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DX桩 4

模型试验 4

快速充电 2

承载力 2

策略 2

1860 MPa等级 1

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Cascaded 型检测器 1

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FLTD型脉冲加速器 1

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ISO 9705 1

ISO标准火灾实验系统 1

LED灯具；加速老化测试；中位寿命；滑动平均误差 1

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The Fast Road of Shale Gas Development in China —Reflections on Building a Special Test Areas for National

Da-wei Zhang

《工程管理前沿（英文）》 2015年第2卷第4期页码 364-372 doi: 10.15302/J-FEM-2015062

摘要： China’s shale gas development has had a good start. It is necessary that the developers take advantage of the opportunity to make further efforts to promote shale gas development in China, in particular by rolling out a comprehensive plan on a national level. The author makes a proposal to establish a special shale gas test area in and adjacent to the Sichuan Basin as the most important way to promote the rapid development of shale gas in China. For this purpose, the author analyzes the current situation and problems of shale gas development in China, addresses the necessity and feasibility of establishing a special test area for shale gas development, and draws up the scope of this shale gas special test area of about 450 thousand square kilometers, covering Sichuan, Chongqing, Guizhou, and part of Yunnan, Hunan, Hubei provinces, and proposes the establishment of a shale gas test area in China. This consists of an overall plan, targets, and contents in 10 aspects, along with organization and implementation modes. The shale gas exploration and development in the shale gas zones is promoted vigorously by introducing special policies and innovating exploration, development and utilization model. While at the same time, the shale gas zones of continental facies in the Ordos Basin and marine-terrigenous facies in South Hubei Basin will be established. The experiences of the reform in the shale gas zones will be the good practice for the reform of petroleum organization system.

关键词： China shale gas exploration and development reform special shale gas test area (shale gas zone)

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Heat transfer characteristics of high heat flux vapor chamber

Dongchuan MO, Shushen LU, Haoliang ZHENG, Chite CHIN,

《能源前沿（英文）》 2010年第4卷第2期页码 166-170 doi: 10.1007/s11708-009-0076-z

摘要： To meet the challenge of heat spreading in electronic products, highly efficient high heat flux heat transfer vapor chambers have been manufactured and their heat transfer characteristics have been studied by a fast test system. A solid copper block with the same shape as the vapor chamber is used to compare the performance of the vapor chamber. The result shows that, it will take about 5min to achieve a steady state in the fast test system. The heat transfer characteristics of the vapor chamber are more superior to those of the copper block. In this paper, total thermal resistance of the test system is used to evaluate the heat transfer characteristics of the vapor chamber, because it has already been used to consider both the spreading thermal resistance and the flatness of the vapor chamber.

关键词： high heat flux vapor chamber (VC) heat transfer characteristics fast test

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Preliminary design of an SCO conversion system applied to the sodium cooled fast reactor

《能源前沿（英文）》 2021年第15卷第4期页码 832-841 doi: 10.1007/s11708-021-0777-5

摘要： The supercritical carbon dioxide (SCO₂) Brayton cycle has become an ideal power conversion system for sodium-cooled fast reactors (SFR) due to its high efficiency, compactness, and avoidance of sodium-water reaction. In this paper, the 1200 MW_e large pool SFR (CFR1200) is used as the heat source of the system, and the sodium circuit temperature and the heat load are the operating boundaries of the cycle system. The performance of different SCO₂ Brayton cycle systems and changes in key equipment performance are compared. The study indicates that the inter-stage cooling and recompression cycle has the best match with the heat source characte-ristics of the SFR, and the cycle efficiency is the highest (40.7%). Then, based on the developed system transient analysis program (FR-Sdaso), a pool-type SFR power plant system analysis model based on the inter-stage cooling and recompression cycle is established. In addition, the matching between the inter-stage cooling recompression cycle and the SFR during the load cycle of the power plant is studied. The analysis shows that when the nuclear island adopts the flow-advanced operation strategy and the carbon dioxide flowrate in the SCO₂ power conversion system is adjusted with the goal of maintaining the sodium-carbon dioxide heat exchanger sodium side outlet temperature unchanged, the inter-stage cooling recompression cycle can match the operation of the SFR very well.

