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空中英语教室（高级版．彭蒙惠英语） 2011年第5期 28-29,45页

作者： Paul davidson

Gas flow in rotary kilns

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Particuology 2010年第6期8卷 613-616页

作者： Patrick R.Davies Michael J.S.Norton D.Ian Wilson John F.davidson David M.Scott Department of Chemical Engineering and Biotechnology University of CambridgePembroke StreetCambridgeCB2 3RAUK

This paper describes an experimental investigation on the flow characteristics within a rotating cylinder containing a rolling bed of sand. The axis of the cylinder was horizontal and there was no axial bulk flow of particles. The velocity field of the gas flowing through the cylinder was measured by hot-wire anemometry. The measurements indicate that the velocity field is asymmetric with respect to a diameter perpendicular to the granular bed. CFD calculations confirm this finding. The gas velocity profiles are crucial in determining heat transfer from gas to solid.

关键词： Rotating cylinderVelocity profile

Glia and hemichannels: key mediators of perinatal encephalopathy

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Neural Regeneration Research 2018年第2期13卷 181-189页

作者： Robert Galinsky Joanne O.davidson Justin M.Dean Colin R.Green Laura Bennet Alistair J.Gunn Department of Physiology University of Auckland The Ritchie Centre Hudson Institute of Medical Research Department of Ophthalmology University of Auckland

Perinatal encephalopathy remains a major cause of disability, such as cerebral palsy. Therapeutic hypo- thermia is now well established to partially reduce risk of disability in late preterm/term infants. However, new and complementary therapeutic targets are needed to further improve outcomes. There is increasing evidence that glia play a key role in neural damage after hypoxia-ischemia and infection/inflammation. In this review, we discuss the role of astrocytic gap junction （connexin） hemichannels in the spread of neural injury after hypoxia-ischemia and/or infection/inflammation. Potential mechanisms of hemichannel medi- ated injury likely involve impaired intraceUular calcium handling, loss of blood-brain barrier integrity and release of adenosine triphosphate （ATP） resulting in over-activation of purinergic receptors. We propose the hypothesis that inflammation-induced opening of connexin hemichannels is a key regulating event that initiates a vicious cycle of excessive ATP release, which in turn propagates activation of purinergic receptors on microglia and astrocytes. This suggests that developing new neuroprotective strategies for preterm infants will benefit from a detailed understanding of glial and connexin hemichannel responses.

关键词： hypoxia-ischemia connexin hemichannels spreading injury connexin 43 astrocytes hypoxicischemic encephalopathy

After the fact : 5th ed.

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NATURAL PRODUCTIVITY OF ACRYLIC ACID AND DIMETHYL SULPHIDE DURING A SUMMER BLOOM OF PHAEOCYSTIS POUCHETII IN ANTARCTIC COASTAL WATER

2005年

作者： davidson James West.Lytle Mark H.

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Chinese Journal of Polar Science 1992年第1期3卷 31-39页

作者： Andrew davidson Harry Burton Anstralia Antarctic Division Channel Highway Kingston Tasmania 7050Anstralia Antarctic Division Channel Highway Kingston Tasmania 7050

Water samples were collected over P. ponchetii bloom period beginning in November 1988, in 15m water column, from 10km offshore of Davis Station, Vestfold Hill, Antarctica. The concentrations of acrylic acid and dimethyl sulphide (DMS), which are toxic compounds in the water samples, were determined by HPLC and GC. The result shows that the concentration of acrylic acid varies in 0. 001 - 0. 510μmol ?L-1 and the concentration of DMS in 0. 003-0. 588 μmol ?L-1 during P. pouchetii bloom. Both the increased since late December 1988 and reached the highest concentration in early January 1989, then they decreased rapidly and returned to lower level from middle January to February in agreement with variation in cell number of the unicell alga P. pouchetii. The correlation coefficients between acrylic acid and P. pouchetii and between DMS and P. pouchetii are all 0. 998. It is undoubted that P. pouchetii produced acrylic acid and DMS. The highest productivity of acrylic acid and DMS were 9. 76X 10-8 umol cell-1 and 13. 09 ×10-8 μmol ?cell-1, respectively, during P. pouchelii bloom. A cellular product, dimethylsulphonium propionate (DMSP), is decomposed into acrylic acid and DMS, and the formation of DMSP is probably from methionine which could be utilized by P. pouchelii.

关键词： Antarctica acrylic acid DMS proud uctivity P. pouchetii.

Power System Modelling and Fault Analysis of NamPower＇s 330 kV HVAC Transmission Line

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Journal of Energy and Power Engineering 2014年第8期8卷 1432-1442页

作者： Innocent davidson Immanuel Mbangula HVDC/Smart Grid Research Centre University of KwaZulu-Natal Durban 4041 South Africa

Electric power systems usually cover large geographical areas and transmission facilities are continuously increasing. These power systems are exposed to different environmental conditions which may cause faults to occur on the system. Different types of studies are usually done on electric power systems to determine how the system behaves before, during and after a fault condition. The behaviour of variables of interest such as currents, voltage, rotor angle and active and reactive power under fault conditions are studied and observed to help determine possible causes of faults in a power system. The objective of this paper is to investigate a fault that occurred on the 330 kV transmission line between Ruacana power station and Omburu sub-station, the fault caused all the generators at Ruacana power station to trip and consequently caused a blackout at the power station that lasted for 6 h. Preliminary findings showed that the observed fault was an earth fault but the exact type of earth fault was however not known at the time. This research investigation sets out to determine the exact fault that occurred; the most probable cause of the fault, and propose possible solutions to prevent reoccurrence of such a fault. The section of the power network in which the fault occurred was modelled using DigSilent Power Factory software tool, and transient fault analysis was carried out on the model for different fault conditions. Results obtained were then compared with data obtained from NamPower records to ascertain the type of fault.

