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Microwave-Assisted Au and Ag Nanoparticle Synthesis: An Energy Phase-Space Projection Analysis
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作者 Victor J. Law Denis P. Dowling 《American Journal of Analytical Chemistry》 CAS 2023年第4期149-174,共26页
Microwave-assisted synthesis of gold and silver nanoparticles, as a function of Green Chemistry, non Green Chemistry, and four applicator types are reported. The applicator types are Domestic microwave ovens, commerci... Microwave-assisted synthesis of gold and silver nanoparticles, as a function of Green Chemistry, non Green Chemistry, and four applicator types are reported. The applicator types are Domestic microwave ovens, commercial temperature controlled microwave chemistry ovens (TCMC), digesters, and axial field helical antennae. For each of these microwave applicators the process energy budget where estimated (Watts multiplied by process time = kJ) and energy density (applied energy divided by suspension volume = kJ·ml<sup>-1</sup>) range between 180 ± 176.8 kJ, and 79.5 ± 79 kJ·ml<sup>-1</sup>, respectively. The axial field helical field an-tenna applicator is found to be the most energy efficient (0.253 kJ·m<sup>-1</sup> per kJ, at 36 W). Followed by microwave ovens (4.47 ± 3.9 kJ·ml<sup>-1</sup> per 76.83 ± 39 kJ), and TCMC ovens (2.86 ± 2.3 kJ·m<sup>-1</sup> per 343 ± 321.5 kJ). The digester applicators have the least energy efficiency (36.2 ± 50.7 kJ·m<sup>-1</sup> per 1010 ± 620 kJ). A comparison with reconstructed ‘non-thermal’ microwave oven inactivation microorganism experiments yields a power-law signature of n = 0.846 (R<sup>2</sup> = 0.7923) four orders of magnitude. The paper provides a discussion on the Au and Ag nanoparticle chemistry and bio-chemistry synthesis aspects of the microwave applicator energy datasets and variation within each dataset. The visual and analytical approach within the energy phase-space projection enables a nanoparticle synthesis route to be systematically characterized, and where changes to the synthesis are to be mapped and compared directly with historical datasets. In order to help identify lower cost nanoparticle synthesis, in addition to potentially reduce synthesis energy to routes informed changes to potentially reduce synthesis energy budget, along with nanoparticle morphology and yield. 展开更多
关键词 Turkevich Microwave-Assisted Synthesis Ag AU HYDROXYAPATITE Nanoparticle FUNCTIONALIZATION Energy Phase-space projection
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NULL-SPACE PROJECTION AND WATERFILLING RESOURCE ALLOCATION IN MULTI-ANTENNA COGNITIVE RADIO NETWORKS
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作者 Rong Mei Zhu Shihua 《Journal of Electronics(China)》 2010年第5期701-707,共7页
Cognitive Radio(CR) is a promising technique for the next generation mobile communi-cation system for its capability to solve the conflicts between the scarcity and underutilization of spectrum.In this paper,aiming at... Cognitive Radio(CR) is a promising technique for the next generation mobile communi-cation system for its capability to solve the conflicts between the scarcity and underutilization of spectrum.In this paper,aiming at maximizing the system capacity of a multi-antenna CR system on the premise that avoid interference to the primary system in the same band simultaneously,a resource allocation method which is able to avoid interference between PRimary(PR) and CR users by pro-jecting the transmit signals of CR users on the null space of the PR users' channels is proposed.CR users with better channel condition are selected,and the interference from CR system to PR users can be removed completely by projecting the transmit signals of CR system on the null-space of PR users' channels.Parallel sub-channels are constructed for CR users through Singular Value Decomposition(SVD).At last,waterfilling is also adopted to increase the CR users' capacity.Simulation result demonstrates that compared with existing methods,our method can improve the achievable sum rate of CR users as well as reduce the outage probability of PR users. 展开更多
关键词 Cognitive Radio (CR) network Resource allocation Null-space projection Waterfilling
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基于Cite Space施工项目成本控制研究述评与展望 被引量:4
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作者 王永莉 徐浪 贾慧慧 《河北建筑工程学院学报》 CAS 2023年第2期168-175,共8页
对施工项目成本控制进行可视化分析和文献计量。分析施工项目成本控制的文献数量态势,并对核心机构、核心作者群、关键词进行Cite Space图谱绘制及文献阅读,得出了施工项目成本控制研究主要呈现三大主题:即理论研究、方法研究、技术研究... 对施工项目成本控制进行可视化分析和文献计量。分析施工项目成本控制的文献数量态势,并对核心机构、核心作者群、关键词进行Cite Space图谱绘制及文献阅读,得出了施工项目成本控制研究主要呈现三大主题:即理论研究、方法研究、技术研究,并对三大主题进行了系统分析和总结。基于此,对施工项目成本控制进行了研究展望。 展开更多
关键词 施工项目 成本控制 Cite space 文献计量
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Some remarks on pseudo-umbilical totally real submanifolds in a complex projective space 被引量:3
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作者 ZHANG Liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期227-232,共6页
This paper studies the relationship between the pseudo-umbilical totally real submanifolds and the minimal totally real submanifolds in a complex projective space. Two theo- rems which claim that some types of pseudo-... This paper studies the relationship between the pseudo-umbilical totally real submanifolds and the minimal totally real submanifolds in a complex projective space. Two theo- rems which claim that some types of pseudo-umbilical totally real submanifolds must be minimal submanifolds are proved. 展开更多
关键词 complex projective space totally real submanifold pseudo-umbilical submanifold minimal submanifold.
