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一种石油生产多分相检测新型光纤传感器 被引量:3
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作者 陈基亮 孔德明 +3 位作者 郝虎 孔德瀚 刘国权 孔令富 《计量学报》 CSCD 北大核心 2022年第8期1036-1043,共8页
为解决石油生产多分相检测问题,研制了一种用于多分相检测的新型双接收端光纤传感器(NDR-FOP),利用ZEMAX光线追迹方法构建了双接收端环形耦合光路(DR-RCOP)模型。对通过NDR-FOP锥形敏感头的光线传输轨迹进行了数学描述与仿真分析。基于... 为解决石油生产多分相检测问题,研制了一种用于多分相检测的新型双接收端光纤传感器(NDR-FOP),利用ZEMAX光线追迹方法构建了双接收端环形耦合光路(DR-RCOP)模型。对通过NDR-FOP锥形敏感头的光线传输轨迹进行了数学描述与仿真分析。基于研究结果,对油气水多相流混相介质中NDR-FOP多分相检测性能进行了评价以及在实验平台上进行了测试研究,仿真与实验结果均表明:油气水介质之间的差特征值形成了明显的间距,NDR-FOP多分相检测是可行和有效的。 展开更多
关键词 计量学 分相检测 双接收端光纤传感器 ZEMAX光线追迹 耦合光路
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三相不平衡负载瞬时无功电流分相检测方法 被引量:5
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作者 许杏桃 徐小康 +1 位作者 陈群 黄文静 《电器与能效管理技术》 2018年第19期52-57,共6页
目前,基于瞬时无功功率理论的各种检测方法由于具有较强的实时性而获得广泛的应用,但此类方法难以实现三相不平衡负载无功电流的分相检测。提出了一种基于电压基准分相同步的瞬时无功电流分相检测方法。首先分析了传统瞬时无功电流检测... 目前,基于瞬时无功功率理论的各种检测方法由于具有较强的实时性而获得广泛的应用,但此类方法难以实现三相不平衡负载无功电流的分相检测。提出了一种基于电压基准分相同步的瞬时无功电流分相检测方法。首先分析了传统瞬时无功电流检测方法在不平衡负荷无功电流检测中存在的问题。然后,系统阐述了所提方法的基本原理及其具体实现,并且通过典型案例对所提方法开展了进一步分析与论证。最后,对所提方法进行了仿真分析与验证。理论分析和仿真结论表明:所提瞬时无功电流检测方法能够实时、精确地实现对三相不平衡负荷瞬时无功电流的分相检测。 展开更多
关键词 不平衡负荷 瞬时无功电流 分相检测 电压分相同步
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压缩感知在ECT分相含率检测中的应用
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作者 唐晨晖 胡红利 +1 位作者 王格 张肖 《西北大学学报(自然科学版)》 CAS CSCD 北大核心 2019年第5期698-704,共7页
该文研究了压缩感知(CS)理论在电容层析成像(ECT)问题中的应用,有效解决了图像重构中的欠定性问题,从而通过图像计算两相流中的截面分相含率。首先,采用时域基作为图像向量的稀疏基,并采用高斯随机对灵敏度矩阵进行重新排序,设计其观测... 该文研究了压缩感知(CS)理论在电容层析成像(ECT)问题中的应用,有效解决了图像重构中的欠定性问题,从而通过图像计算两相流中的截面分相含率。首先,采用时域基作为图像向量的稀疏基,并采用高斯随机对灵敏度矩阵进行重新排序,设计其观测矩阵;然后,将不动点迭代算法FPC应用于凸优化问题的求解,得到重构图像;最后,利用最优阈值算法对重构图像进行灰度处理,由灰度图像进行分相含率的计算。在仿真实验阶段建立ECT传感器模型,对3种典型两相流流型进行重构,并与经典的LBP,Landweber算法综合3种重构效果评价指标进行比较。仿真结果表明:基于CS的ECT重构算法在只有少量测量数据的情况下也能精确地重构图像,且成像质量远高于LBP算法,并优于Landweber迭代算法,成像速度也大幅提升,有效提高了分相含率检测的准确性。 展开更多
关键词 电容层析成像 分相含率检测 压缩感知理论 不动点连续算法
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油田钢质常压储罐内腐蚀挂片检测及腐蚀机理研究 被引量:6
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作者 龙媛媛 刘晶姝 +2 位作者 刘瑾 谭晓林 杨为刚 《石油化工腐蚀与防护》 CAS 2018年第1期16-19,共4页
对胜利油田两个典型区块的各一个原油沉降罐进行了淤泥相、水相、水油界面、油相、油气界面和气相共计6个层位的内腐蚀挂片,利用挂片质量损失法对腐蚀速率进行了定量测试,并通过挂片腐蚀产物X射线衍射分析,研究了腐蚀机理,结果表明:不... 对胜利油田两个典型区块的各一个原油沉降罐进行了淤泥相、水相、水油界面、油相、油气界面和气相共计6个层位的内腐蚀挂片,利用挂片质量损失法对腐蚀速率进行了定量测试,并通过挂片腐蚀产物X射线衍射分析,研究了腐蚀机理,结果表明:不同区块储罐、同一储罐不同层位的腐蚀速率和腐蚀机理存在明显差异,对全面了解储罐腐蚀现状、及时发现安全隐患并有针对性地进行腐蚀防护和腐蚀治理具有指导意义。 展开更多
关键词 常压储罐 分相区挂片检测 腐蚀速率 腐蚀机理 对比分析
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一种新型高压带电监测系统的设计与实现 被引量:7
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作者 顾金凤 唐炜 《电测与仪表》 北大核心 2005年第6期54-57,5,共5页
在电力行业中,防止电气误操作是一个十分重要的问题。介绍了一种基于89C51的新型高压带电监测系统,其中采用了非接触式传感器、分相检测、液晶显示、强制闭锁、远程实时监控等新技术。实践表明,该系统安全可靠、人机界面友好、操作简便... 在电力行业中,防止电气误操作是一个十分重要的问题。介绍了一种基于89C51的新型高压带电监测系统,其中采用了非接触式传感器、分相检测、液晶显示、强制闭锁、远程实时监控等新技术。实践表明,该系统安全可靠、人机界面友好、操作简便,适宜在电力行业中进行推广应用。 展开更多
关键词 单片机 高压线路 带电状态 分相检测 远程通讯
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NEW METHOD FOR WHITE BLOOD CELL DETECTION BASED ON RELEVANCE VECTOR MACHINE
