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用以区分风成噪声与航船噪声特性的分析技术

声学技术 1976年第2期 27-32页

作者： Anthony j.Perrone louis A.King 杭汝衡

描述了一种在感兴趣的海区中对环境噪声源(风成噪声与航船噪声)予以分类的分析技术,这时并不需要涉及该处环境的或船舶航行的情报。对于一个指定的地理区域,通过长期的环境噪声观察(两星期以上)找出自相关函数的过零点时间与环境噪声时... 详细信息

描述了一种在感兴趣的海区中对环境噪声源(风成噪声与航船噪声)予以分类的分析技术,这时并不需要涉及该处环境的或船舶航行的情报。对于一个指定的地理区域,通过长期的环境噪声观察(两星期以上)找出自相关函数的过零点时间与环境噪声时间系列的频率之关系,就能对风成噪声与航船噪声、或两者的组合予以分类。从噪声级时间系列中获得的自相关函数(用无方向性水听器测量和通过1/3倍频程滤波器处理。)过零点时间的结果表明,它是限制于两个特殊过零点时间界限之内的。从四个相隔很远的地理区域之数据来分析,产生相同的界限值,这就意味着它们与海区无关。在1/3倍频程带宽下与风速有强相关的那一段谱内发现解相关时间(即过零点时间的范围)为26到40小时。在与风速无关的谱段内,就认为是由航船所引起的,它的解相关时间范围为4到8小时。对于由两种噪声组成的谱来说,解相关时间在8到26小时之间。所观察到的相关函数可用一个二项式来近似表达,这有助于在风成噪声级与航船噪声级之比为任何值之下来确定解相关时间。公式的每一项(一是与风速有关,而另一则与航船有关)都是正弦形式。它们的衰减参量等于它的相应的解相关时间平均值,正弦周期则为此值的四倍。

关键词：噪声级百慕大过零点海盆噪声源洋盆盆地自相关函数噪声比等效输入噪声级分析技术

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逼真动物素描技巧

Study of the Relative Variations of the Thermal Properties and Crystallinity of Blends (PP/EPR)/Calcium Carbonate

2016年

作者： (美)罗伯特·路易斯·考德威尔

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Modeling and Numerical Simulation of Material Science 2021年第1期11卷 19-33页

作者： Pierre Marcel Anicet Noah Fabien Betene Ebanda louis-Max Ayina Ohandja Ateba Atangana Laboratory of Mechanics ENSET University of Douala Douala Cameroon Department of Mechanical Engineering ENSET University of Douala Douala Cameroon

The objective of this paper is to investigate the relative variations of the constants of the thermal properties and the degree of crystallinity of the mixtures (PP/EPR)/Calcium carbonates elaborated with the Micro Bivis. We have strengthened the basic copolymer PP/EPR of a low level (5%) by three calcium carbonates models socal312, socal322v, Winnofil spm. We then subjected the different mixtures obtained, two cycles of a thermal loading under differential scanning calorimetry DSC. We finally focused on the thermal properties of isotactic polypropylene (TfP, TcP, ΔHfP, ΔHcP) and we calculated the degree of crystallinity of the mixtures. Reducing the energy cost of implementing mixtures is one of the objectives of this work. We quantified the relative variations of the above properties with those of the base copolymer. It shows that at a low loading rate of calcium carbonate, there is a decrease in the enthalpies of crystallization during the second exothermic cycle, with values that can reach 5.53 j/gPP for the basic copolymer PP/EPR. During the second endothermic cycle, there is an overall increase in isotactic polypropylene melting temperature values for all the blends as well as for the basic copolymer PP/EPR. There is evidence that calcium carbonates are useful for lowering the melting energy of isotactic polypropylene, even at a low loading rate for the majority. The number of endothermic cycles accentuates this phenomenon which is linked to the presence in our composites, of a so-called confined amorphous phase.

