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Construction of a New Model of Contactless Medical Services for Outpatients Based on the Project-Achieving Quality Control Circle 被引量:1
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作者 Shuang Chen Zhihong Gao +1 位作者 Xiaoxia Huang Zhiqin Yin 《Journal of Clinical and Nursing Research》 2023年第4期29-37,共9页
Objective: To carry out empirical research on the role of project-achieving quality control circle (QCC) in constructing a new model of contactless medical service for outpatients. Methods: A QCC, consisting of inform... Objective: To carry out empirical research on the role of project-achieving quality control circle (QCC) in constructing a new model of contactless medical service for outpatients. Methods: A QCC, consisting of information office members from a grade A tertiary hospital in Wenzhou, was established to conduct a research project with the theme “Constructing a new model of contactless medical service based on outpatients’ experience.” According to the ten steps and PDCA cycle, an analysis was carried out before and after the QCC activities, focusing on improving pre-consultation services, providing steward-like services, and facilitating post-consultation management. Results: After the QCC activities, the mobile appointment rate, missed appointment rate, the proportion of smart check-ins, and the average check-in time were 55.68%, 4.02%, 39.75%, and 8.24 ± 3.66 min, respectively;in contrast, before the activities, they were 32.00%, 7.88%, 0.00%, and 14.96 ± 4.98 min, respectively;the difference between the two groups was statistically significant (χ2 = 3480.112, 4994.496;Fisher’s exact probability = 963788.570;t = 5.323, P < 0.001). Many experts have also visited the hospital to learn about this system, thus rendering social and economic benefits. Conclusion: Project-achieving QCC activities are suitable for complex situations, such as constructing a new model of contactless medical service, and can significantly improve outpatient service quality, enhance patients’ experience, and improve the abilities of circle members. 展开更多
关键词 Quality control circle Project-achieving Outpatient contactless medical service Patient experience
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Modelling and Parameters Identification of Through-Hole Type Wind Turbine Contactless Sliprings
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作者 Ali Abdolkhani Aiguo Patrick Hu Nirmal C.-K. Nair 《Engineering(科研)》 2012年第5期272-283,共12页
This paper presents a modelling and parameter identification of through-hole type contactless slipring systems for transferring electrical power for wind turbine pitch control. An equivalent circuit model has been dev... This paper presents a modelling and parameter identification of through-hole type contactless slipring systems for transferring electrical power for wind turbine pitch control. An equivalent circuit model has been developed from the physical structure and dimensions of the contactless slipring using the duality rules, which is very different form traditional transformer. The circuit inductances are determined by the derived expressions from the system reluctances. In particular, the equivalent resistance representing the core loss of the slipring has been determined using phasor diagram of exciting current. FEM (Finite Element Method) models and practical prototypes are developed for testing and verifycations. Both simulation and experimental results have shown that the developed model gives truthful values for numerical calculations in order to obtain the equivalent electric circuit. The effect of fringing flux around the air gap on mutual inductance and the ways of correcting its effects are analysed. The obtained values have shown that the developed models and derived equations are with high accuracy as compared to the FEM simulation and experimental results. 展开更多
关键词 CSS (contactless Slipring Systems) Transformer Modeling contactless Power Transfer WIND TURBINE PITCH Control
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Analysis of arecoline in Semen Arecae decoction pieces by microchip capillary electrophoresis with contactless conductivity detection 被引量:2
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作者 Zi-You Cai Yong-Chong Li +1 位作者 Li-Hua Li Zuan-Guang Chen 《Journal of Pharmaceutical Analysis》 CAS 2012年第5期356-360,共5页
A new method for the determination of arecoline in Semen Arecae decoction pieces by microchip capillary electrophoresis with contactless conductivity detection (MCE-CCD) was proposed. The effects of various electrop... A new method for the determination of arecoline in Semen Arecae decoction pieces by microchip capillary electrophoresis with contactless conductivity detection (MCE-CCD) was proposed. The effects of various electrophoretic operating parameters on the analysis of arecoline were studied. Under the optimal conditions, arecoline was rapidly separated and detected in 1 rain with good linearity over the concentration range of 20 1500 uM (r2=0.9991) and the detection limit of 5 uM (S/N=3). The method was used for the analysis of arecoline satisfactorily with a recovery of 96.8 -104%. 展开更多
关键词 Microchip capillary electrophoresis contactless conductivity detection ARECOLINE Semen Arecae
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Study on contactless ultrasonic sensor and seam tracking 被引量:2
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作者 Hou Wenkao Hu Shengsun and Zhao Jiarui Tianjin University Zhang Shaobin (Qing Hua University,Beijing) 《China Welding》 EI CAS 1995年第1期51-56,共6页
