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Journal of Bionic Engineering 2020年第1期17卷 45-54页

作者： Qingsong He Xianrui Xu Zhiwei Yu Kai Huo Zhaoyang Wang Nuo Chen Xuean Sun Gui Yin Peile Du Yang Li Zhendong Dai Institute of Bio-inspired Structure and Surface Engineering Jiangsu Provincial Key Laboratory of Bionic Functional MaterialsCollege of Mechanical and Electrical EngineeringNanjing University of Aeronautics&AstronauticsNanjing 210016China College of Astronautics Nanjing University of Aeronautics&AstronauticsNanjing 210016China China Ship Development and Design Center Shanghai Branch Shanghai 201108China

Various bio-inspired dry adhesive materials have been investigated.In this work,lithography and silicon deep etching method were used to fabricate bio-inspired micro-pillar dry adhesive materials of which the parameters,such as side length,Height to Side length Aspect Ratio(HSAR),and inter-pillar Distance to Side length Aspect Ratio(DSAR)were comprehensively studied to obtain a dry adhesive with high adhesion.An orthogonal array method was designed and a series of fabrication experiments were conducted to identify optimum parameters,which resulted in a high normal adhesion of 2.98 N·cm^-2 and a shear adhesion of 9.59 N·cm^-2.An adhesion and desorption device was further designed on basis of the optimum dry adhesive,which enables an Unmanned Aerial Vehicle(UAV)to successfully adhere on and detach from a ceiling.This would allow an UAV to stay aloft for prolonged time,which could be invaluable to many applications,such as energy conservation and aerial detection.

关键词： bio-inspired dry adhesive orthogonal array method UAV adhere ceiling

Duty Cycle of a Radiant ceiling Heating System under Extremely Cold-Temperature Conditions:A Theoretical Assessment

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Journal of Energy and Power Engineering 2019年第10期13卷 359-368页

作者： Mohamed Lateb Hachimi Fellouah Department of Mechanical Engineering Universitéde Sherbrooke2500 Blvd.de l’UniversitéSherbrookeQC J1K 2R1Canada

This work focuses on the estimation of a duty cycle of a radiant ceiling heating system with a panel surface temperature of 35℃and a heat flux of 65 W/m2 that corresponds to a thermal comfort for sedentary occupants.The results obtained are based on the theoretical heat transfer equations that govern the radiant and natural convection heat exchange mechanisms,and experimental heat transfer coefficients available in the literature.The results of the examined radiant heating system with specific conditions showed that a duty cycle of 6.46 min alternated by 13.36 min in shutting-down position is required to assure an acceptable thermal comfort for the enclosure space occupants.In addition,the study showed that for extremely cold-temperature conditions the heating system requires a daily operating load of about 61.2%which clearly proves the efficiency of these radiant heating systems in terms of energy consumption.

关键词： Radiant ceiling panels natural convection transfer thermal comfort radiant heating systems duty cycle energy consumption.

Modified ceiling Bounce Model for Computing Path Loss and Delay Spread in Indoor Optical Wireless Systems

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International Journal of Communications, Network and System Sciences 2009年第8期2卷 754-758页

作者： K. SMITHA A. SIVABALAN J. JOHN 不详

This paper proposes modifications to the tradional ceiling Bounce Model and uses it to characterize diffuse indoor optical wireless channel by analyzing the effect of transceiver position on signal propagation properties. The modified approach uses a combination of the tradional ceiling bounce method and a statistical approach. The effects of different transmitter-receiver separations and height of the ceiling on path loss and delay spread are studied in detail.

关键词： Indoor Optical Channel Modified ceiling Bounce Model Path Loss Delay Spread

Effect of Slope Degree on the Lateral Bending in Gekko geckos

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Journal of Bionic Engineering 2015年第2期12卷 238-249页

作者： Zhouyi Wang Lei Cai Wei Li Aihong Ji Wenbo Wang Zhendong Dai Institute of Bio-Inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A gecko＇s habitat possesses a wide range of climbing slopes that pose a number of postural challenges for climbing lo- comotion. Few studies have examined the relationship between the lateral bending of the trunk of a gecko and other aspects of locomotion when climbing. In this paper, three-dimensional reaction forces and high-speed videos of Gekko geckos moving on different slopes are used to reveal how the lateral bending of the animal＇s trunk responds to changing slopes. The results of such observations indicate that the minimum bending radius continually decreases with an increase in the slope, illustrating that the degree of bending of the trunk becomes significantly greater. Moreover, a lateral bending mechanical model is used to show the interrelation between the lateral bending in the frontal plane and the sagittal deformation of the trunk caused by gravity. Taken together, these results have advanced our understanding of the role of lateral bending of vertebrates when climbing on a slope.