关键词： DSC PP/EPR CaCO3 Crystallinity Micro Bivis

Orchestration of occludins, claudins, catenins and cadherins as players involved in maintenance of the blood-epididymal barrier in animals and humans

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Asian journal of Andrology 2007年第4期9卷 463-475页

作者： Daniel G. Cyr Mary Gregory Evemie Dube julie Dufresne Peter T. K. Chan louis Hermo INRS-Institut Armand Frappier Universite du Quebec 245 Hymus Boulevard Pointe Claire QC H9R 1G6 Canada Department of Urology Royal Victoria Hospital McGill University Montreal QC H3A 1A1 Canada Department of Anatomy and Cell Biology McGill University Montreal QC H3A 2B2 Canada

Although spermatozoa are formed during spermatogenesis in the testis, testicular spermatozoa are immature and cannot swim or fertilize. These critical spermatozoal functions are acquired in the epididymis where a specific luminal environment is created by the blood-epididymal barrier; proteins secreted by epididymal principal cells bind to maturing spermatozoa and regulate the maturational process of the spermatozoa. In the epididymis, epithelial cell-cell interactions are mediated by adhering junctions, necessary for cell adhesion, and by tight junctions, which form the blood-epididymal barrier. The regulation of these cellular junctions is thought to represent a key determinant in the process of sperm maturation within the epididymis. Tight junctions between adjacent principal cells permit the formation of a specific microenvironment in the lumen of the epididymis that is essential for sperm maturation. Although we have made significant progress in understanding epididymal function and the blood-epididymal barrier, using animal models, there is limited information on the human epididymis. If we are to understand the normal and pathological conditions attributable to human epididymal function, we must clearly establish the physiological, cellular and molecular regulation of the human epididymis, develop tools to characterize these functions and develop clinical strategies that will use epididymal functions to improve treatment of infertility. （Asian j Androl 2007 july; 9： 463- 475）

关键词： claudins cadherins catenins human rat mouse tight junction adherens junction

Global wild rice germplasm resources conservation alliance:World Wild-Rice Wiring

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Molecular Plant 2024年第4期17卷 516-518页

作者： Xiaoming Zheng Disna Ratnasekera jiayu Fan Robert j.Henry Beng-Kah Song Kenneth M.Olsen Bal Krishna joshi Maria Celeste N.Banaticla-Hilario Tonapha Pusadee Adane Getachew Melaku Yeyinou Laura Estelle Loko Koukham Vilayheuang Gavers K.Oppong Samuel Aduse Poku Peterson W.Wambugu Song Ge Aldo Merotto junior Ohn Mar Aung Ramaiah Venuprasad Ajay Kohli Wenbin Zhou Qian Qian National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Sanya National Research Institute of Breeding in Hainan Chinese Academy of Agricultural SciencesBeijing 100081China International Rice Research Institute DAPO Box 7777Metro Manila 4031Philippines Department of Agricultural Biology Faculty of AgricultureUniversity of RuhunaMatara 81000Sri Lanka Yazhouwan National Laboratory No.8 Huanjin RoadYazhou DistrictSanya CityHainan Province 572024China Hainan University Haikou 570228China ARC Centre of Excellence for Plant Success in Nature and Agriculture University of QueenslandBrisbaneQLD4072Australia School of Science Monash University Malaysia47500 Bandar SunwaySelangor 47500Malaysia Department of Biology Washington University in St.LouisSt.LouisMO 63130-4899USA National Agriculture Genetic Resources Center(Genebank) KhumaltarPO Box 3055KathmanduNepal Plant Biology Division Insttute of Biological SciencesUniversity of the Pilippines Los BanosLos BanosLaguna 4031Philippines Division of Agronomy Department of Plant and Soil SciencesFaculty of AgricultureChiang Mai UniversityChiang Mai 50200Thailand Bio and Emerging Technology Institute Addis Ababa 1165Ethiopia National University of Sciences TechnologiesEngineering and Mathematics(UNSTIM)Dassa-ZouméBP 14Benin National Genebank Rice and Cash Crops Research CenterNAFRIVientiane 0605Lao PDR Plant Sciences and the Bioeconomy Rothamsted ResearchHarpenden AL52JQUK UK Future Food Beacon of Excellence and School of Biosciences and University of Nottingham Nottingham LE125RDUK Department of Plant and Environmental Biology University of GhanaAccraGhana Kenya Agricultural and Livestock Research Organization Genetic Resources Research InstituteNairobi 00200Kenya Institute of Botany Chinese Academy of SciencesBeijing 100093China Federal University of Rio Grande do Sul UFRGSPorto Alegre 91501-970RSBrazil Department of Agricultur