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Totally Real Minimal Submanifolds in a Quaternion Projective Space 被引量:4
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作者 舒世昌 贾兴琴 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第1期70-75, ,共6页
Some curvature pinching theorems for compact or complete totally real minimal submanifolds in a quaternion projective space are given,so that the corresponding results due to B. Y.Chen and C. S. Houh as well as Y. B. ... Some curvature pinching theorems for compact or complete totally real minimal submanifolds in a quaternion projective space are given,so that the corresponding results due to B. Y.Chen and C. S. Houh as well as Y. B. Shen are improved and generalized. 展开更多
关键词 quaternion projective space totally real minimal submanifolds curvature pinching
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GEOMETRIC CONSTRUCTION OF ASSOCIATION SCHEMES FROM DEGENERATE QUADRICS INPROJECTIVE SPACES PG(2ν+δ+ι-1, Fq) FOR q ODD 被引量:1
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作者 王恺顺 魏鸿增 《Acta Mathematica Scientia》 SCIE CSCD 2000年第1期35-43,共9页
Let Fq be a finite field with q elements, where q is a power of an odd prime,In this paperl the authors consider a projective space PG(2v + δ + l, Fq) with dimension 2v + δ + l, partitioned into an affine space AG(2... Let Fq be a finite field with q elements, where q is a power of an odd prime,In this paperl the authors consider a projective space PG(2v + δ + l, Fq) with dimension 2v + δ + l, partitioned into an affine space AG(2v + δ + l, Fq) of dimension 2v + δ + l and a hyperplane H = PG(2v + δ + l - 1, Fq) of dimension 2v + δ + l - 1 at infinity, where l ≠0.The points of the hyperplane H are next partitioned into four subsets. A pair of points a and b of the affine space is defined to belong to class i if the line ab meets the subsct i of H. Finally, a family of four-class association schemes are constructed, and parameters are also computed. 展开更多
关键词 projective space QUADRIC association scheme
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2-Harmonic Totally Real Submanifolds in a Complex Projective Space
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作者 孙弘安 《Chinese Quarterly Journal of Mathematics》 CSCD 1995年第3期37-41,共5页
In this paper, we discuss the relations between the 2-harmornic totally real submsnifold and the minimal totall real submanifold in the complex protective spsace, and obtain the pinching conductions for the second fu... In this paper, we discuss the relations between the 2-harmornic totally real submsnifold and the minimal totall real submanifold in the complex protective spsace, and obtain the pinching conductions for the second fundamental form and the Rieci curature of the 2-harmornic totally real submanifold in the complex projective space. 展开更多
关键词 complex projective space totally real 2-HARMONIC MINIMAL
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A Note on Totally Real Riemannian Foliations with Parallelized Mean Curvature Vectors in a Complex Projective Space
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作者 PENG Hui-chun 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第3期410-414,共5页
We discussed a totally real Riemannian foliations with parallel mean curvature on a complex projective space.We carried out the divergence of a vector field on it and obtained a formula of Simons’type.
