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A high-accuracy DCO with hybrid architecture

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Journal of Semiconductors 2017年第7期38卷 111-116页

作者： Yapeng Sun Huidong Zhao Shushan Qiao Yong Hei fuhai zhang Collage of Electronic Information and Optical Engineering Nankai University Institute of Microelectronics Chinese Academy of Sciences

In this paper, a novel hybrid digital-controlled oscillator（DCO） is proposed, which is used to improve the accuracy of the all-digital clock generator without reference source. The DCO with hybrid architecture consists of two parts： DCO_high and DCO_low. The DCO_high decides the coarse output frequency of DCO, and adopts the cascade structure to decrease the area. The DCO_low adopts the chain structure with three-state buffer, and decides the fine output frequency of DCO. Compared with traditional cascade DCO, the proposed hybrid DCO features higher precision with less inherent delay. Therefore the clock generator can tolerate process, voltage and temperature（PVT） variation and meet the needs of different conditions. The DCO is designed in SMIC 180 nm CMOS process with 0.021 mm^2 chip area. The output frequency is adjusted from 15–120 MHz. The frequency error is less than 0.83% at 25 MHz with 1.6–1.8 V supply voltage and 0–80℃ temperature variations in TT, FF,SS corners.

关键词： high accuracy DCO all-digital PVT variations

Plant Nutrient Solution Detection System Based on ZigBee Wireless Technology

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Journal of Computer and Communications 2018年第6期6卷 61-68页

作者： Binyue Chen fuhai zhang Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin Tianjin China

Based on the limitations of traditional plant nutrient solution detection, a ZigBee plant nutrient solution detection system based on CC2530 was developed. This system uses CC2530 as the main control chip, DS18B20 as the temperature sensor for temperature acquisition, PH electrode sensor for PH value acquisition. The experiment shows that this wireless control system equipped with temperature and pH detection sensor collects and samples the main nutrient solution parameters through the main controller, performs wireless communication transmission and terminal communication, and realizes the intelligent detection of plant nutrient solution parameters. This technique of applying wireless sensor network technology to plant factories greatly improves the reliability and stability of the nutrient monitoring system.

关键词： Plant Nutrient Solution Detection System Wireless Sensor Technology ZigBee Embedded Web Server

Uncertainty Evaluation of Determination of Microcystin MC-LR in Environmental Samples by Solid Phase Extraction-Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

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Meteorological and Environmental Research 2016年第6期7卷 54-57页

作者： Zhao Bin zhang Min zhang fuhai Anhui Provincial Environmental Monitoring Center Station Hefei 230071 China

To assess uncertainty of determination of MC-LR in environmental samples by solid phase extraction- ultra performance liquid chromatography- tandem mass spectrometry,the sources of the uncertainty were evaluated firstly,and the expanded uncertainty was calculated *** results show that when MC-LR concentration in the water samples was 0.50 μg/L,the expanded uncertainty was 0.00628 μg/L(k=2).

关键词： Uncertainty Solid phase extraction Ultra performance liquid chromatography Tandem mass spectrometry Microcystin MC-LR China

Rapid Determination of Three Kinds of Microcystins in Environmental Water Samples by Disk SPE-Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

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Meteorological and Environmental Research 2016年第5期7卷 62-64,68页

作者： Zhao Bin zhang Min zhang fuhai Anhui Provincial Environmental Monitoring Center Station Hefei 230071 China

A method of rapidly detecting three kinds of microcystins( MCs) in environmental water samples by using disk SPE- ultra high performance liquid chromatography- tandem mass spectrometry( UPLC- MS / MS) was established. Firstly,environmental water samples were extracted by disk SPE column( C_(18)),and three kinds of MCs were separated by Waters BEH C_(18) chromatographic column with acetonitrile- 0. 2% formic acid solution as the mobile phase. After the gradient elution separation,the external standard method was used for quantitative and qualitative analysis under MRM of UPLC- MS / MS. The results showed that the three kinds of MCs in the range of 0. 05- 10 μg / L showed good linear relation,and the correlation coefficients were higher than 0. 999 4,while the method detection limit was 0. 04 ng / L. Under 0. 1,1,and 5 μg / L standard addition for the same environmental sample,the average recovery was 82. 8%- 108. 8%,and the relative standard deviation of determination results was2. 1%- 10. 1%( n = 6). This method is rapid,sensitive and accurate,so it can be effectively applied in the monitoring of MCs in environmental water samples.

关键词： Disk solid-phase extraction column Ultra performance liquid chromatography-tandem mass spectrometry Environmental water sample Microcystins Lake Chao China

Direction-Based Adaptive Switching Filter for Removing High-Density Impulse Noise

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Transactions of Tianjin University 2014年第6期20卷 422-428页

作者：刘会刚孙菁张福海任立儒 Tianjin Key Laboratory for Photo-Electronic Thin Film Devices and Technology College of Electronic Information and Optical Engineering Nankai University

A direction-based adaptive switching(DBAS) filter is presented for the removal of high-density impulse noise in images. The extrema detection and 28-directional detection are employed to discriminate the pixels as noisy or noise-free. If a pixel is classified as noisy, it will be replaced by a median or a mean value within an adaptive filter window with respect to different noise densities. Simulation results show that the miss-detection ratio and false-alarm ratio are both very low even at noise level as high as 90%. At the same time, better results are obtained in terms of the qualitative and quantitative measures. The peak signal-to-noise ratios increase by nearly 1 dB compared with other existing algorithms. In addition, the computation time is around 10 s for test images with resolutions of 512×512since the proposed approach has low complexity.