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作者 王敏 乔立山 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第3期269-274,共6页
A new method for the white blood cell (WBC) detection is presented based on the relevance vector machine (RVM). Firstly,the sparse relevance vectors (RVs) are obtained while fitting the 1-D histogram by RVM. The... A new method for the white blood cell (WBC) detection is presented based on the relevance vector machine (RVM). Firstly,the sparse relevance vectors (RVs) are obtained while fitting the 1-D histogram by RVM. Then,the needed threshold value is directly selected from these limited RVs. Finally,the entire connective WBC regions are segmented from the original image. The method is used for the WBC detection. It reduces the interference induced by the illumination and the staining. It has advantages of the high computation efficiency and the no extra parameter setting. Experimental results demonstrate good performances of the method. 展开更多
关键词 image segmentation detectors white blood cell detection relevance vector machine
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BLIND ADAPTIVE MULTIUSER DETECTOR FOR NONLINEARLY MODULATED SATELLITE MOBILE CDMA SYSTEMS 被引量:2
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作者 Shao Shixiang Yang Longxiang Kyungsup Kwak 《Journal of Electronics(China)》 2006年第3期338-340,共3页
This paper presents a novel blind adaptive noncoherent decorrelative multiuser detector for nonlinearly modulated satellite mobile Code Division Multiple Access (CDMA) systems. By using the known signature waveforms o... This paper presents a novel blind adaptive noncoherent decorrelative multiuser detector for nonlinearly modulated satellite mobile Code Division Multiple Access (CDMA) systems. By using the known signature waveforms of the counterpart earth station in the blind adaptive multiuser detector, the system performance has been improved obviously. The computation results about the convergence properties of the new detector and the previous detectors demonstrate that the proposed multiuser detector has better performance than previous multiuser detectors for nonlinearly modulated CDMA systems. 展开更多
关键词 Mobile satellite communication Nonlinear Code Division Multiple Access (CDMA) system Noncoherent detection Multiuser detection
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A method for constraining the end effect of EMD based on sequential similarity detection and adaptive filter 被引量:2
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作者 Wei Dongdong Tang Wencheng 《Journal of Southeast University(English Edition)》 EI CAS 2021年第1期14-21,共8页