关键词 Riemannian foliations complex projective space mean curvature DIVERGENCE
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A Characterization of Complex Projective Spaces by Sections of Line Bundles
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作者 Shuyu Liang Yanan Gao Yicai Zhao 《Advances in Pure Mathematics》 2015年第8期450-453,共4页
Let M be a n-dimensional compact irreducible complex space with a line bundle L. It is shown that if M is completely intersected with respect to L and dimH0(M, L) = n + 1, then M is biholomorphic to a complex projecti... Let M be a n-dimensional compact irreducible complex space with a line bundle L. It is shown that if M is completely intersected with respect to L and dimH0(M, L) = n + 1, then M is biholomorphic to a complex projective space Pn of dimension n. 展开更多
关键词 Complex space projectIVE space LINE BUNDLE COMPLETE Intersected
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Korean Participation in the Galex Ultraviolet Space Telescope Project
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作者 Young Wook Lee (Center for Space Astrophysics, Yonsei University, Seoul 120-749, Korea) 《天文研究与技术》 CSCD 1999年第S1期8-10,共3页
The Center for Space Astrophysics at Yonsei university, Seoul, Korea, is actively participating in the development and operation of the Galaxy Evolution Explorer (GALEX), a NASA ultraviolet space telescope project to ... The Center for Space Astrophysics at Yonsei university, Seoul, Korea, is actively participating in the development and operation of the Galaxy Evolution Explorer (GALEX), a NASA ultraviolet space telescope project to be launched in late 2001. As the first official case of NASA Korea cooperation on major space science program, this project will greatly expand the capability of Korean astronomy into space based operations. 展开更多
关键词 Korean Participation in the Galex Ultraviolet space Telescope project
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THE CONTRACTION LINEAR METRIC PROJECTIONS IN L_p SPACES
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作者 Song Wenhua (Hebei University of Economics, China) 《Approximation Theory and Its Applications》 2002年第4期20-30,共11页
In this paper, we study the contraction linearity for metric projection in L p spaces. A geometrical property of a subspace Y of L p is given on which P Y is a contraction projection.
关键词 THE CONTRACTION LINEAR METRIC projectIONS IN L_p spaceS
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Project Systems Engineering for Developing Space Robots
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作者 Li Gengtian, Li ZhibinBeijing Institute of Control Engineering, P.O.Box 2729, Beijing 100080, ChinaLü YingxiangBeijing Institute of Electromechanic System Engineering.P.O.Box 142-206, Beijing 100854, China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1991年第1期97-106,共10页
Space robots possess unique distinguishing features unlike general robots on earth, due to the particular environments in space. The developing of various practical space robots promoting the improvement of space scie... Space robots possess unique distinguishing features unlike general robots on earth, due to the particular environments in space. The developing of various practical space robots promoting the improvement of space science and technology is a complex man-machine-environment engineering problem. This paper analyses from the systems engineering viewpoint the space robot system in the scope of the architecture of robotics discipline, space environment characteristics, man-machine-environment system of space robots, the general methodology of project systems engineering and the process of space robot systems engineering. 展开更多
关键词 space robots Systems engineering project systems engineering.
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China Space Benefit Project