关键词： sodium-cooled fast reactor (SFR) supercritical carbon dioxide (SCO₂) brayton cycle load cycle

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EAP-FAST在公共无线局域网安全接入控制中的研究及实现

曹萍,裴文江

《中国工程科学》 2005年第7卷第12期页码 78-82

摘要：

Cisco公司于2004年提出基于隧道的灵活认证协议（EAP-FAST）以替代存在安全漏洞的LEAP认证协议，该协议具有安全性和易部署性的特点。文章论述了基于802.1x协议的EAP-FAST认证协议及其实现技术，并在公共无线局域网(PWLAN)综合实验平台上实现了EAP-FAST认证的客户端、认证者、认证服务器端功能。

关键词：公共无线局域网端口访问控制协议（802.1x）基于隧道的灵活认证协议（EAP-FAST）

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Identification of faults through wavelet transform vis-à-vis fast Fourier transform of noisy vibration

null

《机械工程前沿（英文）》 2014年第9卷第2期页码 130-141 doi: 10.1007/s11465-014-0298-6

摘要：

Fault diagnosis of rolling element bearings requires efficient signal processing techniques. For this purpose, the performances of envelope detection with fast Fourier transform (FFT) and continuous wavelet transform (CWT) of vibration signals produced from a bearing with defects on inner race and rolling element, have been examined at low signal to noise ratio. Both simulated and experimental signals from identical bearings have been considered for the purpose of analysis. The bearings have been modeled as spring-mass-dashpot systems and the simulated signals have been obtained considering transfer functions for the bearing systems subjected to impulsive loads due to the defects. Frequency B spline wavelets have been applied for CWT and a discussion on wavelet selection has been presented for better effectiveness. Results show that use of CWT with the proposed wavelets overcomes the short coming of FFT while processing a noisy vibration signals for defect detection of bearings.

关键词： Fault detection spline wavelet continuous wavelet transform fast Fourier transform

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“Fast Track” nasogastric decompression of rectal cancer surgery

Ka Li, Zongguang Zhou, Zengrong Chen, Yi Zhang, Cun Wang

《医学前沿（英文）》 2011年第5卷第3期页码 306-309 doi: 10.1007/s11684-011-0154-6

摘要： This study evaluates the application of fast track (FT) nasogastric decompression in patients who underwent anterior resection of rectal cancer. A randomized control trial was performed comparing the group with the fast track treatment ( =β57) and the group with traditional nasogastric decompression ( =β84). Preoperative characteristics and postoperative recovery indices were recorded and analyzed. The results indicate no significant differences in gender ( =β0.614), age ( =β0.653), tumor location ( =β0.113), and TNM stages ( =β0.054) were observed between the 2 groups. The differences in the type of resection, anastomosis, and adoption of protective colostomy were all not significant between the FT and the traditional group. During the first 24 hours after surgery, the volume of nasogastric drainage averaged 197 ml in the FT group and 155 ml in the traditional group ( =β0.197). The initiation of test-meal ( =β0.000), semiliquid diet ( =β0.002), and ordinary diet ( =β0.008) were all significantly shorter in the FT group. Furthermore, compared with the other group, the patients in the FT group enjoyed earlier removal of the abdominal drainage, urinary catheter, and shorter hospital stays ( =β0.000). Based on a correlation test, the duration of nasogastric decompression is related to the time of test-meal and semiliquid diet. The routine usage of nasogastric decompression in rectal surgery is unnecessary. The fast track procedure might help in facilitating postoperative functional and diet recovery, reducing the time of catheterization, and shortening hospital stay.