Aimed at the problem of the end effect when using empirical mode decomposition(EMD),a method for constraining the end effect of EMD is proposed based on sequential similarity detection and adaptive filter.The method d... Aimed at the problem of the end effect when using empirical mode decomposition(EMD),a method for constraining the end effect of EMD is proposed based on sequential similarity detection and adaptive filter.The method divides the signal into many wavelets,and it changes the initial wavelet length to select the best initial wavelet that has the minimum error and maximum number of matching seed wavelets,and the wavelet slopes are used for pre-matching and secondary matching to speed up the matching speed.Then,folded self-adaptive threshold is used to select multiple seed wavelets,and finally the end waveform is predicted and expanded according to the adaptive filter method.The proposed method is used to analyze the non-stationary nonlinear simulation signal and experimental signal,and it is compared with the mirror extension and RBF extension methods.The orthogonality index and similarity index of the EMD results of the extended signal after the proposed method are better than those of the other methods.The results show that the proposed method can better constrain the end effect,and has certain validity,accuracy and stability in solving the end effect problem. 展开更多
关键词 empirical mode decomposition(EMD) end effect sequential similarity detection adaptive filter
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Assessment of Triazine Herbicides in Soil by Microwave-assisted Extraction Followed by Gas Chromatography Coupled to Mass Spectrometry Detection 被引量:1
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作者 Darlan Ferreira Silva Maria Diva Landgraf Maria Olimpia Oliveira Rezende 《Journal of Chemistry and Chemical Engineering》 2017年第1期1-8,共8页
An alternative and fast method for the analysis of a mixture of nine triazines herbicides in soil is presented. The method is based on MAE (microwave-assisted extraction) of herbicides using ethyl acetate as extract... An alternative and fast method for the analysis of a mixture of nine triazines herbicides in soil is presented. The method is based on MAE (microwave-assisted extraction) of herbicides using ethyl acetate as extractant. The economy in the use of solvents coupled with the decrease in extraction time and lower power consumption make MAE a technique that meets the principles of green chemistry. MAE operational parameters, extraction time, mass of the sample and extraction temperature, were optimized by RSM (response surface methodology). Determination of analytes was completed using gas chromatograph coupled to mass spectrometry detection. The selected triazines could be efficiently extracted by the solvent at 80 ℃ for 10 min, with 80% output of maximum power. When the optimized method was applied to analysis samples, the recoveries of analytes ranged from 81.8 to 106.0% and relative standard deviations were lower than 8.41%. The method is stable and reasonable, which can be used for the determination of ninetriazine herbicides residues in soil. 展开更多
关键词 Factorial design response surface methodology microwave-assisted extraction HERBICIDES triazines.