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《Aerospace China》 1998年第2期3-4,共2页
ChinaSpaceBenefitProjectisalargesystemengineeringpro-jectproposedbyChinaAerospaceCorporation(CASC)forconsid-... ChinaSpaceBenefitProjectisalargesystemengineeringpro-jectproposedbyChinaAerospaceCorporation(CASC)forconsid-erationbytheChine... 展开更多
关键词 China space Benefit project
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A Relation between Resolvents of Subdifferentials and Metric Projections to Level Sets
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作者 Hiroko Okochi 《Applied Mathematics》 2023年第6期428-435,共8页
An equation concerning with the subdifferential of convex functionals defined in real Banach spaces and the metric projections to level sets is shown. The equation is compared with the resolvents of general monotone o... An equation concerning with the subdifferential of convex functionals defined in real Banach spaces and the metric projections to level sets is shown. The equation is compared with the resolvents of general monotone operators, and makes the geometric properties of differential equations expressed by subdifferentials clear. Hence, it can be expected to be useful in obtaining the steepest descents defined by the convex functionals in Banach spaces. Also, it gives a similar result to the Lagrange multiplier method under certain conditions. 展开更多
关键词 SUBDIFFERENTIAL Convex Functional Monotone Operator RESOLVENT Lagrange Multiplier Banach space Metric projection
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考虑电力网络约束的工业园区虚拟电厂调控边界求解方法
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作者 廖思阳 贺聪 +3 位作者 李玲芳 徐箭 孙元章 柯德平 《电力系统自动化》 EI CSCD 北大核心 2024年第18期66-75,共10页
构建以新能源为主体的新型电力系统,亟须挖掘负荷侧灵活调节资源参与电网调控。含电解铝、矿热炉等高耗能负荷的工业园区具备良好的调控潜力,但是考虑园区内部电力网络约束,其精确调控边界求解面临着变量维数高、约束非线性的难题,现有... 构建以新能源为主体的新型电力系统,亟须挖掘负荷侧灵活调节资源参与电网调控。含电解铝、矿热炉等高耗能负荷的工业园区具备良好的调控潜力,但是考虑园区内部电力网络约束,其精确调控边界求解面临着变量维数高、约束非线性的难题,现有方法不能较好地兼顾计算效率和精度。对此,文中将上述问题抽象为高维非线性状态空间在P-Q耦合平面的投影问题:分别建立考虑工业园区安全运行线性化和非线性约束的调控边界投影求解模型,采用一种新颖的高维状态空间投影算法,通过顶点“搜索-映射”的两步式求解过程,得到工业园区型虚拟电厂调控边界的精确投影。算例结果表明,采用所提方法求解的调控边界可由线性不等式组完全表征,与现有调度系统完全兼容,结合与叠加柔性资源调控能力和传统采样方法的对比,验证了该方法的可行性以及高求解精度和效率。 展开更多
关键词 工业园区 虚拟电厂 调控边界 电力网络约束 高维状态空间投影
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Project New Orion: Pulsed Nuclear Space Propulsion Using Photofission Activated by Ultra-Intense Laser 被引量:2
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作者 Robert LeMoyne Timothy Mastroianni 《Journal of Applied Mathematics and Physics》 2016年第4期630-636,共7页
Project New Orion entails a pulsed nuclear space propulsion system that utilizes photofission through the implementation of an ultra-intense laser. The historical origins derive from the endeavors of Project Orion, wh... Project New Orion entails a pulsed nuclear space propulsion system that utilizes photofission through the implementation of an ultra-intense laser. The historical origins derive from the endeavors of Project Orion, which utilized thermonuclear devices to impart a considerable velocity increment on the respective spacecraft. The shear magnitude of Project Orion significantly detracts from the likelihood of progressive research development testing and evaluation. Project New Orion incorporates a more feasible pathway for the progressive research development testing and evaluation of the pulsed nuclear space propulsion system. Photofission through the application of an ultra-intense laser enables a much more controllable and scalable nuclear yield. The energy source for the ultra-intense laser is derived from a first stage liquid hydrogen and liquid oxygen chemical propulsion system. A portion of the thermal/kinetic energy of the rocket propulsive fluid is converted to electrical energy through a magneto-hydrodynamic generator with cryogenic propellant densification for facilitating the integral superconducting magnets. Fundamental analysis of Project New Orion demonstrates the capacity to impart a meaningful velocity increment through ultra-intense laser derived photofission on a small spacecraft. 展开更多
