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采用非稳相偏振滤波的DAS-VSP数据P/S波分离方法及其应用
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作者 王腾飞 程玖兵 +3 位作者 孟涛 曹中林 胡善政 段鹏飞 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2024年第7期2761-2772,共12页
分布式光纤声学传感(DAS)因成本低、易布设以及高密度采样等优势正成为重要的地震观测技术,尤其是越来越多地与垂直地震剖面(VSP)结合,用于主动地震勘探或被动地震监测.DAS传感器通过感知弹性波场产生的轴向应变或应变速率来观测地震波... 分布式光纤声学传感(DAS)因成本低、易布设以及高密度采样等优势正成为重要的地震观测技术,尤其是越来越多地与垂直地震剖面(VSP)结合,用于主动地震勘探或被动地震监测.DAS传感器通过感知弹性波场产生的轴向应变或应变速率来观测地震波场振动.然而,目前单分量DAS-VSP数据未完整地记录地下弹性波场的三维矢量振动信号,因此如何从中分离出P波或S波用于后续地震成像与参数反演是重要且很有挑战的课题.以弹性波传播理论为基础,本文根据P波和S波的频散关系估算接收点处各自的偏振方向,通过随频率和空间位置变化的偏振滤波实现DAS-VSP数据的P/S波分离.理论模型合成数据与东海实际DAS-VSP数据实验结果表明,该方法能有效地将P波和S波信号从单分量DAS-VSP数据中分离出来,可为后续纵横波速度反演、PP与PS波成像提供关键的数据预条件处理. 展开更多
关键词 分布式光纤声学传感(DAs) VsP P/s波分离 偏振投影 非稳相滤波
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基于BIM+B/S的水库工程数字化展示平台的构建
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作者 杨玲 李靖 +1 位作者 王飞 樊兴东 《水利信息化》 2024年第2期69-73,共5页
针对水库工程在初步设计阶段仍以二维图纸作为成果交付,缺少对工程整体情况、投资估算等关键信息直观展示的问题,将BIM数字信息建模、BIM数据文件优化处理、B/S前后端分离、跨平台访问等技术应用于新建岔河水库工程,建立岔河水库枢纽BI... 针对水库工程在初步设计阶段仍以二维图纸作为成果交付,缺少对工程整体情况、投资估算等关键信息直观展示的问题,将BIM数字信息建模、BIM数据文件优化处理、B/S前后端分离、跨平台访问等技术应用于新建岔河水库工程,建立岔河水库枢纽BIM模型,创建实现平台功能的数据文件并构建岔河水库枢纽工程数字化展示平台。研究结果表明:构建的岔河水库工程数字化展示平台可以高效、流畅、跨平台地在电脑端和手机端,向参建各方展示待建枢纽工程的基本情况和地理位置,建筑物三维信息模型,单体工程的施工模拟动画,以及枢纽工程投资估算关键信息。研究结果深化BIM技术应用程度,可为其他水利工程信息化提供重要参考和借鉴价值。 展开更多
关键词 BIM B/s 数字化展示平台 水库工程
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Review of the Relocation of General Zhang Fei’s Temple in View of the Three Gorges Dam Project
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作者 Yuhua Zhu Fuhan Liu 《Journal of World Architecture》 2023年第6期19-29,共11页
As a national cultural property,General Zhang Fei’s Temple is the largest ancient architectural complex in the Three Gorges of the Yangtze River.It was built in the Han Dynasty and has a long history of nearly 2,000 ... As a national cultural property,General Zhang Fei’s Temple is the largest ancient architectural complex in the Three Gorges of the Yangtze River.It was built in the Han Dynasty and has a long history of nearly 2,000 years.In 1994,the Chinese government launched the Three Gorges Dam project at the Yangtze River and implemented the largest relocation project for the General Zhang Fei Temple to prevent it from being submerged.The temple was relocated 32 kilometers upstream along with the local people of Yunyang County,and the historic environment was rebuilt on the opposite side of the migrant city of New Yunyang County.The temple was restored successfully and the tradition of offering sacrifices to General Zhang Fei continued in the local community.The relocation project lasted for 8 years and became the largest cultural heritage conservation project of the People’s Republic of China at the end of the 20th century.This paper comprehensively summarizes and reviews the project goals,implementation process,and project highlights of this relocation,so as to provide an important case reference for heritage conservation projects in the future. 展开更多
关键词 General Zhang Fei’s Temple Relocation project Three Gorges Dam project Heritage conservation
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Analysis of debris flow control effect and hazard assessment in Xinqiao Gully,Wenchuan M_(s)8.0 earthquake area based on numerical simulation
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作者 Chang Yang Yong-bo Tie +3 位作者 Xian-zheng Zhang Yan-feng Zhang Zhi-jie Ning Zong-liang Li 《China Geology》 CAS CSCD 2024年第2期248-263,共16页
Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the eff... Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events. 展开更多