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Determination of the gas compositions for direct coal liquefaction by gas chromatography 被引量:1
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作者 Xiao-Man ZHU Pei-Lin LI Shu-Feng DU 《Journal of Coal Science & Engineering(China)》 2013年第4期535-539,共5页
Via multi-dimensional gas chromatography, configured with parallel dual-channel, double detectors, valves switching and back flushing, rapid analysis of the gas compositions consisting of C1-C5 hydrocarbons and perman... Via multi-dimensional gas chromatography, configured with parallel dual-channel, double detectors, valves switching and back flushing, rapid analysis of the gas compositions consisting of C1-C5 hydrocarbons and permanent gases, such as CO2, H2S, H2, and CO, for direct coal liquefaction has been realized. With four packed chromatographic columns, which are Hayesep-Q pre-column, Hayesep-Q column, molecular sieve 5A column and one PLOT A1203 S capillary column, the gas compositions for direct coal liquefaction are analyzed qualitatively and quantitatively by the external standard method. The determination method has such advantages as excellent separation, simple operation, rapid analysis and accurate results. 展开更多
关键词 gas chromatography gas compositions direct coal liquefaction external standard method
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Lignin in Marine Environment and Its Analysis-A Review
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作者 LI Xianguo ZHANG Ting +2 位作者 SUN Shuwen LAN Haiqing YU Tao 《Journal of Ocean University of China》 SCIE CAS 2012年第4期501-506,共6页
Lignin is a group of phenolic polymers which is abundant in the woody tissues of vascular plants,and is essentially absent from all other living organisms.It has therefore been accepted as a tracer for terrestrial org... Lignin is a group of phenolic polymers which is abundant in the woody tissues of vascular plants,and is essentially absent from all other living organisms.It has therefore been accepted as a tracer for terrestrial organic carbon(TOC) in marine environment since the 1970s.Lignin polymers are not amenable to direct chemical analysis without prior isolation.This review focused on the methods of chemical decomposition,extraction,derivatization and detection of lignin in marine environment.We described and compared several chemical decomposition methods,including nitrobenzene oxidation,alkaline cupric oxide(CuO) oxidation and thermochemolysis,and detection methods such as gas chromatography(GC),gas chromatography-mass spectrometry(GC-MS),high performance liquid chromatography(HPLC) and so on.Possible improvement of lignin analysis and the application prospects of this tracer were also discussed. 展开更多
关键词 lignin in marine environment DECOMPOSITION EXTRACTION DERIVATIZATION detection
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Multiple phase detector of M-ary phase shift keying symbols in code division multiple access systems 被引量:1
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作者 QUAN Zhi 《Journal of Central South University》 SCIE EI CAS 2011年第4期1080-1086,共7页
A novel iterative technique, the phase descent search detection was proposed. This technique constrained the solution (PDS) algorithm, for M-ary phase shift keying (M-PSK) symbols to have a unit magnitude and it w... A novel iterative technique, the phase descent search detection was proposed. This technique constrained the solution (PDS) algorithm, for M-ary phase shift keying (M-PSK) symbols to have a unit magnitude and it was based on coordinate descent iterations where coordinates were the unknown symbol phases. The PDS algorithm, together with a descent local search (also implemented as a version of the PDS algorithm), was used multiple times with different initializations in a proposed multiple phase detector; the solution with the minimum cost was then chosen as the final solution. The simulation results show that for highly loaded multiuser scenarios, the proposed technique has a detection performance that is close to the single-user bound. The results also show that the multiple phase detector allows detection in highly overloaded scenarios and it exhibits near-far resistance. In particular, the detector has a performance that is significantly better, and complexity that is significantly lower, than that of the detector based on semi-definite relaxation. 展开更多
关键词 coordinate descent COMPLEXITY M-ary phase shift keying (M-PSK) multiuser detection quadratic optimization semi-definite relaxation