关键词： fast track nasogastric decompression rectal cancer surgery

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Investigation of vortical flows over oscillating body using fast Lagrangian vortex method

Baoshan ZHU ,

《能源前沿（英文）》 2009年第3卷第3期页码 297-306 doi: 10.1007/s11708-009-0010-4

摘要： A computational method facilitating long-time and high-resolution unsteady vortical flows is developed with the advantages of the discrete vortex methods. Both the velocity and pressure distribution of the flow field are calculated by integral formulations in combination with a fast summation algorithm. The vorticity field is described by Lagrangian representation, which is well suited to the moving boundary. Viscosity diffusion of the vorticity is considered with the core spreading model corrected by an adaptive splitting and merging algorithm. The effectiveness of the present method is examined by comparing the numerical results of unsteady separated flows which pass a cylinder and a thin cambered blade undergoing rotational oscillations with available experimental results. Interesting results about vortex shedding patterns and lock-in characteristics are provided for the thin cambered blade.

关键词： unsteady vortical flows fast vortex method vortex shedding rotational oscillation thin cambered blade

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A fast and accurate dynamic relaxation scheme

Mohammad REZAIEE-PAJAND, Mohammad MOHAMMADI-KHATAMI

《结构与土木工程前沿（英文）》 2019年第13卷第1期页码 176-189 doi: 10.1007/s11709-018-0486-2

摘要： Dynamic relaxation method (DRM) is one of the suitable numerical procedures for nonlinear structural analysis. Adding the fictitious inertia and damping forces to the static equation, and turning it to the dynamic system, are the basis of this technique. Proper selection of the DRM artificial factors leads to the better convergence rate and efficient solutions. This study aims to increase the numerical stability, and to decrease the analysis time. To fulfil this objective, the reduction rate of analysis error for consecutive iterations is minimized. Based on this formulation, a new time step is found for the viscous dynamic relaxation. After combining this novel relationship with the other DRM factors, various geometrical nonlinear structures, such as, trusses, frames and shells are analyzed. The obtained results verify the efficiency of authors’ scheme.

关键词： viscous dynamic relaxation time step displacement error geometric nonlinear analysis

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A fast antibiotic detection method for simplified pretreatment through spectra-based machine learning

《环境科学与工程前沿（英文）》 2022年第16卷第3期 doi: 10.1007/s11783-021-1472-9

摘要：

• A spectral machine learning approach is proposed for predicting mixed antibiotic.

关键词： Antibiotic contamination Spectral detection Machine learning

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动态快速路由查找算法

刘亚林

《中国工程科学》 2002年第4卷第7期页码 60-68

摘要：

给出了动态快速路由查找算法（DFR）的原理和实现。该算法采用特殊的数据结构来构建索引表，能支持动态插入、删除和更新路由；DFR算法最多4次访存，最少2次访存，就能找到完整的路由信息。该算法不仅适用于软件实现，而且由于查找简单，也适合于硬件实现。

关键词：前缀扩展 DFR 路由路由查找

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Multiscale stochastic finite element method on random field modeling of geotechnical problems – a fast

Xi F. XU

《结构与土木工程前沿（英文）》 2015年第9卷第2期页码 107-113 doi: 10.1007/s11709-014-0268-4

摘要： The Green-function-based multiscale stochastic finite element method (MSFEM) has been formulated based on the stochastic variational principle. In this study a fast computing procedure based on the MSFEM is developed to solve random field geotechnical problems with a typical coefficient of variance less than 1. A unique fast computing advantage of the procedure enables computation performed only on those locations of interest, therefore saving a lot of computation. The numerical example on soil settlement shows that the procedure achieves significant computing efficiency compared with Monte Carlo method.

关键词： multiscale finite element settlement perturbation random field geotechnical

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Catalytic fast pyrolysis of Kraft lignin with HZSM-5 zeolite for producing aromatic hydrocarbons

Xiangyu LI, Lu SU, Yujue WANG, Yanqing YU, Chengwen WANG, Xiaoliang LI, Zhihua WANG

