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Micromorphological description of vernacular cob process and comparison with rammed earth

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Frontiers of Architectural Research 2020年第1期9卷 203-215页

作者： Erwan Hamard Cécilia Cammas Blandine Lemercier Bogdan Cazacliu Jean-Claude Morel IFSTTAR MASTGPEMF-44344BouguenaisFrance INRAP UMR 5140AgroParisTechF-78850Thiverval-GrignonFrance UMR SAS AGROCAMPUS OUESTINRAF-35042RennesFrance Faculty of Engineering Environment and ComputingCentre for the Built and Natural EnvironmentCoventry UniversityCoventryCV15FBUK

Past builders have developed very low-embodied energy construction techniques optimizing the use of local building *** techniques are a source of inspiration for modern sustainable ***,this know-how was orally transmitted and was lost as earth construction fell into disuse during the 20th century in European *** absence of written documents makes necessary to use an archaeological approach in order to rediscover these construction *** analysis of thin sections collacted in earth building walls was used for the first time to describe cob construction technique and highlighted several typical pedofeatures allowing to clearly identifying this ***,a first comparison of the cob and rammed earth micromorphological features permitted to identify two key factors to distinguish these two techniques,the manufacturing state(solid or plastic)and the organization of the material in the wall.

关键词： cob Rammed earth Micromorphology Architectural heritage Pedology

Research on cob De-embedding in Scattering Parameter Measurement

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Journal of Harbin Institute of Technology(New Series) 2017年第1期24卷 37-42页

作者： Lei Wang Jingyi Zhang Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai UniversityShanghai 200333China Shanghai Huahong Grace Semiconductor Manufacturing Corporation Shanghai 201203China

The popular radio frequency(RF) chip on board(cob) test has gradually taken the place of onwafer test due to the high efficiency and high power. This paper presents the extended Open-Short-Load(OSL) that is one-port calibration method to verify the error model de-embedding in S parameter measurement. Threelevel cascade structure on cob's system error model is proposed and analyzed. Four kinds of calibration plane solutions for de-embedding are verified. At last,on-board calibration(CAL) kits solution is established to decrease the system error to the least value. The maximum error shift can be controlled less than 0.1 dB comparing with the on-wafer test results. In general,the practical application results prove that this method is reasonable and effective and easy to be mastered.

关键词： S parameter cob de-embedding

INDEX AND ENGINEERING PROPERTIES OF OREGON cob

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Journal of Green Building 2011年第2期6卷 88-106页

作者： Quinn M.Pullen Todd V.Scholz Honors Baccalaureate School of Civil and Construction EngineeringOregon State UniversityCorvallisOregon 97331 School of Civil and Construction Engineering Oregon State UniversityCorvallisOregon 97331

cob is an earthen building material comprised of sand,clay,straw,and water used for millennia to construct *** cob construction largely died out during the nineteenth century,it is experiencing a revival in England and the Pacific Northwest of the United *** scientific research has investigated the engineering properties of cob,knowledge of which is important for modern-day design practices and code *** at Oregon State University investigated six different Oregon cob mixtures using a series of standard soils and concrete tests adapted for this *** objectives were to characterize the constituents,to establish estimates for the magnitude of,and degree of variability in,the mixture properties,and to develop correlations between the engineering properties and mixture *** indicated low to moderate variation in basic mixture properties(i.e.,unit weight,moisture content,and sand equivalent),moderate variation in strength properties,and high variation in the elastic *** reasonable correlations were found between shrinkage,compressive strength,elastic modulus,and sand equivalent and between flexural strength and fiber tensile strength.