关键词 Landslide Debris flow Hazard assessment Numerical simulation OpenLIsEM Prevention and control project Wenchuan M_(s)8.0 earthquake Xinqiao Gully sichuan province Geological hazards survey engineering
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基于B/S架构的建筑工程项目智慧工地信息管理平台设计 被引量:1
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作者 陈弘宇 徐缤荣 +1 位作者 张吉红 常朝朝 《无线互联科技》 2024年第12期53-55,共3页
常规建筑工程项目智慧工地信息管理平台多采用云计算技术,信息管理效率偏低。为此,文章提出了基于B/S架构的建筑工程项目智慧工地信息管理平台设计;选取温湿度传感器与热成像传感器作为平台的信息采集模块的应用硬件;引入B/S架构建立平... 常规建筑工程项目智慧工地信息管理平台多采用云计算技术,信息管理效率偏低。为此,文章提出了基于B/S架构的建筑工程项目智慧工地信息管理平台设计;选取温湿度传感器与热成像传感器作为平台的信息采集模块的应用硬件;引入B/S架构建立平台的数据库,并通过添加数据索引表提升信息的查询速率,实现平台的信息管理功能。测试结果表明,所设计的平台能够提高施工信息的管理效率,管理效果较好。 展开更多
关键词 B/s架构 建筑工程项目 工地信息管理平台 管理效率
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Momentum as Translations at Conformal Infinity
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作者 Richard James Petti Jacob Luke Graham 《Journal of Applied Mathematics and Physics》 2024年第4期1522-1540,共19页
Although General Relativity is the classic example of a physical theory based on differential geometry, the momentum tensor is the only part of the field equation that is not derived from or interpreted with different... Although General Relativity is the classic example of a physical theory based on differential geometry, the momentum tensor is the only part of the field equation that is not derived from or interpreted with differential geometry. This work extends General Relativity and Einstein-Cartan theory by augmenting the Poincaré group with projective (special) conformal transformations, which are translations at conformal infinity. Momentum becomes a part of the differential geometry of spacetime. The Lie algebra of these transformations is represented by vectorfields on an associated Minkowski fiber space. Variation of projective conformal scalar curvature generates a 2-index tensor that serves as linear momentum in the field equations of General Relativity. The computation yields a constructive realization of Mach’s principle: local inertia is determined by local motion relative to mass at conformal infinity in each fiber. The vectorfields have a cellular structure that is similar to that of turbulent fluids. 展开更多
关键词 projective symmetry Conformal symmetry MOMENTUM General Relativity Einstein-Cartan Mach’s Principle
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B/S架构在工程结算管理信息系统中的应用
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作者 谭金娥 《移动信息》 2024年第7期398-400,共3页
随着信息技术的飞速发展,B/S架构因其轻量化的客户端、高效的资源共享与全球连通性以及对于现代Web技术栈的充分利用,已成为现代信息系统开发的重要范式。文中概述了B/S架构的定义与特征,详细介绍了该架构在工程结算管理信息系统中的技... 随着信息技术的飞速发展,B/S架构因其轻量化的客户端、高效的资源共享与全球连通性以及对于现代Web技术栈的充分利用,已成为现代信息系统开发的重要范式。文中概述了B/S架构的定义与特征,详细介绍了该架构在工程结算管理信息系统中的技术组成、系统设计、功能模块划分及技术选型策略,最后通过用户交互设计、数据处理与分析、系统安全与维护等方面的举措,展示了B/S架构如何在实际应用中发挥其先进性和灵活性。 展开更多
关键词 B/s架构 工程结算 信息系统
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基于改进D-S的高速公路改扩建交通安全风险评估模型
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作者 高明生 吴忠广 +2 位作者 张振虎 田万利 朱强 《交通运输研究》 2023年第1期105-114,共10页
为提高高速公路改扩建工程交通安全风险评估结果的确定性和准确性,建立了基于改进D-S证据理论的相关风险评估模型。首先建立包含24个影响因素的三层级评估指标体系;然后利用云模型(Cloud Model,CM)求出定性指标的基本信度赋值(Basic Pro... 为提高高速公路改扩建工程交通安全风险评估结果的确定性和准确性,建立了基于改进D-S证据理论的相关风险评估模型。首先建立包含24个影响因素的三层级评估指标体系;然后利用云模型(Cloud Model,CM)求出定性指标的基本信度赋值(Basic Probability Assignment,BPA),利用高斯隶属度函数求出定量指标BPA;接着,通过层次分析法确定各评估指标的权重,进而对各指标BPA进行加权;利用D-S证据理论融合加权后的BPA,归一化处理后得到改扩建工程交通安全风险状态评估结果。最后,为验证模型的准确性,选取沪陕高速公路平潮至广陵段高速公路改扩建工程作为实例进行交通安全风险评估。评估结果显示,实例工程的低风险水平隶属度最大,为0.6615,表明该实例总体处于低风险水平,与现有资料和现实情况吻合。同时发现,基于CM、AHP及D-S证据理论的评估模型对各评估指标进行量化、加权、融合后所得到的风险等级隶属度和不确定性有所区别,能更均衡地表示风险的隶属度,量化后的安全风险状态评估结果具有更好的准确性,解决了指标体系中模糊定性指标难以量化表征及指标差异化权重赋值的难题。 展开更多
关键词 交通安全 改扩建工程 风险评估 层次分析 云模型 D-s证据理论
