaimed water in China,nationwide questionnaire was designed to investigate the exposure habits of Chinese population in different *** microbial risk assessment(QMRA)served as the suitable explanatory tool to estimate the *** results indicated that annual infection probability of populations exposed to Legionella for three scenarios,0.0764(95%CI:0.0032−0.6880)for road cleaning,1.0000(95%CI:0.1883−1.0000)for greenfield irrigation,0.9981(95%CI:0.0784−1.0000)for landscape fountain,were markedly higher than the threshold recommended by WHO(10^(−4) per person per year(pppy))according to the concentration distribution of Legionella in the reclaimed *** age-,educational background-,region-and gender-specific data in annual infection probability also showed different tendencies for some *** study provides some detailed information on the health risks from the water reuse in China and will be useful to promote the safe application of reclaimed water in water-deficient areas.

关键词： Legionella QMRA Reclaimed water Aerosol Water reuse

The variations of the Martian exobase altitude

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Earth and Planetary Physics 2020年第1期4卷 4-10页

作者： menghao Fu Jun Cui XiaoShu wu ZhaoPeng wu Jing Li Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai Guangdong 519082China Center for Excellence in Comparative Planetology Chinese Academy of SciencesHefei 230026China

The exobase is defined as the interface between the strongly collisional and the collisionless parts of an atmosphere. Although in reality the exobase is a transition region of finite depth, it is conventionally defined as the boundary above which an upwardly ejected neutral particle makes one collision at higher altitudes. Such an idealized definition is of practical use and serves as a good tracer of the overall size of an atmosphere as it expands and contracts under the influences of both external and internal sources. Knowledge of the atmospheric properties near the exobase is crucial to first-order estimates of atmospheric escape rates on terrestrial planets. Since its arrival at Mars on 21 September 2014, the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft has provided comprehensive maps of the Martian upper atmosphere under a variety of conditions. This allows, for the first time, a thorough investigation of the variations of the exobase altitude on this red planet. In this study, we use the N2 density measurements accumulated by MAVEN’s Neutral Gas and Ion Mass Spectrometer from October 2014 to November 2018 to determine the exobase altitudes for a large number of MAVEN orbits. Our analysis reveals clearly the variations of exobase altitude with local time and solar extreme ultraviolet (EUV) flux, as well as tentative evidence for the impact of global dust storms. These observations are indicative of thermal expansion of the Martian upper atmosphere, driven either externally by solar EUV energy deposition or internally by global dust storms.

关键词： Mars Exobase MAVEN

基于TOD的城市综合体与地铁站点连接模式研究

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建筑实践 2019年第9期 150-157页

作者：王桢栋陈有菲邬梦昊扈龑喆同济大学建筑与城市规划学院华东建筑设计研究院事业三部

当前,我国城市发展面临的挑战主要来自于机动车主导下的出行环境恶化,因而迫切需要调整市民出行结构并缩短出行距离。城市综合体与地铁站点的高效连接,能有助于促进公交出行。本文介绍了紧凑城市和公交导向开发的关联,分析了TOD背景下... 详细信息

当前,我国城市发展面临的挑战主要来自于机动车主导下的出行环境恶化,因而迫切需要调整市民出行结构并缩短出行距离。城市综合体与地铁站点的高效连接,能有助于促进公交出行。本文介绍了紧凑城市和公交导向开发的关联,分析了TOD背景下城市综合体发展的机遇,揭示了我国城市综合体与地铁连接不够紧密的问题,并讨论了三类连接模式的特点及其在城市开发更新中需注重的要点。

关键词：公交导向开发紧凑城市城市综合体地铁站点步行城市

缺血性脑血管病中血小板聚集率与CYP2C19基因多态性的相关性及不良预后因素分析

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现代实用医学 2024年第1期36卷 24-27页

作者：金孟浩吴丽君孙孟坊温州市中西医结合医院浙江省温州325000

目的探讨缺血性脑血管病中血小板聚集率与CYP2C19基因多态性的相关性及患者发生不良预后的影响因素。方法选取2020年10月至2021年12月于温州市中西医结合医院就诊的80例缺血性脑血管病患者作为研究对象,根据患者基因型分为快代谢组(n=... 详细信息

目的探讨缺血性脑血管病中血小板聚集率与CYP2C19基因多态性的相关性及患者发生不良预后的影响因素。方法选取2020年10月至2021年12月于温州市中西医结合医院就诊的80例缺血性脑血管病患者作为研究对象,根据患者基因型分为快代谢组(n=29)、中代谢组(n=37)及慢代谢组(n=14),各组患者均采用氯吡格雷进行治疗。比较各组患者血小板聚集率及治疗12个月后不良事件发生情况,采用Spearman法对血小板聚集率与CYP2C19基因多态性进行相关性分析,采用Logistics回归分析影响患者发生不良事件的相关因素。结果治疗后12个月后,3组血小板聚集率、血小板抑制率差异均有统计学意义(均P<0.05);CYP2C19基因多态性与血小板聚集率呈正相关(r=0.716,P <0.05),与血小板抑制率呈负相关(r=-0.531,P <0.05);快代谢组不良事件发生率低于慢代谢组(P <0.05)。根据是否发生不良预后分为两组,单因素分析显示两组年龄、体质量指数、是否患有高血压、是否患有糖尿病、血脂是否异常、基因型及血脂聚集率差异均有统计学意义(均P<0.05);Logistics分析结果显示,血小板聚集率过高、血脂异常、年龄较大、体质量指数较高是影响患者发生不良事件的相关因素(均P<0.05)。结论缺血性脑血管病患者血小板聚集率及预后与CYP2C19基因多态性密切相关,并且血小板聚集率过高、血脂异常、年龄较大及体质量指数较高将提高患者发生不良预后风险。