关键词： Fault analysis power system transient stability

弧线段T-Map布尔交运算获取线轮廓度T-Map的方法研究（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2015年第5期16卷 341-352页

作者： Yifei HE Joseph K.davidson Jami J.SHAH Siemens PLM Software Inc.2000 Eastman DriveMilfordOhio 45150USA Mechanical & Aerospace Engineering Arizona State University

目的:为使零件在设计阶段实现公差的自动分配,研究线轮廓度在计算机中的表达模型。创新点:1.提出一种新的构建线轮廓度公差T-Map图的方法;2.用运动学等效的方法表示理想轮廓公差域的允许偏差。方法:1.将零件轮廓分解成多段,然后分别为... 详细信息

目的:为使零件在设计阶段实现公差的自动分配,研究线轮廓度在计算机中的表达模型。创新点:1.提出一种新的构建线轮廓度公差T-Map图的方法;2.用运动学等效的方法表示理想轮廓公差域的允许偏差。方法:1.将零件轮廓分解成多段,然后分别为每段生成一个实体模型T-Map(图6和7);2.利用布尔交运算将所有分段T-Map合成一个完整线轮廓度的T-Map(图8);3.以弧形短槽为例,演示创建线轮廓度的方法步骤。结论:将弧形短槽轮廓分成多段,先实现每一段的T-Map,再利用布尔交实现整体线轮廓度公差的T-Map图,证明该方法在构建任意轮廓的线轮廓度公差上的有效性。

关键词：几何公差线轮廓度公差模型公差带布尔交

C++ Program Design an introduction to programming and Object-Oriented Design 2nd ed

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1999年

作者： James P. Cohoon Jack W. davidson.

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土地资源评价信息系统——以延安地区为例

水土保持学报 1989年第1期3卷 1-9页

作者：傅伯杰 Donald A. davidson 北京大学地理系英国Stirling大学环境科学系

土地资源信息系统是在计算机软硬件支撑下,将土地空间信息以一定格式输入、存贮、检索、显示和综合分析应用的技术系统。它是土地评价、土地规划和土地管理的强有力工具。本文以延安地区为例,运用网格数据格式,建立了土地资源评价信息系... 详细信息

土地资源信息系统是在计算机软硬件支撑下,将土地空间信息以一定格式输入、存贮、检索、显示和综合分析应用的技术系统。它是土地评价、土地规划和土地管理的强有力工具。本文以延安地区为例,运用网格数据格式,建立了土地资源评价信息系统,完成了农业、林业、牧业土地评价,为区域土地利用规划和合理利用土地提供了科学依据。

关键词：土地资源信息系统计算机制图系统要素图土地资源评价土地评价土地利用规划土地规划延安陕西

Posterior interosseous nerve localization within the proximal forearm-a patient normalized parameter

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World Journal of Orthopedics 2017年第4期8卷 310-316页

作者： Srinath Kamineni Crystal R Norgren Evan M davidson Ellora P Kamineni Andrew S Deane Elbow Shoulder Research Centre Depart-ment of Orthopaedics and Sports MedicineUniversity of Kentucky University of Kentucky College of Medicine Paul Laurence Dunbar High School Department of Anatomy and Cell Biology Indiana University School of Medicine

AIM To provide a "patient-normalized" parameter in the proximal forearm. METHODS Sixty-three cadaveric upper extremities from thirty-five cadavers were studied. A muscle splitting approach was utilized to locate the posterior interosseous nerve(PIN) at the point where it emerges from beneath the supinator. The supinator was carefully incised to expose the midpoint length of the nerve as it passes into the forearm while preserving the associated fascial connections, thereby preserving the relationship of the nerve with the muscle. We measured the transepicondylar distance(TED), PIN distance in the forearm's neutral rotation position, pronation position, supination position, and the nerve width. Two individuals performed measurements using a digital caliper with inter-observer and intraobserver blinding. The results were analyzed with the Wilcoxon-Mann-Whitney test for paired samples. RESULTS In pronation, the PIN was within two confidence intervals of 1.0 TED in 95% of cases(range 0.7-1.3 TED); in neutral, within two confidence intervals of 0.84 TED in 95% of cases(range 0.5-1.1 TED); in supination,within two confidence intervals of 0.72 TED in 95% of cases(range 0.5-0.9 TED). The mean PIN distance from the lateral epicondyle was 100% of TED in a pronated forearm, 84% in neutral, and 72% in supination. Predictive accuracy was highest in supination; in all cases the majority of specimens(90.47%-95.23%) are within 2 cm of the forearm position-specific percentage of TED. When comparing right to left sides for TEDs with the signed Wilcoxon-Mann-Whitney test for paired samples as well as a significance test(with normal distribution), the P-value was 0.0357(significance-0.05) indicating a significant difference between the two *** This "patient normalized" parameter localizes the PIN crossing a line drawn between the lateral epicondyle and the radial styloid. Accurate PIN localization will aid in diagnosis, injections, and surgical approaches.

关键词： Posterior interosseous nerve Radial nerve Transepicondylar distance Radial tunnel syndrome Supinator syndrome