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Review of fast methods for point-based computer-generated holography [Invited]

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Photonics Research 2018年第9期6卷 837-846页

作者： P.W.M.tSANG t.-C.POON Y.M.WU Department of Electronic Engineering City University of Hong Kong Bradley Department of Electrical and Computer Engineering Virginia Tech

Computer-generated holography(CGH) is a technique for converting a three-dimensional(3D) object scene into a two-dimensional(2D), complex-valued hologram. One of the major bottlenecks of CGH is the intensive computation that is involved in the hologram generation process. to overcome this problem, numerous research works have been conducted with the aim of reducing arithmetic operations involved in CGH. In this paper,we shall review a number of fast CGH methods that have been developed in the past decade. these methods,which are commonly referred to as point-based CGH, are applied to compute digital Fresnel holograms for an object space that is represented in a point cloud model. While each method has its own strength and weakness,trading off conflicting issues, such as computation efficiency and memory requirement, they also exhibit potential grounds of synergy. We hope that this paper will bring out the essence of each method and provide some insight on how different methods may crossover into better ones.

关键词：全息术计算机技术发展现状三维技术

Feasibility of developing composite action between concrete and cold-formed steel beam

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Journal of Central South University 2013年第12期20卷 3689-3696页

作者： S.O.Bamaga M.Md.tahir t.C.tan S.Mohammad N.Yahya A.L.Saleh M.Mustaffar M.H.Osman A.B.A.Rahman Construction Research Centre (UtM-CRC) Faculty of Civil EngineeringUniversiti Teknologi Malaysia

Cold-formed steel structures are steel structure products constructed from sheets or coils using cold rolling, press brake or bending brake method. these structures are extensively employed in building construction industry due to their light mass, ductility by economic cold forming operations, favorable strength-to-mass ratio and other factors. the utilization of cold formed steel sections with concrete as composite can hugely reduce the construction cost. However, the use of cold formed steel members in composite concrete beams has been very limited. A comprehensive review of developments in composite beam with cold formed steel sections was introduced. It was revealed that employing cold-formed steel channel section to replace reinforcement bars in conventional reinforced concrete beam results in a significant cost reduction without reducing strength capacity. the use of composite beam consisting of cold-formed steel open or close box and filled concrete could also reduce construction cost. Lighter composite girder for bridges with cold-formed steel of U section was introduced. Moreover, types of shear connectors to provide composite action between cold-formed steel beam and concrete slab were presented. However, further studies to investigate the effects of metal decking on the behavior of composite beam with cold-formed steel section and introduction of ductile shear connectors were recommended.

关键词： cold formed steel beam composite shear connection thin-wall composite girder

过度通气能够改善幕上开颅术的手术条件吗？一项多中心随机交叉试验研究

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麻醉与镇痛 2009年第3期5卷 17-27页

作者： adrian W. Gelb Rosemary A. Craen G. S. Umamaheswara Rao K. R. Madhusudan Reddy Joseph Megyesi Bibek Mohanty Hari H. Dash Kai C. Choi Mathew t.V. Chan 谢珺田(译) Department of Anesthesia and Perioperative Care University of California at San Francisco San Francisco California Department of Anesthesia and Perioperative Medicine University of Western Ontario Canada Departments of Anesthesia and Neuroanaesthesia National Institute of Mental Health and Neurosdences Bangalore India Department of Neurosurgery University of Western Ontario Canada Department of Neuroanesthesiology All India Institute of Medical Sdences Delhi India Centre for Epidemiology and Biostatistics The Chinese University of Hong Kong Hong Kong Spedal Administrative Region Department of Anaesthesia and Intensive Care CUHK Brain Tumor Center The Chinese University of Hong Kong Prince of Wales Hospital Hong Kong Special Administrative Region 不详

背景过度通气作为神经外科手术麻醉中的重要方法，其有效性还缺乏验证。我们在由手术医师评估脑肿胀分级和测定颅内压（ICP）的条件下，选择中度低碳酸血症和正常血液碳酸数值两种情况对接受开颅手术的幕上脑肿瘤患者进行一项双周期随... 详细信息

背景过度通气作为神经外科手术麻醉中的重要方法，其有效性还缺乏验证。我们在由手术医师评估脑肿胀分级和测定颅内压（ICP）的条件下，选择中度低碳酸血症和正常血液碳酸数值两种情况对接受开颅手术的幕上脑肿瘤患者进行一项双周期随机交叉试验研究。方法275例幕上脑肿瘤患者随机接受以下治疗程序：一是过度通气（动脉二氧化碳分压，PaCO2=25±2mmHg）继以正常通气（动脉二氧化碳分压，PaCO2=37±2mmHg）；二是正常通气继以过度通气。通气和呼气末CO2分压保持稳定20分钟。患者随机接受丙泊酚输注或异氟烷吸入麻醉。在每一试验阶段末由不了解治疗程序的手术医师测定ICP，并以4级评定方法评估脑肿胀分级。结果以通用估计方程模型分析，我们发现过度通气降低了45％脑肿胀加重的风险，P=0．004，95％可信区间为22％-61％，需要治疗患者数为8。过度通气期间ICP均数±标准差为12．3±8．1mmHg，低于正常通气时的16．2±9．6mmHg，P〈0．001。麻醉方式对脑肿胀评估和ICP无影响。结论对幕上脑肿瘤患者而言，手术中过度通气可改善与ICP降低相关的由手术医师评估的脑肿胀程度。