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Inequalities relating to L_p-version of Petty's conjectured projection inequality 被引量:1
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作者 王卫东 冷岗松 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第2期269-276,共8页
Petty's conjectured projection inequality is a famous open problem in the theory of convex bodies. In this paper, it is shown that an inequality relating to Lp-version of the Petty's conjectured projection inequalit... Petty's conjectured projection inequality is a famous open problem in the theory of convex bodies. In this paper, it is shown that an inequality relating to Lp-version of the Petty's conjectured projection inequality is developed by using the notions of the Lp-mixed volume and the Lp-dual mixed volume, the relation of the Lp-projection body and the geometric body Г-pK, the Bourgain-Milman inequality and the Lp-Bnsemann-Petty inequality. In addition, for each origin-symmetric convex body, by applying the Jensen inequality and the monotonicity of the geometric body Г-pK, the reverses of Lp-version of the Petty's conjectured projection inequality and the Lp-Petty projection inequality are given, respectively. 展开更多
关键词 Lp-version Petty projection inequality Petty's conjectured projectioninequality Lp-projection body REVERsE
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Three-dimensional stereotactic surface projection in the statistical analysis of single photon emission computed tomography data for distinguishing between Alzheimer's disease and depression 被引量:1
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作者 Eiji Kirino 《World Journal of Psychiatry》 SCIE 2017年第2期121-127,共7页
AIM To evaluate usefulness of single photon emission computed tomography(SPECT) with three-dimensional stereotactic surface projection(3D-SSP) in distinguishing between Alzheimer's disease(AD) and depression.METHO... AIM To evaluate usefulness of single photon emission computed tomography(SPECT) with three-dimensional stereotactic surface projection(3D-SSP) in distinguishing between Alzheimer's disease(AD) and depression.METHODS We studied 43 patients who presented with both depressive symptoms and memory disturbance. Each subject was evaluated using the following:(1) the Minimal Mental State Examination;(2) the Hamilton Rating Scale for Depression;(3) Clinical Global Impression-Severity scale(CGI-S); and(4) SPECT imaging with 3D-SSP.RESULTS The MMSE scores correlated significantly with the maximum Z-scores of AD-associated regions. CGI-S scores correlated significantly with the maximum Z-scores of depression-associated regions. Factor analysis identified three significant factors. Of these, Factor 1 could be interpreted as favouring a tendency for AD, Factor 2 as favouring a tendency for pseudo-dementia, and Factor 3 as favouring a depressive tendency.CONCLUSION We investigated whether these patients could be categorized as types: Type A(true AD), Type B(pseudodementia), Type C(occult AD), and Type D(true depression). The factor scores in factor analysis supported the validity of this classification. Our results suggest that SPECT with 3D-SSP is highly useful for distinguishing between depression and depressed mood in the early stage of AD. 展开更多
关键词 Alzheimer’s disease THREE-DIMENsIONAL sTEREOTACTIC surface projection single photon emission COMPUTED tomography Pseudo-dementia DEPREssION
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PROJECTIVELY FLAT FINSLER METRICS WITH ALMOST ISOTROPIC S-CURVATURE 被引量:3
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作者 程新跃 沈忠民 《Acta Mathematica Scientia》 SCIE CSCD 2006年第2期307-313,共7页
This article characterizes projectively fiat Finsler metrics with almost isotropic S-curvature.