关键词： slope lateral bending reaction force gecko ceiling

Morphology and reaction force of toes of geckos freely moving on ceilings and walls

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Science China(Technological Sciences) 2010年第6期53卷 1688-1693页

作者： WANG ZhouYi1,2,GU WenHua1,2,WU Qiang1,2,JI AiHong1 & DAI ZhenDong1 1 Institute of Bio-inspired Structure and Surface Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China 2 College of Mechanical and Electrical Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing China

The 3-dimensional interactions between toes of a gecko and substrates (ceilings or walls) were measured when it moves on ceilings or walls by using a 3-dimensional force measuring array,and the correspondent morphology of the gecko toes was recorded by a high speed camera.The study aims to understand the relationship between adhesive and shear forces generated by the toes of the gecko and the locomotion behavior when it walks on walls and ceilings.Results showed that shear force is along the toe-only 12.6° and 3.1° away from the toe for wall-climbing and ceiling-crawling,respectively while the adhesion is big enough to balance the body weight and moment.The shear forces generated by the first and the fifth toes are in opposite directions;this redundant force increases the reliability of adhesion and stability of locomotion.The support angles of toes are equal approximately for ceiling-crawling and wall-climbing.The study greatly inspires the design of a gecko-like robot.

关键词： reaction force of toe morphometrics ceiling redundant force gecko-like robot

建筑设计生成方法教学研究——“ceiling Margin”生成工具工程实践

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新建筑 2008年第3期 17-23页

作者：李飚钱敬平东南大学建筑学院南京210096

计算机生成方法通过相关算法对建筑元素自组织优化组合,借助传统设计方法不易获得的艺术灵感,它将生成系统作为全新建筑设计方法并趋向艺术实践的程序创作系统。介绍了东南大学2007毕业班建筑生成设计研究组的教学探索及工程实践,通过"c... 详细信息

计算机生成方法通过相关算法对建筑元素自组织优化组合,借助传统设计方法不易获得的艺术灵感,它将生成系统作为全新建筑设计方法并趋向艺术实践的程序创作系统。介绍了东南大学2007毕业班建筑生成设计研究组的教学探索及工程实践,通过"ceiling Margin"吊顶生成工具的程序开发、加工及安装,阐述全新建筑设计生成方法。

关键词： ceiling Margin 生成方法吊顶

Green Light for PPP on German Motorways?

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Frontiers of Law in China-Selected Publications from Chinese Universities 2019年第3期14卷 311-334页

作者： Hartmut Bauer Michael Meier Augsburg University AugsburgGermany Faculty of Law Potsdam UniversityPotsdam 14482Germany LL.B. Bucerius Law SchoolHamburgGermany

While public-private partnerships(PPPs)have surged worldwide since the 1990s,they have been met with growing skepticism during the last years.A recent revision of Germany's constitutional rules on motorway construction and observations on the use of PPPs published by both the German and the European Courts of Auditors illustrate this new caution.These two examples fit into a general trend towards a revival of the public sector,which can be summarized under the cross-level umbrella term"publicization."It would,however,be remiss to replace the uncritical euphoria that once surrounded privatization with a similarly undifferentiated euphoria regarding publicization.Rather,it is crucial to identify the most appropriate solution for the fulfilment of each public task from the"toolbox"of publicization on the one hand and privatization on the other hand in order to ensure the most effective completion of public functions.

关键词： publicization remunicipalization recommunalization nationalization renationalization public-private partnerships PPPs privatization motorways infrastructure construction toll economic efficiency court of auditors debt ceiling economic impact analysis

西门子Artis zee ceiling血管造影系统故障维修分析

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中国医疗器械信息 2018年第16期24卷 149-150页

作者：陈洋兴梧州市工人医院广西梧州543001

西门子Artis zee ceiling血管造影系统为德国制造,设备具有先进性能且应用灵活,所获取的图像清晰,是临床中对心脑血管疾病诊治的有效辅助工具。这一仪器不仅能提供二维造影,还可实现三维数字减影成像,也即3D成像。在具体应用中,西门子Ar... 详细信息

西门子Artis zee ceiling血管造影系统为德国制造,设备具有先进性能且应用灵活,所获取的图像清晰,是临床中对心脑血管疾病诊治的有效辅助工具。这一仪器不仅能提供二维造影,还可实现三维数字减影成像,也即3D成像。在具体应用中,西门子Artis zee ceiling血管造影系统有时会出现一些故障,需手动排除。本研究结合笔者临床实践中的一些经验,对西门子Artis zee ceiling血管造影系统常见故障及其维修方法加以总结,以期为广大同仁提供一些参考。

