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Bio-inspired vibrational wireless underground communication system

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第4期14卷 1042-1051页

作者： Yi Zhong Junliang(julian)Tao Center for Bio-mediated and Bio-inspired Geotechnics School of Sustainable Engineering and the Built EnvironmentArizona State UniversityTempeAZ85287USA

The internet of the underground things(IoUT)is an emerging field that concerns connected underground sensing nodes and can find applications in various fields such as geotechnical engineering,precision agriculture,and search and rescue *** complex underground environment and multiphase nature of the soil pose challenges to wireless underground *** existing studies on wireless underground communication focus on the use of electromagnetic ***,as a highly lossy material for electromagnetic waves,soil can limit the range and reliability of data *** by subterranean animals that rely on vibrations or seismic waves for underground communication,the prototype system developed in this study is based on *** system includes a bioinspired vibrating source,a micro-electromechanical system(MEMS)accelerometer,a microcontroller,and a set of algorithms for encoding and decoding ***,the mole ratsinspired source is small in size,low in cost,and *** on-off-keying decoding algorithm enhanced with an error-correction algorithm is found to be robust in transmitting textual and imaginary *** the current design,a maximum transmission bit rate of 16e17 bits per second and a transmission distance of 80 cm can be *** bit error ratio is as low as 0.1%,demonstrating the robustness of the *** performance of the developed system shows that seismic waves produced by vibration can be used as an information carrier and can potentially be implemented in the IoUT.

关键词： Bio-inspired vibration Underground communication Seismic wave Wireless communication Internet of underground things(IoUT)

重复荷载作用后海工高性能混凝土梁刚度退化试验研究

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土木与环境工程学报（中英文） 2024年第3期46卷 171-179页

作者：陆春华吴小龙蔡启明张菊连江苏大学土木工程与力学学院江苏镇江212013 上海宏信建筑科技有限公司上海201800

在荷载长期作用下,钢筋混凝土受弯构件的变形是一个重要的评价指标,也是构件正常使用极限状态的验算内容之一。为了研究经历重复荷载后海工高性能混凝土梁的变形发展规律,设计制作了10根试验梁,分别进行了重复荷载试验、氯盐干湿试验以... 详细信息

在荷载长期作用下,钢筋混凝土受弯构件的变形是一个重要的评价指标,也是构件正常使用极限状态的验算内容之一。为了研究经历重复荷载后海工高性能混凝土梁的变形发展规律,设计制作了10根试验梁,分别进行了重复荷载试验、氯盐干湿试验以及两者的共同作用试验;通过四点受弯试验对梁的跨中挠度及刚度退化进行评价,提出了梁短期刚度规范计算公式的修正方法。研究结果表明:荷载水平按梁纯弯段弯矩等于0.4M_(u)确定时,施加30次重复荷载后混凝土的损伤度接近15%;对于仅进行氯盐干湿循环的试验梁,其跨中挠度发展要慢于参照梁;施加重复荷载后,试验梁的跨中挠度发展要快于参照梁;对施加重复荷载后的试验梁再进行氯盐干湿循环,梁的刚度退化更为显著。结合试验结果,采用损伤效应折减系数对梁短期刚度计算公式进行修正,并验证了修正公式的合理性和有效性。

关键词：重复荷载海工混凝土梁损伤度氯盐环境弯曲刚度

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Advantages of a Biomimetic Stiffness Profile in Pitching Flexible Fin Propulsion

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Journal of Bionic Engineering 2010年第2期7卷 113-119页

作者： Paul Riggs Adrian Bowyer julian Vincent Biomimetics Group Mechanical Engineering DepartmentUniversity of Bath

The use of oscillating flexible fins in propulsion has been the subject of several studies in recent years, but attention israrely paid to the specific role of stiffness profile in thrust *** profile is defined as the variation in localchordwise bending stiffness (EI) of a fin, from leading to trailing *** this study, flexible fins with a standard NACA0012shape were tested alongside fins with a stiffness profile mimicking that of a Pumpkinseed Sunfish (Lepomis gibbosus).The finswere oscillated with a pitching sinusoidal motion over a range of frequencies and amplitudes, while torque, lateral force andstatic thrust were *** the range of oscillation parameters tested, it was shown that the fin with a biomimetic stiffness profile offered a significantimprovement in static thrust, compared to a fin of similar dimensions with a standard NACA0012 aerofoil *** fin also produced thrust more consistently over each oscillation cycle.A comparison of fin materials of different stiffness showed that the improvement was due to the stiffness profile itself, andwas not simply an effect of altering the overall stiffness of the *** of the same stiffness profile were observed to follow thesame thrust-power curve, independent of the stiffness of the moulding *** fins were shown to produce up to26% greater thrust per watt of input power, within the experimental range.