关键词： direction-based filter impulse noise noise detection nonlinear filter median filter

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利用谐声构拟上古音应该注意的几个问题

出土文献 2021年第1期 132-139,158页

作者：张富海复旦大学出土文献与古文字研究中心出土文献与中国古代文明研究协同创新中心

汉字的谐声是构拟上古音的重要材料,本文从三个方面讨论利用谐声构拟上古音应该注意的问题:一、《说文》的谐声标准过宽,其谐声分析多有不可信者,如“尼”“冀”“良”等字,需要做一番甄别工作;二、谐声材料是不同时代的累积,所谓谐声... 详细信息

汉字的谐声是构拟上古音的重要材料,本文从三个方面讨论利用谐声构拟上古音应该注意的问题:一、《说文》的谐声标准过宽,其谐声分析多有不可信者,如“尼”“冀”“良”等字,需要做一番甄别工作;二、谐声材料是不同时代的累积,所谓谐声时代早于《诗经》时代的说法不可信,利用谐声构拟上古音是可行的,但也应考虑到其中的异质成分;三、必须充分利用出土古文字中的谐声材料,作为《说文》谐声的补充。

关键词：上古音古文字谐声

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论海德格尔的“方言之家”

山东师范大学学报（人文社会科学版） 2011年第2期56卷 44-49页

作者：张福海山东师范大学文学院山东济南250014

海德格尔极为重视方言,他不但在方言中寻找着存在之思的来自方言语词的佐证和附释,而且还在存在的层面上,思考了方言的源初发生以及命运在方言中的显现。方言生成于"地带",而此一地带就是作为"之间"的命运。海德格尔认为,命运只有在方... 详细信息

海德格尔极为重视方言,他不但在方言中寻找着存在之思的来自方言语词的佐证和附释,而且还在存在的层面上,思考了方言的源初发生以及命运在方言中的显现。方言生成于"地带",而此一地带就是作为"之间"的命运。海德格尔认为,命运只有在方言的诗性言说中才能获得本真的呈现,因为方言具有本源的诗性,方言更能诗性地言说,能通过创生形象而庇护着命运的发生。方言植根于命运,同时命运又在方言中获得显现。由此,方言就是命运之家,命运又是方言之家。"方言之家"道说的就是命运与方言的这种两重性。

关键词：方言诗性命运

自由漂浮空间机器人回避动力学奇异的轨迹规划

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机器人 2012年第1期34卷 38-43页

作者：张福海付宜利王树国哈尔滨工业大学机器人技术与系统国家重点实验室黑龙江哈尔滨150080

针对非完整约束导致的自由漂浮空间机器人广义雅可比矩阵动力学奇异性问题,提出一种间接求解机器人逆运动学的方案.该方案通过运动方程分解并构造迭代函数,将动力学奇异转换为运动学奇异问题,避免直接求解逆广义雅可比矩阵,解决广义雅... 详细信息

针对非完整约束导致的自由漂浮空间机器人广义雅可比矩阵动力学奇异性问题,提出一种间接求解机器人逆运动学的方案.该方案通过运动方程分解并构造迭代函数,将动力学奇异转换为运动学奇异问题,避免直接求解逆广义雅可比矩阵,解决广义雅可比矩阵动力学参数相关特性问题,仿真结果表明该方法能够有效地实现自由漂浮空间机器人回避动力学奇异的非完整轨迹规划.

关键词：自由漂浮空间机器人动力学奇异非完整轨迹规划

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改良膨胀土施工技术与改良土的性质研究

岩石力学与工程学报 2006年第z1期25卷 3157-3161页

作者：王保田张福海张文慧河海大学岩土工程研究所江苏南京210098

黄淮河冲积平原区广泛分布弱～中等膨胀土,用这种土作为高等级公路路堤填筑材料时,必须用掺石灰的方法对土体进行改良,以提高土体的强度,降低土体的胀缩性。改良膨胀土施工采用二次掺灰工艺、合适的石灰拌和方法和碾压机械组合对提高改... 详细信息

黄淮河冲积平原区广泛分布弱～中等膨胀土,用这种土作为高等级公路路堤填筑材料时,必须用掺石灰的方法对土体进行改良,以提高土体的强度,降低土体的胀缩性。改良膨胀土施工采用二次掺灰工艺、合适的石灰拌和方法和碾压机械组合对提高改良土的碾压质量很重要。系列现场和室内试验研究表明:采用二次拌灰工艺能够使石灰均匀并易于碾压。尽管压实天然土的CBR强度不满足规范的要求,但改良土的CBR强度高,自由膨胀率低,无压膨胀量小。改良土的微观结构与天然土明显不同,土粒间连接增强,基本看不到单粒形态。

关键词：土力学公路路基改良膨胀土掺灰量 CBR强度微观结构