关键词：试验研究随机手术条件动脉二氧化碳分压开颅术多中心呼气末CO2分压过度通气

Zonal aspects of the influence of forest cover change on runoff in northern river basins of Central Siberia

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Forest Ecosystems 2021年第3期8卷 602-614页

作者： A.Onuchin Т.Burenina А.Shvidenko D.Prysov A.Musokhranova V.N.Sukachev Institute of Forest Siberian Branch of the Russian Academy of Sciences 660036Academgorodok50/28Russia 31KrasnoyarskRussia International Institute for Applied Systems Analysis A-2361 LaxenburgAustria

Background:Assessment of the reasons for the ambiguous influence of forests on the structure of the water balance is the subject of heated debate among forest *** the components of total evaporation,forest vegetation makes a significant contribution to the process of runoff formation,but this process has specific features in different geographical *** issues of the influence of forest vegetation on river runoff in the zonal aspect have not been sufficiently ***:Based on the analysis of the dependence of river runoff on forest cover,using the example of nine catchments located in the forest-tundra,northern and middle taiga of Northern Eurasia,it is shown that the share of forest cover in the total catchment area(percentage of forest cover,FCP)has different effects on runoff *** experiments with the developed empirical models have shown that an increase in forest cover in the catchment area in northern latitudes contributes to an increase in runoff,while in the southern direction(in the middle taiga)extensive woody cover of catchments“works”to reduce *** effectiveness of geographical zonality in regards to the influence of forests on runoff is more pronounced in the forest-tundra zone than in the zones of northern and middle ***:the study of this problem allowed us to analyze various aspects of the hydrological role of forests,and to show that forest ecosystems,depending on environmental conditions and the spatial distribution of forest cover,can transform water regimes in different *** the fact that the process of river runoff formation is controlled by many factors,such as temperature conditions,precipitation regime,geomorphology and the presence of permafrost,the models obtained allow us to reveal general trends in the dependence of the annual river runoff on the percentage of forest cover,at the level of *** results obtained are consistent with the concept of geographic

关键词： River runoff Catchments Forest cover Geographic zoning Central Siberia

Factor Affecting Gel time/Process-Ability of Urea Formaldehyde Resin Based Wood Adhesives

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Open Journal of Polymer Chemistry 2017年第2期7卷 33-42页

作者： Ravindra V. Gadhave Prakash A. Mahanwar Pradeep t. Gadekar Department of Polymer and Surface Engineering Institute of Chemical Technology (ICT) Mumbai India

Urea-formaldehyde (UF) resin presents the most utilized adhesive system in the manufacture of plywood, particleboard and fiberboard. At the temperatures above 100°C in the presence of hardener, this resin undergoes cross-linking reaction and the formation of three dimensional cross linked structures takes place and bonding of wood particles in a hot press [1]. UF powder resins show high reactivity and good performance in the production and by their low price;however they lack in water resistance of the hardened resin [2]. Urea-formaldehyde (UF) resins are the most important type of adhesive resins for the production of wood based panels but process-ability and curing behavior of urea formaldehyde resin depended on various factors related to resin properties, types of wood and their properties, amount & type of catalyst, types and amount of polymers addition and environmental conditions [3]. this factor decides the process-ability of UF resin based composite during manufacturing of plywood, particle board and fiberboard. In this review paper, various factors affecting gel time and process-ability of UF resin based wood composite are reviewed.

关键词： Urea Formaldehyde Resins Catalysts Gel time Wood pH Polyvinyl Acetate Composite

In situ X-ray and tEM Observations on the Phase transitions of BC2N under Static High pressures

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In situ X-ray and TEM Observations on the Phase Transitions ...

中国冬播小麦面粉颗粒度分布及近红外透射光谱测试技术研究

18th International Conference on High pressure Science and technology

作者： Wataru Utsumi S.Nakano K.Kimoto t.Okada M.Isshiki t.taniguchi SPring-8 Japan Atomic Energy Research Institute MikazukiSayoHyogo 679-5148Japan National Institute for Research in Inorganic Materials NamikiTsukubaIbaraki 305-0044Japan SPring-8 Japan Synchrotron Radiation Research Institute MikazukiSayoHyogo 679-5198Japan

Several attempts to synthesize a cubic BCNhave been made by various high pressure/temperaturetechnique,which is a hybrid composite ofdiamond and c-BN and is expected to have manyexcellent *** a large volume press,Nakano et *** a mixed phases of diamond,cBN,cubic-BCN,and graphitic BCN at ***,we report our new experimental results underhigher pressure regions up to 21GPa combined within situ x-ray observation using synchrotron *** situ x-ray observations under high pressuresand temperatures were made using a multi-anvil typehigh-pressure apparaus (SPEED-1500) installed onBL04B1 beamline at the *** BCN,prepared by a vapor-phase reaction ofBCl and CHCN,was used as a starting *** phase transition from graphitic BCN to cubicBCN was clearly confirmed at 1250C (pressure was