关键词： biomimetic propulsion stiffness pitching flexible fin

Design and optimization of thermally responsive autonomous dynamic glazed attachment systems for building solar heat gain control

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Building Simulation 2023年第10期16卷 1971-1986页

作者： Neda Ghaeili Ardabili Yanxiao Feng julian Wang Department of Architectural Engineering Pennsylvania State UniversityUniversity ParkPA16802USA

Windows,as transparent intermediaries between the indoors and outdoors,have a significant impact on building energy consumption and indoor visual and thermal *** the recent development of dynamic window structures,especially various attachment technologies,the thermal,visual,and energy performances of windows have been significantly *** this research,a new dynamic transparent louver structure sandwiched within conventional double-pane windows is proposed,designed,optimized,and examined in terms of energy savings in different *** uniqueness of the proposed design is that it autonomously responds to the seasonal needs prompted by solar heat gain through the use of thermally deflected bimetallic ***,by integrating spectral selective louvers into the system design,the dynamic structure enables strong solar infrared modulation with a little visible *** optical and thermal properties of the dynamic glazing structure support about 30%and 16%seasonal variations in solar heat gains and visible transmittance,***,the potential energy savings were explored via parametric energy simulations,which showed significant potential for heating and cooling energy *** proposed design demonstrates a simple smart dynamic glazing structure driven by seasonal temperature differences,with significant solar heat control capabilities and minor effects on the visible or visual quality of the glazing system.

关键词： smart window window attachment spectrally selective louver solar heat gain visible transmittance bimetal structure

A new guideline for diagnosis and treatment of syncope in children and adolescents that stimulates further thought and discussion

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Science Bulletin 2018年第23期63卷 1527-1528页

作者： julian M.Stewart Physiology and Medicine Center for HypotensionThe New York Medical CollegeValhallaNY 10595USA

A new guideline for diagnosis and treatment of syncope in children and adolescents was published by Chinese Pediatric Cardiology Society (CPCS)[1].This guideline admirably outlines a differential diagnosis of syncope in the Chinese population,placing appropriate emphasis on vasovagal syncope (VVS,simple faint), the most common *** authors appropriately discuss other more ominous causes of syncope such as cardiogenic syncope and neurogenic orthostatic *** particular,cardiogemc syncope can have lethal consequences if not promptly treated.

关键词： Children Adolescent syncope CPCS

Asian Urban Environment and Climate Change: Preface

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Journal of Environmental Sciences 2017年第9期29卷 1-5页

作者： julian Hunt Jianping Wu University College London and Trinity College University of Cambridge School of Civil Engineering Tsinghua University

The Asian Network on Climate Science and Technology （***）, in collaboration with Tsinghua University, held a conference on environmental and climate science, air pollution, urban planning and transportation in July 2015, with over 40 Asian experts participating and presentation. This was followed by a meeting with local government and community experts on the practical conclusions of the conference. Of the papers presented at the conference a selection are included in this special issue of ]ournal of Environmental Science, which also reflects the conclusions of the Paris Climate meeting in Dec 2015, when the major nations of the world agreed about the compelling need to reduce the upward trend of adverse impacts associated with global climate change. Now is the time for urban areas to work out the serious consequences for their populations, but also how they should work together to take action to reduce global wanning to benefit their own communities and also the whole planet!

