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快速充电 2

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CP);符号间干扰(inter symbol interference, ISI);载波间干扰(inter carrier interference 1

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ICI);最大似然估计(maximum likelihood estimation 1

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交流永磁同步电机;滑模控制器;扩张状态观测器;鲁棒控制;运动控制 1

产业化 1

京沪铁路 1

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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    

Near-infrared fluorescent probe for fast track of cyclooxygenase-2 in Golgi apparatus in cancer cells

Bhaskar Gurram, Miao Li, Jiangli Fan, Jingyun Wang, Xiaojun Peng

《化学科学与工程前沿(英文)》 2020年 第14卷 第1期   页码 41-52 doi: 10.1007/s11705-019-1796-1

摘要: Cyclooxygenase-2 (COX-2) has been used as an excellent traceable biomarker, and exists maximally in Golgi apparatus (Cancer cells). Celecoxib (CCB) is a selective inhibitor for COX-2, and has been used as one of non-steroidal anti-inflammatory drug. Herein we report the conjugation of nile blue (NB) with CCB via a six-carbon linkage to form a fluorescence probe NB-C6-CCB for the detection of COX-2. NB-C6-CCB displays strong fluorescence with the emission peak centered at near-infrared wavelength (700 nm) in tumor cells or tumor tissues with high expression of COX-2. Importantly, NB-C6-CCB can discriminate cancer cells (MCF-7) fluorescence intensity from normal ones (COS-7) in the co-culture medium under confocal microscope. Subcellular localization of the NB-C6-CCB preferentially points to the Golgi apparatus and increases the fluorescent intensity. The competitive analysis (with CCB) and Native-PAGE analysis confirmed that NB-C6-CCB shows selective binding affinity towards COX-2 enzyme. Competitive analysis with CCB (flow cytometry assay) revealed the fluorescence intensity fluctuation due to pretreatment of CCB with different concentrations, indicating that the NB-C6-CCB is a precise or sensitive probe for the COX-2. Tumor tissue (depth: 500 µm), organs and mice imaging tests show excellent near-infrared visualization, specific localization and identification of tumors.

关键词: cyclooxygenase-2     nile blue     CCB     Golgi apparatus     NIR imaging    

Development of combined transitional pavement structure for urban tram track-road grade crossings

《结构与土木工程前沿(英文)》   页码 1199-1210 doi: 10.1007/s11709-023-0949-y

摘要: The grade crossings and adjacent pavements of urban trams are generally subjected to complex load conditions and are susceptible to damage. Therefore, in this study, a novel pavement structure between tram tracks and roads constructed using polyurethane (PU) elastic concrete and ultra-high-performance concrete (UHPC), referred to as a track-road transitional pavement (TRTP), is proposed. Subsequently, its performance and feasibility are evaluated using experimental and numerical methods. First, the mechanical properties of the PU elastic concrete are evaluated. The performance of the proposed structure is investigated using a three-dimensional finite element model, where vehicle-induced dynamic and static loads are considered. The results show that PU elastic concrete and the proposed combined TRTP are applicable and functioned as intended. Additionally, the PU elastic concrete achieved sufficient performance. The recommended width of the TRTP is approximately 50 mm. Meanwhile, the application of UHPC under a PU elastic concrete layer significantly reduces vertical deformation. Results of numerical calculations confirmed the high structural performance and feasibility of the proposed TRTP. Finally, material performance standards are recommended to provide guidance for pavement design and the construction of tram-grade crossings in the future.

关键词: urban tram track     grade crossing     combined track-road transitional pavement     polyurethane elastic concrete     finite element method    

客运专线无砟轨道铁路线下结构沉降变形观测与评估技术

李明领

《中国工程科学》 2009年 第11卷 第1期   页码 48-59

摘要:

为满足高速列车安全、舒适性的需要,保证线路的高平顺性,无碴轨道的铺设与运营对路基、桥涵、隧道等线下结构的工后沉降要求非常严格, 追求“零沉降”理念。以武广铁路客运专线为基础,系统地介绍了线下结构物沉降变形观测关键技术,数据管理与分析预测系统,提出了工后沉降的预测方法及评估条件与标准,合理确定无碴轨道开始铺设时间,以保证客运专线无碴轨道结构铺设的质量。并提出了一些体会和建议,为正在建设的无砟轨道客运专线提供借鉴。