Wild relatives of crop are key genetic resources serving as diversity reservoirs for crop improvement under changing ***(Oryza sativa)is one of the most important crops in the world,providing staple food for half of the world's *** rice is thus a critical germplasm resource for sustained global food security,ensuring high production yields,improved quality,and stress resistance in the face of climate *** rice is closely related to domesticated rice and has a rich genetic diversity and exceptional adaptability to extreme *** has played a pivotal role in the history of rice hybridization and has become a key resource for rice breeding *** identification of wild-type cytoplasmic male sterility resources paved the way for the achievement of the“three lines”goal in hybrid rice,leading to a significant increase in rice *** addition,the use of resistance alleles found in wild rice is making rice production more resilient to losses caused by environmental ***,wild rice germplasm resources are threatened due to habitat destruction and other anthropogenic *** the same time,the lack of centralized distribution of wild rice has hampered the sharing of basic information on wild rice resources and the utilization and conservation of wild rice in each country,as well as collaboration among scientists.

关键词： germplasm breeding crops

晃动液体在加速度突然减小时的行为的实验研究

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导弹与航天运载技术(中英文) 1979年第10期 59-89页

作者： louis E.Toole Leon j.Hastings 应桂炉

对以基本反对称振型振动的液柱在轴向加速度突然减小时的行为作了实验研究。为了得到时间最长为4.3秒的可控制低重力环境,采用了马歇尔宇宙飞行中心的落塔设备。试验在直径为6吋的圆柱形贮箱内进行,试验液体为石油醚,其接触角为零。试验... 详细信息

对以基本反对称振型振动的液柱在轴向加速度突然减小时的行为作了实验研究。为了得到时间最长为4.3秒的可控制低重力环境,采用了马歇尔宇宙飞行中心的落塔设备。试验在直径为6吋的圆柱形贮箱内进行,试验液体为石油醚,其接触角为零。试验的Bond数和Froude数变化范围(基于半径R)分别为12～100和0.03～22。得到了在推进剂控制系统设计中普遍适用的工程结果。同时,对于特定的S-ⅣB-203几何形状(带与不带防晃板和导流器)和入轨时的能量条件下的液体行为进行了估计。结果表明,在Fr=0.03～14.6和B0=24～100范围内,最大液体振幅唯一依赖于Froude数。模拟不带防晃板的S-ⅣB-203液氢能量条件(Fr=19.3)产生晃动振幅放大,致使在低重力环境下有连续两个波达到S-ⅣB液氢箱模型的前底顶部。位于液面或稍高于液面的环形防晃板在减小晃动放大和阻尼低重力下的液体晃动都是很有效的。液体在S-ⅣB-203模型试验中的行为与AS-203入轨后观察到的非常相似。低重力环境下液体粘性对振动的衰减作用用对数衰减率描述,当初始振幅从0.6R至1.05R变化时,发现对数衰减率与振幅有关,随振幅增加而增加。大振幅晃动的初始阻尼比适用的关系式所预示的要大得多。液柱振动频率随所作用的加速度的变化而瞬时改变。加速度减小后第一周运动的周期测定值与Satterlee-Reynolds方程一致,在所试验的Bond数范围内相差不到8％。对于液体深度大于或等于R的情况,推导了液体重心最大移动量的经验关系式,它是Froude数的函数。