关键词 projectively flat Finsler metric s-CURVATURE the flag curvature Randers metric
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Current Situations of Competitive Scientific Research Projects for Agri-scientific Research Institutions: A Case Study of Tropical Crops Genetic Resources Institute of Chinese Academy of Tropical Agricultural Sciences
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作者 Haiyan LUO Qingqun YAO +1 位作者 Lizhen CHEN Yu ZHENG 《Asian Agricultural Research》 2015年第10期77-82,共6页
This paper collected and arranged competitive scientific research projects undertaken by Tropical Crops Genetic Resources Institute of Chinese Academy of Tropical Agricultural Sciences in 2003-2014. Through statistica... This paper collected and arranged competitive scientific research projects undertaken by Tropical Crops Genetic Resources Institute of Chinese Academy of Tropical Agricultural Sciences in 2003-2014. Through statistical analysis on quantity of projects,funded amount,age of person responsible,professional title of person responsible,academic degree of person responsible,research object,it discussed relevant characteristics and rules. Finally,it came up with pertinent measures and recommendations,in the hope of providing services for decision-making and scientific and technological management. 展开更多
关键词 COMPETITIVE sCIENTIFIC research projects CURRENT s
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A Comparative Overview of Three Gorges Project's Sediment Handling
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作者 CHEN Ji-shengProfessor-senior Engineer, PhD, Director Emeritus, Yangtze River Scientific Research Institute, Wuhan 430010, Hubei 《人民长江》 北大核心 2002年第S1期22-27,共6页
Water projects’ sediment deposition problems always cause widespread concerns. The gravity of them varies in accordance not only with reservoirs’ natural and socio-economic characteristics but also with their modes ... Water projects’ sediment deposition problems always cause widespread concerns. The gravity of them varies in accordance not only with reservoirs’ natural and socio-economic characteristics but also with their modes of operation. The unique characteristics, configuration and mode of operation of Three Gorges Project (TGP) reservoir are compared with those of several existing large reservoirs in this paper. As many reservoirs are troubling environment by gradually extending coarse sediment deposition at the uppermost end of fluctuating backwater region toward upstream, Gezhouba reservoir on Yangtze and Danjiangkou reservoir on Hanjiang have shown no trace of such upstream extension of sediment deposition in relevant prototype observation data for the past 20 and more years. TGP reservoir’s in-coming flow sediment conditions and configuration in plane are almost the same as those of Gezhouba reservoir, and TGP reservoir’s mode of operation(usually keeping a very low pool level for flood control in flood season and storing up in-coming flow only thenceafter) is similar to that of Danjiangkou reservoir. New findings of sediment research and prototype flow sediment investigations as well as new agenda of large hydro projects’ construction on Jinshajiang in nearest future assure the prospects of TGP sediment handling. 展开更多
关键词 Three Gorges project sEDIMENT HANDLING reservoir’s CONFIGURATION reservoir’s mode of operation
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Controllable precision of the projective truncation approximation for Green's functions
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作者 Peng Fan Ning-Hua Tong 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第4期317-325,共9页
Recently, we developed the projective truncation approximation for the equation of motion of two-time Green's functions(Fan et al., Phys. Rev. B 97, 165140(2018)). In that approximation, the precision of results d... Recently, we developed the projective truncation approximation for the equation of motion of two-time Green's functions(Fan et al., Phys. Rev. B 97, 165140(2018)). In that approximation, the precision of results depends on the selection of operator basis. Here, for three successively larger operator bases, we calculate the local static averages and the impurity density of states of the single-band Anderson impurity model. The results converge systematically towards those of numerical renormalization group as the basis size is enlarged. We also propose a quantitative gauge of the truncation error within this method and demonstrate its usefulness using the Hubbard-I basis. We thus confirm that the projective truncation approximation is a method of controllable precision for quantum many-body systems. 展开更多
关键词 projectIVE TRUNCATION APPROXIMATION two-time Green’s functions sINGLE-BAND ANDERsON impurity model numerical RENORMALIZATION group
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Present Situation and Projection of Tibet's Population
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《China Population Today》 1997年第Z1期28-28,共1页
The following is up-to-date inform at ion about Tibet's Population.In 1995,there was a population about 2.43 million in the region,according to my estima-tion based on data from the 1990 census and annual sam-plin... The following is up-to-date inform at ion about Tibet's Population.In 1995,there was a population about 2.43 million in the region,according to my estima-tion based on data from the 1990 census and annual sam-pling surveys.The birth rate was 28 per thousand,the death rate ten per thousand and the natural increase rate 18 per thousand. 展开更多