关键词: 客运专线无砟轨道     沉降变形观测     分析评估     无碴轨道铺设条件    

风驰“电”掣,电动竞技赛车冲向未来

Mitch Leslie

《工程(英文)》 2023年 第24卷 第5期   页码 10-12 doi: 10.1016/j.eng.2023.03.003

XB高精度火箭橇试验滑轨

杨兴邦

《中国工程科学》 2000年 第2卷 第10期   页码 98-104

摘要:

火箭橇试验滑轨是一种大型地面动态模拟试验设备,用于研究试验件在空中高速度、高加速度运行时所遇到的诸多技术问题,其技术核心是一百万分之一的轨道直线性相对精度。它要求具有稳定的滑轨基础、高直线度准直基准线和光滑平顺的钢轨作为基本条件,需要采用钢轨精密机械加工、钢轨焊接、焊缝超声波探伤、轨道张拉锚固锁定、轨道直线度调整等新工艺技术。我国已成功地建成世界上唯一的、钢轨经精密机械加工后再全程焊接的XB高精度火箭橇试验滑轨。文章论述了它的诞生背景、设计思路、技术方案、技术与建造特点以及应用展望,该滑轨直线度达到世界先进水平。

关键词: 火箭滑橇     试验滑轨     地面动态模拟试验    

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 MWe 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    

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   

Liquid metal material genome: Initiation of a new research track towards discovery of advanced energy

Lei WANG, Jing LIU

《能源前沿(英文)》 2013年 第7卷 第3期   页码 317-332 doi: 10.1007/s11708-013-0271-9

摘要: As the basis of modern industry, the roles materials play are becoming increasingly vital in this day and age. With many superior physical properties over conventional fluids, the low melting point liquid metal material, especially room-temperature liquid metal, is recently found to be uniquely useful in a wide variety of emerging areas from energy, electronics to medical sciences. However, with the coming enormous utilization of such materials, serious issues also arise which urgently need to be addressed. A biggest concern to impede the large scale application of room-temperature liquid metal technologies is that there is currently a strong shortage of the materials and species available to meet the tough requirements such as cost, melting point, electrical and thermal conductivity, etc. Inspired by the Material Genome Initiative as issued in 2011 by the United States of America, a more specific and focused project initiative was proposed in this paper—the liquid metal material genome aimed to discover advanced new functional alloys with low melting point so as to fulfill various increasing needs. The basic schemes and road map for this new research program, which is expected to have a worldwide significance, were outlined. The theoretical strategies and experimental methods in the research and development of liquid metal material genome were introduced. Particularly, the calculation of phase diagram (CALPHAD) approach as a highly effective way for material design was discussed. Further, the first-principles (FP) calculation was suggested to combine with the statistical thermodynamics to calculate the thermodynamic functions so as to enrich the CALPHAD database of liquid metals. When the experimental data are too scarce to perform a regular treatment, the combination of FP calculation, cluster variation method (CVM) or molecular dynamics (MD), and CALPHAD, referred to as the mixed FP-CVM-CALPHAD method can be a promising way to solve the problem. Except for the theoretical strategies, several parallel processing experimental methods were also analyzed, which can help improve the efficiency of finding new liquid metal materials and reducing the cost. The liquid metal material genome proposal as initiated in this paper will accelerate the process of finding and utilization of new functional materials.