关键词：防晃板导流器液位能量条件推进剂控制贮箱加速度运动学

高速水流喷射冲击点焊——在太空中实现薄板冲击点焊的装置

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焊接学报 1982年第1期 10-12+56-57页

作者： F.Erdmann-jesnitzer,H.louis,j.Wiedemeier 西德汉诺威大学西德汉诺威大学西德汉诺威大学

在太空中的焊接有可能成为修复太阳能电池板的好方法。本文介绍一种用水流(或其它液体)喷射冲击点焊的方法。采用这种方法可以得到具有高强度的环形焊接区。为了产生高速流体喷射,设计、制造了一套尺寸较小的专用系统。这样就使得利用... 详细信息

在太空中的焊接有可能成为修复太阳能电池板的好方法。本文介绍一种用水流(或其它液体)喷射冲击点焊的方法。采用这种方法可以得到具有高强度的环形焊接区。为了产生高速流体喷射,设计、制造了一套尺寸较小的专用系统。这样就使得利用流体喷射冲击实现在太空中焊接薄板的设想成为可能。

关键词：点焊电阻焊喷射冲击薄板装置

REITERATED HOMOGENIZATION OF DEGENERATE NONLINEAR ELLIPTIC EQUATIONS

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Chinese Annals of Mathematics,Series B 2002年第3期23卷 325-334页

作者： j.BYSTRM j.ENGSTRM P.WALL Dedicated to the memory of jacques-louis Lions Dedicated to the memory of Jacques-Louis LionsDedicated to the memory of Jacques-Louis Lions

The authors study homogenization of some nonlinear partial differential equations of the form -div (?(hx, h2x,Duh)) =f, where a is periodic in the first two arguments and monotone in the third. In particular the case where a satisfies degenerated structure conditions is studied. It is proved that uh converges weakly in W01,1 (?) to the unique solution of a limit problem as h ? '. Moreover, explicit expressions for the limit problem are obtained.

关键词： Homogenization Reiterated Monotone Degenerated

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Physicians’ Use of Patients’ Daily Reports of Quality of Life to Evaluate Treatment Response in Phase I Cancer Trials

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journal of Cancer Therapy 2012年第5期3卷 582-588页

作者： Felicity W. K. Harper Elisabeth I. Heath Marci E. j. Gleason louis Penner Patricia LoRusso Ding Wang Terrance L. Albrecht josephine Ford Cancer Center at Henry Ford Hospital Detroit USA Karmanos Cancer Institute Communication and Behavioral Oncology Program Detroit USA University of Texas Department of Human Ecology Austin USA 4josephine Ford Cancer Center at Henry Ford Hospital Detroit USA

For cancer patients on Phase I trials, one of the most important physician decisions is whether or not patients are deriving benefit from therapy. With an increasing number of cytostatic treatment agents, the criteria to determine patient response to Phase I treatment has become harder to define. Physicians are increasingly looking to patient-reported outcomes (PROs) such as quality of life (QOL) to help evaluate treatment response. Electronic daily diary (EDD) devices can be used by patients to report their QOL over extended periods of time, thereby providing a more accurate picture of how patients are affected by treatment on a daily basis. However, questions remain about how to integrate this patient-reported information into decisions about Phase I treatment. This study investigated how physicians use patients’ daily QOL reports to evaluate patient response to Phase I treatment. Data were collected over a 4-month period from Phase I patients (N = 30) and physicians (N = 3) in an NCI-designated comprehensive cancer center. Patients completed daily QOL reports using EDD devices and physicians were provided with a summary of patients’ QOL before each visit. After the visit, doctors recorded their treatment decision and also rated the importance of four biomedical factors (Toxicity, Imaging, Labs, and Performance Status) and QOL in their treatment decision for that visit. Although physicians rated QOL as being very important in evaluating treatment response, in practice, when predictors of their decisions were analyzed, results showed they relied exclusively on biomedical data (Toxicity, Imaging) to make Phase I treatment decisions. Questions remain about the utility and effective integration of QOL and biomedical data in clinical decision-making processes in Phase I clinical trials.

关键词： Patient-Reported Outcomes Quality of Life Clinical Trials Treatment Decision-Making