《环境科学与工程前沿（英文）》 2012年第6卷第3期页码 295-303 doi: 10.1007/s11783-012-0410-2

摘要： Catalytic fast pyrolysis (CFP) of Kraft lignins with HZSM-5 zeolite for producing aromatics was investigated using analytical pyrolysis methods. Two Kraft lignins were fast pyrolyzed in the absence and presence of HZSM-5 in a Curie-point pyrolyzer. Without the catalyst, fast pyrolysis of lignin predominantly produced phenols and guaiacols that were derived from the subunits of lignin. However, the presence of HZSM-5 changed the product distribution dramatically. As the SiO /Al O ratio of HZSM-5 decreased from 200 to 25 and the catalyst-to-lignin ratio increased from 1 to 20, the lignin-derived oxygenates progressively decreased to trace and the aromatics increased substantially. The aromatic yield increased considerably as the pyrolysis temperature increased from 500°C to 650°C, but then decreased with yet further increase of pyrolysis temperature. Under optimal reaction conditions, the aromatic yields were 2.0 wt.% and 5.2 wt.% for the two lignins that had effective hydrogen indexes of 0.08 and 0.35.

关键词： lignin catalytic fast pyrolysis HZSM-5 zeolite aromatic hydrocarbon

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我国快堆技术发展的现状和前景

徐銤

《中国工程科学》 2008年第10卷第1期页码 70-76

摘要：

考虑到人口众多，经济快速发展，人民生活水平不断提高，人均能源相对贫乏和环境保护，国家已决策加快核能应用的发展。采用压水堆－快堆匹配闭式燃料循环达到核能供应的快速增长和可持续性的基本战略已经决定，也决定了分离和用快堆和ADS对高放废物（MA）的嬗变战略。笔者建议快堆工程发展将分三步进行，中国实验快堆（CEFR，65 MWt/20 MWe），中国原型/示范快堆（CEFR／CDFR,大于等于1 500 MWt/600 MWe）和中国经济验证性快增殖堆（CDFBR,1 000 MWt/1 500 MWe）。CPFR的设计研究已于2006年开始目前正处于安装、调试阶段，计划2009年首次临界。近期讨论建造比600 MWeCPFR更大功率的堆作为CDFR，以加速快堆商用的步伐。

关键词：快堆发展战略增殖堆燃烧堆中国实验快堆

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Structural parameter design method for a fast-steering mirror based on a closed-loop bandwidth

Guozhen CHEN, Pinkuan LIU, Han DING

《机械工程前沿（英文）》 2020年第15卷第1期页码 55-65 doi: 10.1007/s11465-019-0545-y

摘要： When a fast-steering mirror (FSM) system is designed, satisfying the performance requirements before fabrication and assembly is vital. This study proposes a structural parameter design approach for an FSM system based on the quantitative analysis of the required closed-loop bandwidth. First, the open-loop transfer function of the FSM system is derived. In accordance with the transfer function, the notch filter and proportional-integral (PI) feedback controller are designed as a closed-loop controller. The gains of the PI controller are determined by maximizing the closed-loop bandwidth while ensuring the robustness of the system. Then, the two unknown variables of rotational radius and stiffness in the open-loop transfer function are optimized, considering the bandwidth as a constraint condition. Finally, the structural parameters of the stage are determined on the basis of the optimized results of rotational radius and stiffness. Simulations are conducted to verify the theoretical analysis. A prototype of the FSM system is fabricated, and corresponding experimental tests are conducted. Experimental results indicate that the bandwidth of the proposed FSM system is 117.6 Hz, which satisfies the minimum bandwidth requirement of 100 Hz.

关键词： fast-steering mirror structural parameter PI controller bandwidth notch filter

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Task-space position/attitude tracking control of FAST fine tuning system

QI Lin, ZHANG Hui, DUAN Guanghong

《机械工程前沿（英文）》 2008年第3卷第4期页码 392-399 doi: 10.1007/s11465-008-0056-8

摘要： This paper addresses the task-space position/attitude tracking control of a suspended parallel robot, which is being developed in the framework of a five-hundred meter aperture spherical radio telescope (FAST) project. Based on the quaternion algebra, a novel model-independent task-space PD controller that ensures end-effector position and attitude tracking is presented. The simulation and experimental results show that the new controller has better control effects than the traditional joint-space controller.

关键词： telescope five-hundred end-effector controller simulation