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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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Fast detection algorithm for cracks on tunnel linings based on deep semantic segmentation

《结构与土木工程前沿（英文）》 2023年第17卷第5期页码 732-744 doi: 10.1007/s11709-023-0965-y

摘要： An algorithm based on deep semantic segmentation called LC-DeepLab is proposed for detecting the trends and geometries of cracks on tunnel linings at the pixel level. The proposed method addresses the low accuracy of tunnel crack segmentation and the slow detection speed of conventional models in complex backgrounds. The novel algorithm is based on the DeepLabv3+ network framework. A lighter backbone network was used for feature extraction. Next, an efficient shallow feature fusion module that extracts crack features across pixels is designed to improve the edges of crack segmentation. Finally, an efficient attention module that significantly improves the anti-interference ability of the model in complex backgrounds is validated. Four classic semantic segmentation algorithms (fully convolutional network, pyramid scene parsing network, U-Net, and DeepLabv3+) are selected for comparative analysis to verify the effectiveness of the proposed algorithm. The experimental results show that LC-DeepLab can accurately segment and highlight cracks from tunnel linings in complex backgrounds, and the accuracy (mean intersection over union) is 78.26%. The LC-DeepLab can achieve a real-time segmentation of 416 × 416 × 3 defect images with 46.98 f/s and 21.85 Mb parameters.

关键词： tunnel engineering crack segmentation fast detection DeepLabv3+ feature fusion attention mechanism

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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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基于沃尔什特征的增强型AdaBoost 人脸快速检测算法

郭志波,杨静宇,刘华军,严云洋

《中国工程科学》 2008年第10卷第7期页码 125-131

摘要：

提出一种基于沃尔什特征的增强型AdaBoost 人脸快速检测算法，不仅具有很快的训练速度，而且利用较少的非人脸样本进行训练就可以达到较好的检测效果。首先，提出用较少的沃尔什特征来代替大量的 Harr-Like 特征可以较大幅度的降低特征之间的冗余。然后提出一种双阈值增强型AdaBoost 算法，其中双阈值的快速搜索方法大大节约了训练时间，并且在训练Cascaded 检测器过程中，前层分类器的训练结果对后层分类器的训练具有指导作用，加强了总体检测器的性能，另外通过各层分类器阈值的调节，能够将人脸和非人脸的训练结果尽量分离。最后，使用该算法训练的检测器对MIT＋CMU 人脸测试库进行了测试，结果表明该方法在训练速度、测试精度、检测时间等方面都优于相应的方法。

关键词：沃尔什特征增强型AdaBoost Cascaded 型检测器人脸检测

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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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一种快速精确触觉碰撞检测中接触细节层次控制方法 Article

A Ram CHOI, Sung Min KIM, Mee Young SUNG

《信息与电子工程前沿（英文）》 2017年第18卷第8期页码 1117-1130 doi: 10.1631/FITEE.1500498

摘要：为实现精确稳定的触觉再现，包围体积（球体、轴对称包围盒、定向包围盒或多面体）必须尽可能紧密地填充或覆盖目标对象，来完成交互式触觉应用中的碰撞检测。本文提供了一种方法，用于创建与接触细节层次（contact levels of details, CLOD）相关的包围球体。该球体与目标对象相配合的同时，还能平衡碰撞检测的速度与精确性。所提出的方法主要包括包围球体成形以及两级碰撞检测两部分。进一步说，包围球体成形可分为2步：创建球体和聚类球体；两级碰撞检测也包括2个阶段：球体的快速检测以及精确检测。首先，通过包围球体的创建实现球体碰撞检测中的初始快速探测。一旦探测到碰撞，可通过检查碰撞边界内网格与触觉点的间距来实现更精确的检测效果。为实现这种精细层级的检测，需要定义一种特殊的包围体积数据结构来囊括球体内的全部网格信息。我们通过一系列实现检验了所提出方法的有效性和性能表现，结果表明所提出算法的速度和精确度可以满足触觉仿真的需要。通过球体聚类来保证检测速度，通过基于体素的直接碰撞检测来保证检测精确度。通过基于距离的聚类，所提出的方法在CLOD方面仍保持了其独创性。

关键词：碰撞检测；触觉再现；包围球体；聚类；接触细节层次

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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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基于位置旋转变换和非均匀快速傅立叶变换的机动目标高效相参检测 Research Articles

靳科1,赖涛2,齐艳丽3,黄洁1,赵拥军1

《信息与电子工程前沿（英文）》 2020年第21卷第8期页码 1251-1266 doi: 10.1631/FITEE.1900272

摘要：长时间相参积累能够显著提升雷达对机动目标的检测和运动参数估计性能。然而，相参积累期间目标的线性距离徙动、二次距离徙动和多普勒频率徙动将导致检测性能急剧下降。提出基于位置旋转变换和非均匀快速傅里叶变换的高效稳健相参积累方法。首先，利用二阶Keystone变换消除二次距离徙动。然后，利用旋转角度和多普勒频率之间的对应关系，构建相位补偿函数，从而利用位置旋转和非均匀快速傅里叶变换实现高效的参数估计。与现有代表性算法相比，所提算法能以较低运算复杂度实现近乎理想的检测性能。最后，基于雷达实测数据的实验证明所提算法有效。

关键词：相参积累；机动目标；参数估计；位置旋转变换；非均匀快速傅立叶变换

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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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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