关键词： diamond superhard material synchrotron radiation multi-anvil

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作物学报 2005年第3期31卷 302-307页

作者：陈锋 Nagamine t 张艳何中虎王德森 Hisashi Yoshida 中国农业科学院作物育种栽培研究所/国家小麦改良中心北京100081 国际农业谷物育种实验室日本富士7218514 日本国际协力机构中国可持续农业技术研究发展计划日本专家组北京100081

面粉颗粒度是影响小麦食品加工品质的重要性状。以2 0 0 1- 2 0 0 2年度来自北部冬麦区、黄淮冬麦区、长江中下游冬麦区和西南冬麦区的2 5 6份小麦品种(系)为材料,用激光散射颗粒度分析仪和近红外透射光谱技术对面粉颗粒度进行了研究。... 详细信息

面粉颗粒度是影响小麦食品加工品质的重要性状。以2 0 0 1- 2 0 0 2年度来自北部冬麦区、黄淮冬麦区、长江中下游冬麦区和西南冬麦区的2 5 6份小麦品种(系)为材料,用激光散射颗粒度分析仪和近红外透射光谱技术对面粉颗粒度进行了研究。结果表明,我国小麦面粉颗粒度分布特点为从北向南,硬质麦分布比例逐渐减少,软质麦分布比例逐渐增大。总体上硬质麦所占比例较高,为5 9. 4 % ,软质麦和混合麦所占比例分别为2 8 .1%和12 .5 %。近红外预测集模型决定系数为0 92 ,与激光散射颗粒度分析仪测试结果之间呈极显著正相关。在建立模型时,采用预测残差平方和及交叉验证处理方法进行了主成分数目选择,并对定标集样品中浓度超常样品和光谱超常样品做2次删除,删除样品数占总样品数的4 .1% ,使定标模型决定系数RSQ从0 . 82提高到0. 92 ,标准误差SEC从12 . 75下降到8 .5 4 ,提高了模型的预测精度,优化了定标模型。此外,根据我国小麦颗粒度大小分布的特点,建立了各麦区的定标模型,其可靠性优于以总参试样品建立的模型。

关键词：普通小麦面粉颗粒大小近红外光谱技术定标集预测集

Investigation of Mechanical Properties of Nanostructured titanium Processed by Warm ECAP Followed Cold Rolling

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Investigation of Mechanical Properties of Nanostructured Tit...

Effect of Slow Cooling in Reducing Pore Size in a Sintered Powder Metallurgical 6061Aluminium Alloy

the 2012 International Conference on Advanced Material and Manufacturing Science(ICAMMS 2012)

作者： Hai D.V Giang N.t School of Material Science and Engineering Hanoi University of Science and Technology-VIETNAM International Research Center for Computational Materials Science Hanoi University of Science and Technology-VIETNAM

In this work,ECAP technique was combined with cold rolling process in order to enhance mechanical properties and microstructure of pure *** grain（CG） titanium with original grain size of 150 μm had been pressed by ECAP at 425℃ by 4,8 and 12 passes,*** process *** followed by rolling at room temperature with 35%,55%,and 75%rolling *** two steps,mechanical properties such as strength,hardness and microstructure of processed titanium have been *** result indicated significant effect of cold rolling on tensile strength,hardness and microstructure of ECAP-titanium.

关键词： Equal Channel Angular pressing(ECAP) cold rolling(CR) ultrafine-grained(UFG) titanium

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Materials Sciences and Applications 2011年第7期2卷 870-877页

作者： S. Solay Anand B. Mohan t. R. Parthasarathy 不详

the usage of powder metallurgy aluminium compacts in lieu of ferrous components in automotives helps to lower vehicle weight. the major drawback in the commercially available press sintered aluminium alloy is porosity which is mainly dependent on the powder metallurgical process parameters such as compaction pressure, sintering temperature and cooling rate after sintering. In this paper the effect of particle size and furnace controlled cooling after sintering on porosity level and micro hardness of an elemental 6061 aluminium alloy has been investigated. Aluminium particle sizes of 20 μm and 150 μm were used. the elemental 6061 aluminium alloy powders are warm compacted at 175 MPa. After sintering for about one hour at 600°C, the aluminium compacts were furnace cooled at the rate of 1°C /min to different temperatures of 500°C, 400°C, 300°C and 200?C. When the cooling temperature after sintering inside the furnace is effected at various temperatures from 600°C to 200°C, for a precipitate hardened aluminium compacts with aluminium particle size of 20 μm, the porosity level reduced by 26% and that for aluminium particle size of 150μm, the porosity level reduced by 23%. Marked improvement in micro hardness value is also observed correspondingly.

关键词： Powder Metallurgy Particle Size Cooling Rate Precipitation Hardening Porosity