关键词： cob Oregon cob earthen building material properties

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化学镀cob薄膜动力学参数的回归分析

华中科技大学学报（自然科学版） 2005年第7期33卷 54-57页

作者：刘昌辉何华辉李海华邱静华中科技大学电子科学与技术系湖北武汉430074 武汉市排水设施监督管理处湖北武汉430074

根据化学镀cob薄膜试验得到镀液中反应物浓度、pH值、温度以及对应沉积速率.利用回归分析法,建立一元线性回归处理的数学模型和多元线性回归处理的数学模型.实验数据的拟合程度用相关系数R与剩余方差S来表征,借助于计算机编程运算,求出... 详细信息

根据化学镀cob薄膜试验得到镀液中反应物浓度、pH值、温度以及对应沉积速率.利用回归分析法,建立一元线性回归处理的数学模型和多元线性回归处理的数学模型.实验数据的拟合程度用相关系数R与剩余方差S来表征,借助于计算机编程运算,求出回归系数的估计值b0-3、估计值的置信区间、残差r、残差的置信区间rint.分别确定上述诸因素所对应的反应动力学参数,并求出镀液中反应物浓度、pH值、温度与对应沉积速率的对数关系曲线表达式,导得了镀液沉积速率的方程式.优化了实验方案,确定了镀液的构成和工艺条件,成功制备了性能良好的合金镀层.

关键词： cob 回归分析法动力学计算机编程化学镀沉积速率

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SOI像素探测器的cob组装工艺初步研究

核电子学与探测技术 2015年第6期35卷 607-611页

作者：辛虹阳卢云鹏刘义董静康玺欧阳群南华大学核科学技术学院湖南衡阳421001 中国科学院高能物理研究所北京100049 核探测与核电子学国家重点实验室北京100049 中国科学院大学北京100049

从子板PCB设计、芯片粘接、优化引线键合参数方面对SOI像素探测器的cob组装工艺做了初步研究。基板焊盘表面处理选用了电镀化学镍钯金的工艺,并对焊盘排布方式做了改进;芯片粘接选用了导电环氧树脂胶,探讨了水平定位误差和垂直定位误差... 详细信息

从子板PCB设计、芯片粘接、优化引线键合参数方面对SOI像素探测器的cob组装工艺做了初步研究。基板焊盘表面处理选用了电镀化学镍钯金的工艺,并对焊盘排布方式做了改进;芯片粘接选用了导电环氧树脂胶,探讨了水平定位误差和垂直定位误差对键合的影响及处理方法;通过反复试验和不断优化得出一套引线键合优化参数。对子板模块性能测试表明:其噪声和漏电流水平均保持在合理范围。cob组装技术可为后续的硅像素探测器芯片拼接提供技术支撑。

关键词： cob 硅像素探测器 SOI 引线键合

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cob白光LED的光提取效率研究

半导体光电 2015年第5期36卷 753-755页

作者：古志良李炳乾范广涵许毅钦张康赵维李成驰中南大学物理与电子学院长沙410083 广东省工业技术研究院广州510650

针对LED高光效、高显色指数的要求,在分析LED光学性能的基础上,采用板上芯片(cob,Chip on Board)技术研究了表面涂覆硅胶量对cob白光LED的光通量、光效、色温和显色指数的影响,并提出一种高光效、高显色指数、低色温的白光LED封装方案,... 详细信息

针对LED高光效、高显色指数的要求,在分析LED光学性能的基础上,采用板上芯片(cob,Chip on Board)技术研究了表面涂覆硅胶量对cob白光LED的光通量、光效、色温和显色指数的影响,并提出一种高光效、高显色指数、低色温的白光LED封装方案,提高了cob白光LED的出光效率,实现了特定的光学分布,最终实现14W cob封装结构下的白光LED,在电流密度为30A/cm2时,其色温、显色指数及光效分别为4 900K、82和125lm/W。

关键词： LED cob 硅胶量高光效高显色指数

Effect of Varying Corn cob and Rice Husk Ashes on Properties of Moulding Sand

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Journal of Minerals and Materials Characterization and Engineering 2011年第15期10卷 1449-1455页

作者： Sunday Aribo Department of Metallurgical and Materials Engineering Federal University of Technology PMB 704 Akure Nigeria