关键词: liquid metal material genome     energy material     material discovery     advanced material     room-temperature liquid alloy     thermodynamics     phase diagram    

非工程因素引发的高速铁路沉降问题及其对策探讨

尤昌龙

《中国工程科学》 2014年 第16卷 第2期   页码 106-112

摘要:

结合当前非工程因素引发的高速铁路线路沉降问题相关案例,分析了线路沉降超标产生的原因及其危害,归纳了相关问题类型,提出了解决问题的相关建议和意见,希冀有助于类似问题的解决。

关键词: 高速铁路     线路     非工程因素     非工程因素沉降    

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    

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    

客运专线轨道不平顺功率谱分析

陈秀方,金守华,曾华亮

《中国工程科学》 2008年 第10卷 第4期   页码 56-59

摘要:

轨道不平顺是车辆振动的主要激扰源,也是限制列车最高运行速度的主要因素之一,直接关系到列车运行的平稳性、安全性和舒适性。文章以秦沈客运专线轨检车实测轨道不平顺数据为统计样本,基于样本平稳性检验,采用FFT方法进行样本空间的谱估计,并由MATLAB编程得到轨道不平顺谱密度。基于轨道不平顺样本的总体平均,得出了谱密度频率平滑曲线和谱密度曲线拟合表达式,并与我国重载提速干线的谱密度曲线进行了对比分析。在此基础上,对秦沈客运专线的轨道状态进行了评估。

关键词: 客运专线     轨道不平顺     功率谱密度     平稳性检验    

高速铁路动车组在线路上适应性设计方法及应用

王开云,袁玄成,翟婉明

《中国工程科学》 2015年 第17卷 第4期   页码 90-97

摘要:

基于新一代中国高速列车(动车组)关键技术的研究发展趋势和策略问题进行详细讨论和技术展望。主要内容包括:首先,介绍国际先进轨道车辆制造商在其新一代车辆开发过程中采用的先进设计技术和理念,分层次研究其各自的核心技术特点和未来其可能的技术发展趋势。其次,在国内外文献研究的基础上,结合中国高速铁路车辆发展的自身特点和实际情况,针对具体的牵引传动技术、转向架技术、车体设计技术等可能面临的核心技术难题,提出一些分析建议。最后,在综合考虑轨道车辆造型发展趋势及设计原则的基础上,根据集成设计的理论与多学科优化设计方法,针对新一代中国高速铁路动车组可能面临的重大技术挑战与策略和改进措施的研究提出一些明确的建议。总之,通过本文的初步研究,希望可以对我国高速列车未来的发展方向和趋势提出一些有益的建议。

关键词: 高速铁路;线路适应性;动车组;车辆-轨道耦合动力学    

区域性沉降对高速铁路基础设施影响的研究

康高亮

《工程(英文)》 2016年 第2卷 第3期   页码 374-379 doi: 10.1016/J.ENG.2016.03.014

摘要:

本文对高速铁路线路基础沉降及差异沉降的主要影响因素进行了分析,提出局部地下水开采是影响线路差异沉降的直接诱因。通过对不同差异沉降量下无砟轨道附加荷载及高速行车过程中车辆、轨道和桥梁动力响应的研究,初步提出了运营期线路基础差异沉降控制标准。

关键词: 区域沉降     差异沉降     无砟轨道附加荷载     车辆&ndash     轨道动力学    

标题 作者 时间 类型 操作

Fast Track” nasogastric decompression of rectal cancer surgery

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

期刊论文

Near-infrared fluorescent probe for fast track of cyclooxygenase-2 in Golgi apparatus in cancer cells

Bhaskar Gurram, Miao Li, Jiangli Fan, Jingyun Wang, Xiaojun Peng

期刊论文

Development of combined transitional pavement structure for urban tram track-road grade crossings

期刊论文

客运专线无砟轨道铁路线下结构沉降变形观测与评估技术

李明领

期刊论文

风驰“电”掣,电动竞技赛车冲向未来

Mitch Leslie

期刊论文

XB高精度火箭橇试验滑轨

杨兴邦

期刊论文

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

期刊论文

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

期刊论文

Liquid metal material genome: Initiation of a new research track towards discovery of advanced energy

Lei WANG, Jing LIU

期刊论文

非工程因素引发的高速铁路沉降问题及其对策探讨

尤昌龙

期刊论文

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

null

期刊论文

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

Baoshan ZHU ,

期刊论文

客运专线轨道不平顺功率谱分析

陈秀方,金守华,曾华亮

期刊论文

高速铁路动车组在线路上适应性设计方法及应用

王开云,袁玄成,翟婉明

期刊论文

区域性沉降对高速铁路基础设施影响的研究

康高亮

期刊论文