关键词： Urban transportation

Monitoring spatiotemporal soil moisture changes in the subsurface of forest sites using electrical resistivity tomography (ERT)

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Journal of Forestry Research 2022年第5期33卷 1649-1662页

作者： julian Fäth Julius Kunz Christof Kneisel Institute of Geography and Geology University of WürzburgAm Hubland97074 WürzburgGermany

The effects of drought on tree mortality at forest stands are not completely understood. For assessing their water supply, knowledge of the small-scale distribution of soil moisture as well as its temporal changes is a key issue in an era of climate change. However, traditional methods like taking soil samples or installing data loggers solely collect parameters of a single point or of a small soil volume. Electrical resistivity tomography (ERT) is a suitable method for monitoring soil moisture changes and has rarely been used in forests. This method was applied at two forest sites in Bavaria, Germany to obtain high-resolution data of temporal soil moisture variations. Geoelectrical measurements (2D and 3D) were conducted at both sites over several years (2015-2018/2020) and compared with soil moisture data (matric potential or volumetric water content) for the monitoring plots. The greatest variations in resistivity values that highly correlate with soil moisture data were found in the main rooting zone. Using the ERT data, temporal trends could be tracked in several dimensions, such as the interannual increase in the depth of influence from drought events and their duration, as well as rising resistivity values going along with decreasing soil moisture. The results reveal that resistivity changes are a good proxy for seasonal and interannual soil moisture variations. Therefore, 2D- and 3D-ERT are recommended as comparatively non-laborious methods for small-spatial scale monitoring of soil moisture changes in the main rooting zone and the underlying subsurface of forested sites. Higher spatial and temporal resolution allows a better understanding of the water supply for trees, especially in times of drought.

关键词： Geoelectrical monitoring Forest ecology Hydrology Soil water content

The Materials Revolution

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Journal of Bionic Engineering 2006年第4期3卷 217-234页

作者： julian F.V.Vincent Department of Mechanical Engineering The University of Bath Bath BA2 7AY UK

In the final essay of this series the gaps between biology and engineering are examined, and methods are suggested for crossing them. Creativity is seen as the essential, and TRIZ （the Russian Theory of Inventive Problem Solving） is recommended as the best set of methods both for stimulating creativity and for solving technical problems. When the catalogue of Inventive Principles of TRIZ is used to bring biology and technology to the same level of detail, the comparison shows that the similarity is only about 12%. The differences largely reside in the reliance of energy as a controlling parameter in conventional technology and the replacement of energy by information in biological systems. Although we might be moving slowly in this direction, a numerically based comparison such as this should provide more impetus.

关键词： The Materials Revolution

麦二叉蚜唾液蛋白基因Sg1655时空表达谱及其抑制小麦防御反应的功能

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植物保护学报 2024年第1期51卷 20-27页

作者：孙钰张雨濛刘晓蓓陈巨莲张勇解海翠河北科技师范学院河北省作物逆境生物学重点实验室秦皇岛066600 中国农业科学院植物保护研究所植物病虫害综合治理全国重点实验室北京100193

为进一步明确麦二叉蚜Schizaphis graminum唾液蛋白Sg1655在调控小麦防御反应中的作用,基于麦二叉蚜唾液腺转录组数据,利用PCR技术克隆获取Sg1655开放阅读框,利用生物信息学软件对其序列进行分析;通过实时荧光定量PCR(real-time quantit... 详细信息

为进一步明确麦二叉蚜Schizaphis graminum唾液蛋白Sg1655在调控小麦防御反应中的作用,基于麦二叉蚜唾液腺转录组数据,利用PCR技术克隆获取Sg1655开放阅读框,利用生物信息学软件对其序列进行分析;通过实时荧光定量PCR(real-time quantitative PCR,RT-qPCR)技术检测Sg1655在麦二叉蚜不同组织及不同龄期中的表达;利用细菌III型分泌系统将Sg1655导入到小麦叶片内,检测其瞬时表达对小麦胼胝质积累的影响。结果表明,Sg1655开放阅读框全长375 bp,编码125个氨基酸残基,N端1~21位为信号肽序列,预测蛋白分子量为14.90 kD。麦二叉蚜Sg1655氨基酸序列与玉米蚜Rhopalosiphum maidis同源序列相致性最高,为89.52%;麦二叉蚜Sg1655与玉米蚜同源序列聚为一个分支,亲缘关系最近。Sg1655在麦二叉蚜各组织中均有表达,其中在唾液腺中表达量最高,Sg1655在麦二叉蚜各个龄期均有表达,且在不同龄期之间无显著差异。小麦叶片内Sg1655瞬时表达可显著抑制小麦胼胝质积累,表明该蛋白可作为潜在效应子参与抑制小麦防御反应。

关键词：麦二叉蚜唾液蛋白 Sg1655 基因克隆序列比对时空表达谱功能分析