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Simultaneous quantification of lopinavir and ritonavir in human plasma by high performance liquid chromatography coupled with UV detection 被引量:1
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作者 KOU HuiJuan YE Min +5 位作者 FU Qiang HAN Yang DU XiaoLi XIE Jing ZHU Zhu LI TaiSheng 《Science China(Life Sciences)》 SCIE CAS 2012年第4期321-327,共7页
High performance liquid chromatography was coupled with UV detection for simultaneous quantification of lopinavir (LPV) and ritonavir (RTV) in human plasma. This assay was sensitive, accurate and simple, and only ... High performance liquid chromatography was coupled with UV detection for simultaneous quantification of lopinavir (LPV) and ritonavir (RTV) in human plasma. This assay was sensitive, accurate and simple, and only used 200μL of plasma sample. Samples were liquid-liquid extracted, and diazepam was used as an internal standard. The chromatographic separation was achieved on a C18 reversed-phase analytic column with a mobile phase of acetonitrile-sodium dihydrogen phosphate buffer (10 mmol L-1, pH 4.80) (60:40, v/v). UV detection was conducted at 205 nm and the column oven was set at 40℃. Calibration curves were constructed between 0,5-20 μg mL-1 for LPV and 0.05-5 μg mL-1 for RTV. The relative standard deviations were 2.16%-3.20% for LPV and 2.12%-2.60% for RTV for intra-day analysis, and 2.34%-4.04% for LPV and 0.31%-4.94% for RTV for inter-day analysis. The accuracy was within 100%+10%. The mean extraction recoveries were 79.17%, 52.26% and 91.35% for RTV, LPV and diazepam, respectively. This method was successfully applied to human plasma samples from patients orally administered a salvage regimen of lopinavir-ritonavir tablets. 展开更多
关键词 LOPINAVIR ritonavir HPLC UV detection human plasma
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Performance analysis of microcantilever array sensing 被引量:2
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作者 ZHOU XiaRong LIU Hong +2 位作者 WU ShangQuan ZHANG QingChuan WU XiaoPing 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2017年第11期1674-1680,共7页
Array sensing is increasingly important in the development of microcantilever(MC) sensors, and response consistency is the foundation for MC array sensing. In the present work, we investigated the response consistency... Array sensing is increasingly important in the development of microcantilever(MC) sensors, and response consistency is the foundation for MC array sensing. In the present work, we investigated the response consistency of MC array sensing. The responses of two types of commercially available MC arrays were studied under conditions of temperature change, solution replacement and biochemical molecular interaction. For the thermal response, the deflections of both arrays were found to be proportional to temperature, and the responses of the MCs in both arrays were consistent with each other. The thermal response sensitivity for each MC during temperature increase and decrease also showed good consistency. Moreover, the MC array showed good consistency for the response induced by solution replacement. Finally, we also demonstrated that the MC array had good consistency in biochemical detection, exemplified by aflatoxin antibody-anti gen binding. The good response consistency makes this technology reliable and accurate for biochemical sensing. 展开更多
关键词 microcantilever array thermal response environmental disturbance biochemical detection
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Nearly deterministic quantum Fredkin gate based on weak cross-Kerr nonlinearity
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作者 吴运祥 朱畅华 裴昌幸 《Optoelectronics Letters》 EI 2016年第5期395-397,共3页
A scheme of an optical quantum Fredkin gate is presented based on weak cross-Kerr nonlinearity. By an auxiliary coherent state with the cross-Kerr nonlinearity effect, photons can interact with each other indirectly, ... A scheme of an optical quantum Fredkin gate is presented based on weak cross-Kerr nonlinearity. By an auxiliary coherent state with the cross-Kerr nonlinearity effect, photons can interact with each other indirectly, and a non-demolition measurement for photons can be implemented. Combined with the homodyne detection, classical feedforward, polarization beam splitters and Pauli-X operations, a controlled-path gate is constructed. Furthermore, a quantum Fredkin gate is built based on the controlled-path gate. The proposed Fredkin gate is simple in structure and feasible by current experimental technology. 展开更多
关键词 nonlinearity coherent interact deterministic auxiliary Pauli trapped gates operations feasible
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