关键词 Tibet’s and projectION sITUATION POPULATION PREsENT
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ZTE Bags China Telecom's Largest Metropolitan NGN Project
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《ZTE Communications》 2006年第1期47-47,共1页
关键词 ZTE Bags China Telecom’s Largest Metropolitan NGN project project NGN
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Von Neumann’s Theory, Projective Measurement, and Quantum Computation
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作者 Koji Nagata Tadao Nakamura 《Journal of Applied Mathematics and Physics》 2015年第7期874-897,共24页
We discuss the fact that there is a crucial contradiction within Von Neumann’s theory. We derive a proposition concerning a quantum expected value under an assumption of the existence of the orientation of reference ... We discuss the fact that there is a crucial contradiction within Von Neumann’s theory. We derive a proposition concerning a quantum expected value under an assumption of the existence of the orientation of reference frames in N spin-1/2 systems (1 ≤ N to a new constant . It may be said that a new type of the quantum theory early approaches Newton’s theory in the macroscopic scale than the old quantum theory does. We discuss how our solution is used in an implementation of Deutsch’s algorithm. 展开更多
关键词 Von Neumann’s THEORY projectIVE MEAsUREMENT and QUANTUM COMPUTATION
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Project Manager's Competencies in Czech Lottery Industry Enterprise
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作者 Katerina Hrazdilova Bockova Monika Dohnanska +1 位作者 Daniela Hilciikova Radka Vanickova 《Economics World》 2016年第6期274-282,共9页
The presented paper analyses competencies of project manager of the enterprises operating on Czech lottery market. The contribution of the paper consists of two parts. The first part focuses on the basic terminology i... The presented paper analyses competencies of project manager of the enterprises operating on Czech lottery market. The contribution of the paper consists of two parts. The first part focuses on the basic terminology issues and anchors concepts such as project manager and competencies. The second part is dedicated to the analyzing and evaluation of the competencies of ideal project manager of the enterprises operating on Czech lottery market and subsequent presentation and verification. For the analyzing and evaluation of the competencies of ideal project manager, the questionnaire of the scale type with the grade valuation 1-6 was applied within the frame of 20 enterprises operating on the lottery market in Czech Republic. The respondents were from the AG CZ, Ltd. and the competitors of this enterprise. Analyzed data were after the evaluation worked up into the form of graphs. The final output of this paper is the definition of the competencies of ideal project manager operating on Czech lottery market. The paper arose thanks to the project supportted by The Ministry of Education, Slovakia (Project KEGA No. 001DTI-4/2015, proposal of behavior strategies in the difficult social situations in the management of secondary school using the innovative predictive software tools) in cooperation of Dubnicky, Technological lnstitut in Dubnica nad Vahom with AG CZ, Ltd. and The Institute of Technological and Business in Ceske Budejovice. 展开更多
关键词 Czech lottery market lottery enterprise competencies of project managers Czech Republic competency model of project managers definition of project manager's competencies
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The Project “Study on Technology for Manufacture of High-Spheroidicity FCC Catalysts” Passed SINOPEC's Appraisal
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《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第1期23-23,共1页
On January 7, 2015 the project "Study on the technology formanufacture of high-spheroidicity FCC catalysts "undertakenby the SINOPEC Research Institute of Petroleum Processing(RIPP) has passed the technical apprai... On January 7, 2015 the project "Study on the technology formanufacture of high-spheroidicity FCC catalysts "undertakenby the SINOPEC Research Institute of Petroleum Processing(RIPP) has passed the technical appraisal organized by theScience and Technology Division of the Sinopec Corp. 展开更多
关键词 FCC The project Passed sINOPEC’s Appraisal study on Technology for Manufacture of High-spheroidicity FCC Catalysts
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LIRR's Project of “Study on Spalling Mechanism Mechanism of Dense Refractory Castables by Rapid Heating-up” Being Obtained the Support from National Natural Natural Science Foundation of China
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《China's Refractories》 CAS 2011年第3期21-21,共1页
LIRR's Priject of "Research on Spalling Mechanism Due to Rapid Heating-up of Dense Refractory Castables" declared by Wang Zhanmin,vice-president of LIRR,will gain the fund support from National Natural Science Foun... LIRR's Priject of "Research on Spalling Mechanism Due to Rapid Heating-up of Dense Refractory Castables" declared by Wang Zhanmin,vice-president of LIRR,will gain the fund support from National Natural Science Foundation of China in 2011. 展开更多
关键词 LIRR’s project of study on spalling Mechanism Mechanism of Dense Refractory Castables by Rapid Heating-up Being Obtained the support from National Natural Natural science Foundation of China project
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