关键词：缺血性脑血管病血小板聚集率基因多态性预后影响因素

Pneumatic and tendon actuation coupled muti-mode actuators for soft robots with broad force and speed range

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Science China(Technological Sciences) 2022年第9期65卷 2156-2169页

作者： ZHU JiaQi PU menghao CHEN Han XU Yi DING Han wu ZhiGang State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Broad output force and speed ranges are highly desired for actuators to endow soft robots with high performance,thereby increasing the range of tasks they can ***,limited by their low structural stiffness and single actuation method,most of the existed soft actuators are still difficult to achieve a broad force and speed range with a relatively compact body ***,we propose a pneumatic and tendon actuation coupled soft actuator(PTCSA)with multiple actuation modes,mainly composing of a multi-joint thermoplastic polyurethanes(TPU)-made skeleton sealed in a film *** TPU skeleton with certain structural stiffness combined with soft joints allows PTCSA to output small force and respond rapidly under pneumatic actuation,as well as output high force and flexibly regulate response speed under tendon actuation,therefore achieving a broad force and speed range with a compact *** multiple modes constructed from the two actuation methods with different force and speed properties can cover diverse application *** demonstrate its performance,PTCSA is further used to construct a soft robotic arm(with a maximum lifting speed of 198°/s and can easily lift a load of 200 g),an inchworm-inspired wheel-footed soft robot(moves at a high speed of 2.13 cm/s when unload or pulls a load of 300 g forward),and a soft gripper(can grasp diverse objects,from 0.1 g potato chips to an 850 g roll of Sn-0.7 Cu wire,from a high-speed moving tennis ball to an upright pen).This work indicates the potential of combining multiple complementary actuation methods to improve the force and speed range of soft actuators,and may provide inspiration for related research.

关键词： soft actuator tendon actuation pneumatic actuation broad force and speed range multiple modes

基于可见-近红外光谱技术的广东典型地区耕地土壤养分含量预测模型评估

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华南农业大学学报 2024年第2期45卷 218-226页

作者：钟鹤森李玮张泽宇吴玲鄂东梅张孟豪许腾伟戴军张池华南农业大学资源环境学院广东广州510642 中国农业大学土地科学与技术学院北京100193 福斯华(北京)科贸有限公司北京100081

【目的】可见-近红外光谱(Visible-near infrared spectroscopy,VNIRS)可以利用少量土壤样品建立预测模型,从而无损快速地预测土壤养分含量。然而,至今鲜见广东省土壤养分的VNIRS预测模型的报道。本研究旨在通过传统化学分析方法和VNIR... 详细信息

【目的】可见-近红外光谱(Visible-near infrared spectroscopy,VNIRS)可以利用少量土壤样品建立预测模型,从而无损快速地预测土壤养分含量。然而,至今鲜见广东省土壤养分的VNIRS预测模型的报道。本研究旨在通过传统化学分析方法和VNIRS技术对广东典型地区的耕地土壤进行分析,构建土壤全量及速效养分含量的VNIRS预测模型,并评估利用光谱分析土壤全量和速效养分含量的可行性,为广东省土壤养分的快速检测及质量评估提供科学参考。【方法】本研究采集了粤东(梅州)、粤西(湛江)、粤北(韶关)、粤西北(肇庆)和珠三角(惠州和珠海) 5个地区共514份耕地土壤样品,测量样品有机质、全氮、可溶性有机碳、碱解氮和速效磷含量,同时利用VNIRS在400~2 490 nm波长范围内探明其全光谱特征,筛选定标样品,结合偏最小二乘法和主成分分析,建立预测模型,并在此基础上进行反向验证,评估模型的可行性。【结果】各地区土壤有机质、全氮、可溶性有机碳、碱解氮和速效磷含量及光谱特征均存在显著差异。有机质和全氮的定标预测模型效果较好,其中,粤西北地区的有机质定标相关系数达到0.831 1,珠三角地区的全氮定标相关系数达到0.789 8;可溶性有机碳、碱解氮和速效磷的预测模型效果在地区间差异较大,粤西北和珠三角地区碱解氮和速效磷的定标效果远优于其他地区。反向验证结果表明,有机质和全氮的预测值与实测值具有较好的相关性,决定系数(R2)最高分别达到0.69和0.65;粤西北和珠三角地区碱解氮的反向验证结果也较好,R2达到0.63和0.62;而可溶性有机碳和速效磷的反向验证结果总体较差。【结论】VNIRS技术能够区分省域内不同地区的土壤来源,可以作为未来土壤分类和土壤质量调查的重要评价指标。VNIRS技术能够较好地直接预测耕地土壤有机质和全氮含量,对可溶性有机碳、碱解氮、速效磷含量的预测存在明显元素差别和地区差异,今后需进一步筛选光谱范围或采用更优方式构建模型。

关键词：可见-近红外光谱广东耕地土壤土壤养分偏最小二乘法

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