关键词 project Orion Pulsed Nuclear space Propulsion PHOTOFISSION Nuclear Fission Ultra-Intense Laser Magneto-Hydrodynamic Generator Cryogenic Propellant Densification
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CONVERGENCE ANALYSIS OF A MONOTONE PROJECTION ALGORITHM IN REFLEXIVE BANACH SPACES
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作者 秦小龙 Sun Young CHO 《Acta Mathematica Scientia》 SCIE CSCD 2017年第2期488-502,共15页
In this article, fixed points of generalized asymptotically quasi-Ф-nonexpansive mappings and equilibrium problems are investigated based on a monotone projection algo- rithm. Strong convergence theorems are establis... In this article, fixed points of generalized asymptotically quasi-Ф-nonexpansive mappings and equilibrium problems are investigated based on a monotone projection algo- rithm. Strong convergence theorems are established without the aid of compactness in the framework of reflexive Banach spaces. 展开更多
关键词 Asymptotically quasi-Ф-nonexpansive mapping Banach space equilibrium problem fixed point Generalized projection
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制氢厂房氢泄漏激光检测光路布置优化研究
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作者 李栋 李雪松 +3 位作者 王迪 吕妍 濮御 李玉爽 《化工自动化及仪表》 CAS 2024年第4期599-606,718,共9页
氢气扩散能力强、燃烧速度快、可燃范围广的特点使其泄漏易发生爆炸事故。对比基于可调谐半导体激光吸收光谱技术的激光传感器布置方式,以降低对氢泄漏的检测时间,获得最佳光路布置间距和角度。利用数值模拟研究了氢气在制氢厂房内的泄... 氢气扩散能力强、燃烧速度快、可燃范围广的特点使其泄漏易发生爆炸事故。对比基于可调谐半导体激光吸收光谱技术的激光传感器布置方式,以降低对氢泄漏的检测时间,获得最佳光路布置间距和角度。利用数值模拟研究了氢气在制氢厂房内的泄漏逸散规律,通过光学仿真确定了激光传感器的最短布置距离,分析了相邻光路间距及光路投影角度两种因素对氢泄漏检测的影响,得到了检测时间短、经济成本相对较低的布置方式。结果表明:相邻光路间距为0.4 m、光路与地面夹角为45°时,检测氢气泄漏时间优于其他方式并且所需激光传感器数量最少。 展开更多
关键词 激光检测 制氢厂房 氢气泄漏 光路布置 光路间距 光路投影角度
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南极长城站哨声波监测仪设备及其初步观测
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作者 顾旭东 倪彬彬 +6 位作者 徐未 王市委 李斌 胡泽骏 何昉 陈相材 胡红桥 《地球与行星物理论评(中英文)》 2024年第1期15-23,共9页
在子午工程二期项目的支持下,武汉大学(Wuhan University,WHU)联合中国极地研究中心研制了一套甚低频(very low frequency,VLF)波动探测系统,并在2022年由中国极地研究中心部署于南极洲的中国长城站(Great Wall Station,GWS,62.22°... 在子午工程二期项目的支持下,武汉大学(Wuhan University,WHU)联合中国极地研究中心研制了一套甚低频(very low frequency,VLF)波动探测系统,并在2022年由中国极地研究中心部署于南极洲的中国长城站(Great Wall Station,GWS,62.22°S,58.96°W).该探测系统的动态范围为~110 dB,时间精度为~100 ns,可为空间物理和空间天气研究提供高分辨率的波动观测数据.本文详细介绍了WHU VLF(子午工程编码:OCHCH_WHWM01)波动探测系统在GWS的初步观测结果,充分验证了系统的优越性能和稳定性.在过去一年的常规运行中,此系统能精确探测北美和欧洲等区域内各种地基VLF台站信号的动态变化.初步分析结果表明,在多次X级太阳耀斑爆发期间,GWS观测到的人工VLF台站信号特性与以往的研究结果高度一致.由于HWU-GWS(HWU为发射台站的名称)路径穿过南大西洋异常(south Atlantic anomaly,SAA)区域,观测结果同时表明,在磁暴期间,HWU VLF信号的扰动与磁层电子沉降在时空关系上具有很强的关联性.此外,此设备也能观测到闪电激发的宽频带哨声波,在频谱图上呈现特有的清晰色散结构.因此,在南极独特的地理位置,地基哨声波监测仪的观测结合其它仪器的观测,有利于深入开展与极区哨声波传播、低电离层扰动、地面闪电放电和辐射带粒子沉降等相关的空间天气学研究,对开展全天时空间环境监测具有重要意义. 展开更多
关键词 哨声波监测仪 南极长城站 空间天气 甚低频波动传播 子午工程
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NASA重大项目预研管理过程研究——以韦布望远镜为例
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作者 郭世杰 李泽霞 +1 位作者 魏韧 董璐 《世界科技研究与发展》 CSCD 2024年第5期628-641,共14页
做好重大科技项目的组织管理是实现抢占科技制高点目标的重要前提条件。本文以美国国家航空航天局(National Aeronautics and Space Administration,NASA)系列管理文件为分析对象,剖析其项目组织管理模式,并以投资近百亿美元、持续数十... 做好重大科技项目的组织管理是实现抢占科技制高点目标的重要前提条件。本文以美国国家航空航天局(National Aeronautics and Space Administration,NASA)系列管理文件为分析对象,剖析其项目组织管理模式,并以投资近百亿美元、持续数十年的詹姆斯·韦布太空望远镜项目为例,对NASA重大项目预研管理过程进行分析。NASA将项目按照成本、风险、是否属于优先事项等分为3个类别进行管理,项目生命周期可以分为从“A前”(pre-A)到A、B直至F共7个阶段。韦布望远镜从1995年进入NASA的“A前阶段”,由3家单位独立开展概念研究;1999年7月从3家单位中遴选2家开始“A阶段”研究;2002年9月正式选择1家单位牵头开展“B阶段”研究。可供我国借鉴之处包括:项目组织方应发挥好“总体”角色,凝聚多方资源、提供长期稳定支持;新项目的酝酿需充分利用前期项目的科学、技术、管理人才基础;可利用“赛马制”等分阶段推进重大项目的实施,以降低不确定性和决策风险等。 展开更多
关键词 重大项目 NASA 预研管理 詹姆斯·韦布太空望远镜 组织管理模式
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