关键词：西门子 Artis zee ceiling 管造影系统常见故障维修方法

中国GBZ2Q1与美国ACGIH工作场所化学有害因素职业接触限值比较研究

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中华劳动卫生职业病杂志 2014年第1期32卷 1-26页

作者：李文捷张敏王丹中国疾病预防控制中心职业卫生与中毒控制所北京100050

目的将我国职业卫生标准GBZ2．1中规定的与ACGIH于2013年发布的化学有害因素职业接触限值（OELs）数量、水平、制定和管理过程等方面进行系统比较，并提出我国职业卫生标准制修订过程中优先考虑的化学物质OELs及有关建议，为制定职业卫... 详细信息

目的将我国职业卫生标准GBZ2．1中规定的与ACGIH于2013年发布的化学有害因素职业接触限值（OELs）数量、水平、制定和管理过程等方面进行系统比较，并提出我国职业卫生标准制修订过程中优先考虑的化学物质OELs及有关建议，为制定职业卫生标准规划计划提供基础数据和参考。方法将GBZ2．1中规定的OELs与美国ACGIH2013年采纳的化学有害因素OELs按照不同类型的限值建立比较分析数据库，并进行限值的数量、具体职业性有害因素的具体值及其关键效应、法律地位、制定原则、制定依据、制定条件、制定程序、关键效应、化学有害因素的致癌性标识的应用、化学有害因素的致敏性标识的应用、化学有害因素的经皮标识的应用、非常规工作制下对OELs的调整、联合作用的概念及其应用、超限倍数的概念和应用及对颗粒物的标识等方面的比较分析。结果（1）GBZ2．1中共规定了339种化学有害因素的OELs，美国ACGIH2013年已采纳TLVs的化学有害因素有656种。GBZ2．1有OELs而ACGIH未规定OELs的化学有害因素只有52个；ACGIH有OELs，GBZ2．1中无OELs的化学有害因素共有371个。在GBZ2．1和ACGIH中均规定了OELs的化学有害因素共260种，涉及302个OELs，其中GBZ2．1有47个比ACGIH宽，96个比ACGIH严，81个与ACGIH相近，77个与ACGIH相等。（2）化学有害因素的致癌性、致敏性和经皮标识的应用方面我国尚未制定评估的指南性文件；（3）在非常规工作制调整指南方面我国即将出台更详细的标准；（4）我国与ACGIH在限值制定和管理程序的多个方面仍存在较大差距。我国OELs制定的管理和审批程序较为繁琐，但与ACGIH相比，科学性和可行性不足。结论（1）我国应尽快制定化学有害因素的致癌性、致敏性和经皮标识评估的指南性文件。（2）应尽快确定我国OELs研究的工作重点，缩小我国OELs与发达国家的差距，满足社会经济发展的需求。优先调整过宽和过严的OELs；对ACGIH已有OELs但GBZ2．1中尚未制定OELs的371种化学有害因素，应根据我国职业卫生实践确定需要优先制定职业接触限值的重点有害因素。（3）应采用系统性综述的方法，为修订OELs提供最新的科学证据。（4）尽快解决我国对超限倍数的理解和应用问题，非常规工作制下调整OELs，阐述和应用联合作用，标识化学有害因素OELs所适用的化学有害因素的物理状态等几个重要的关键技术问题。

关键词： GBZ 2 1 ACGIH TWA STEL MAC ceiling 化学有害因素职业接触限值比较研究

Reconstruction and Restoration of Main Facade and Wooden ceilings of Hasan Basha Tahir Kuttab &Sabil, Cairo—Egypt

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World Journal of Engineering and Technology 2019年第1期7卷 175-192页

作者： Mahran F. Anwar Conservation Department Institute of Tourism Hotel Management and Restoration Alexandria

The architectural?complexes?of Hasan Basha Tahir?were suffering from many damages and deformation in different elements as load bearing walls, arches and wooden ceiling. Ground water, salt weathering, air pollution, biological colonization and environmental aspects were the main degradation factors which caused a lot of damage and deterioration phenomena in the complexes. Horizontal and vertical cracks, salts, loss of decorations, and featured dark of the stone surface were noticed at the complexes elements. In addition, the celling of the complex was in a very bad condition;?it had lost a lot of decoration elements, cracking, soot deposition, insects’ holes, and fungi growth. This research will discuss the various deterioration phenomena that?have?effect on the main building materials and cause the damages and discuss the general scientific methodology of the architectural and structural conservation project which was?carried out.

关键词： Architectural Complexes Ottoman Period Damages ceiling Construction Bearing Wall Conservation Re-Construction