The use of rice husk and corn cob ashes as aggregates for foundry moulding sand has been studied. 5-12.5 weight percent of rice husk and corn cob ashes were added to the sand mixture and the sand properties determined. A mixture of equal proportion of rice husk and corn cob ashes was also used. In each case, four weight percent water and clay were added to the sand mixture. Some of the properties of the sand tested are: permeability, green compression strength, dry compression strength, green shear strength, dry shear strength, moisture content and permeability. The results showed that the green compression strength, green shear strength, moisture content and permeability decrease with increase in the additives (rice husk ash, corn cob ash, and (50% rice husk and 50% corn cob ashes). While dry compression strength and dry shear strength increase with increase in weight percent of the additives.

关键词： moulding sand rice husk corn cob ashes sand properties.

阵列式微型透镜封装多芯片cob LED的光学仿真设计及应用

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应用光学 2014年第6期35卷 1063-1068页

作者：林丞厦门大学物理学博士后流动站福建厦门361005 厦门华联电子有限公司福建厦门361006

为了提高cob LED的取光率,以1919cob LED为研究对象,建立阵列式圆锥透镜、半椭球透镜、四棱锥透镜和半圆球透镜封装LED模型,并利用光学仿真软件进行研究。仿真实验结果表明:在优化条件下,高0.5mm、直径0.9mm的阵列圆锥透镜封装LED的光... 详细信息

为了提高cob LED的取光率,以1919cob LED为研究对象,建立阵列式圆锥透镜、半椭球透镜、四棱锥透镜和半圆球透镜封装LED模型,并利用光学仿真软件进行研究。仿真实验结果表明:在优化条件下,高0.5mm、直径0.9mm的阵列圆锥透镜封装LED的光通量由平面封装的67lm提高至84.3lm,即取光率提高25.8%。制作了RGB芯片的多芯片LED样品,并用直径1mm的阵列半圆球透镜进行封装,其取光率提高18.8%。

关键词：阵列式透镜 cob 光学仿真 LED封装取光率

Performance Evaluation of a Maize cob Thresher

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Journal of Agricultural Science and Technology(A) 2019年第1期9卷 64-70页

作者： Adeyi Abdulrasaq Mashood Willoughby Fouad Ayinde Shehu Muhammed Yusuf Ola Olalekan Abiola Faleye Tope National Centre for Agricultural Mechanization(NCAM) Farm Power&Machinery DepartmentKM 20Ilorin-Lokoja High Way IdofianP.M.B.1525Ilorin Kwara StateNigeria

Threshing is one of the most critical parts of post-harvest operation which affects the quality and quantity of maize *** could be done manually or ***,the objective of this study was to evaluate the performance of a maize cob thresher fabricated at National Centre for Agricultural Mechanization(NCAM)Ilorin at three different moisture contents and analyze the result using ANOVA and bar chart as statistical *** average values of parameters evaluated at three different stages of moisture content(15.81%,16.79%and 17.10%)of maize cob are as follow:threshing capacity 754.20,737.38 and 720.23 kg/h;threshing efficiency 99.73%,99.63%and 99.16%;cleaning efficiency 89.82%,89.45%and 88.34%;broken grains ratio 0.84%,0.79%and 0.70%;time taken 43,44 and 45 s,*** total amount of maize cob fed into the machine was 9 kg in three replicates for each of the moisture content and the average values of threshed maize of 8.08,8.05 and 7.95 kg was recovered,*** was significant difference in threshing efficiency,amount of chaffs in the threshed maize and the percentage broken *** 17.10%moisture content,the percentage broken grain ratio was *** high moisture content,more force,energy and time is required to thresh certain amount of maize ***,at minimal moisture content less force and energy is required for maximum ***,considering the previous work on performance evaluation of maize cob thresher,this machine performed satisfactorily and is far better than manual *** machine is effective,efficient,affordable and available for the small and medium scale farmers in Nigeria.

关键词： Maize cob thresher performance evaluation moisture