The sensitivity of contactless ultrasonic sensor is improved from 3.3% to 26% through acoustic and electric matching technique in this paper.Along dual crest lines auto seam tracking is firstly realized with contactle... The sensitivity of contactless ultrasonic sensor is improved from 3.3% to 26% through acoustic and electric matching technique in this paper.Along dual crest lines auto seam tracking is firstly realized with contactless ultrasonic sensing.The focused acoustic lens is accurately designed, and a sonic beam with 0.5 mm in diameter is achieved. By means of software and hardware technique the accuracy of seam tracking with ultrasonic sensing is 0.5 mm in lateral direction and 0.2 mm in longitudinal direction respectively. 展开更多
关键词 ultrasonic sensor contactless seam tracking arc welding
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Wireless contactless pressure measurement of an LC passive pressure sensor with a novel antenna for high-temperature applications 被引量:1
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作者 李晨 谭秋林 +3 位作者 薛晨阳 张文栋 李运芝 熊继军 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第4期540-545,共6页
In this paper, a novel antenna is proposed for high-temperature testing, which can make the high-temperature pressure characteristics of a wireless passive ceramic pressure sensor demonstrated at up to a temperature o... In this paper, a novel antenna is proposed for high-temperature testing, which can make the high-temperature pressure characteristics of a wireless passive ceramic pressure sensor demonstrated at up to a temperature of 600℃. The design parameters of the antenna are similar to those of the sensor, which will increase the coupling strength between the sensor and testing antenna. The antenna is fabricated in thick film integrated technology, and the properties of the alumina ceramic and silver ensure the feasibility of the antenna in high-temperature environments. The sensor, coupled with the ceramic antenna, is investigated using a high-temperature pressure testing platform. The experimental measurement results show that the pressure signal in a harsh environment can be detected by the frequency diversity of the sensor. 展开更多
关键词 ceramic antenna contactless pressure measurement high-temperature application wireless passive pressure sensor
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A Compact System of Capacitively Coupled Contactless Conductivity Detection Based on the Square Wave Excitation Signal for Capillary Electrophoresis 被引量:1
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作者 Shui Feng ZHANG Li Shi WANG Zhi DANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第9期1229-1232,共4页
This paper reported a compact system of capacitively coupled contactless conductivity detection (C4D) based on the square wave excitation voltage for capillary electrophoresis, and it exhibited excellent sensitivity... This paper reported a compact system of capacitively coupled contactless conductivity detection (C4D) based on the square wave excitation voltage for capillary electrophoresis, and it exhibited excellent sensitivity at the optimal frequency of 198 kHz. The feasibility and sensitivity of this detector was demonstrated by simultaneous detection of thirteen ions including alkali, alkaline earth and heavy metal ions. And the detection limits (S/N 3) were in the range of 0.2-1μmol/L for Mn^2+, K^+, Na^+, Mg^2+, Ca^2+, Li^+, Ba^2+, and 7-25 μmol/L for Ni^2+, Cu^2+, Cd^2+, Pb^2+, Co^2+, Zn^2+. 展开更多
关键词 Capillary electrophoresis square wave excitation signal contactless conductivitydetector metal ions.
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Sensitive Determination of Metal Ions in Drinking Water by Capillary Electrophoresis Coupled with Contactless Conductivity Detection Using 18-Crown-6 Ether and Hexadecyltrimethylammonium Bromide as Complexing Reagents 被引量:1
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作者 Wujuan Chen Fan Gao +5 位作者 Yi Zhang Yan Zhang Yi Li Yating Zhang Qingjiang Wang Pingang He 《American Journal of Analytical Chemistry》 2016年第11期737-747,共12页
A simple, economical, and sensitive capillary electrophoresis (CE) method integrated with capacitively coupled contactless conductivity detection was developed for the determination of metal ions such as K<sup>+... A simple, economical, and sensitive capillary electrophoresis (CE) method integrated with capacitively coupled contactless conductivity detection was developed for the determination of metal ions such as K<sup>+</sup>, Na<sup>+</sup>, Mg<sup>2+</sup>, Sr<sup>2+</sup>, Ca<sup>2+</sup> in drinking water. 18-Crown-6 ether and Hexadecyltrimethylammonium Bromide (CTAB) were employed as complexing reagents. The effects of electrolyte additives, citric acid buffer solution, and other separation conditions of CE were comprehensively investigated and carefully optimized. The best results were obtained in a running buffer solution composed of citric acid (12 mM), 18-crown-6 ether (0.2 mM), and CTAB (0.015 mM) at pH 3.5. Under these conditions, a complete separation of five metal ions was successfully achieved in less than 12 min. The limits of detection for the optimal procedure were determined to be in the range of 0.02 - 0.2 mg·L<sup>-1</sup>. The repeatability with respect to migration times and peak areas, expressed as relative standard deviations, was better than 2.3% and 5.1%, respectively. Evaluation of the efficiency of the methodology indicated that it was reliable for the determination of metal ions in six different brands of drinking water samples. 展开更多
关键词 Capillary Electrophoresis contactless Conductivity Detection Metal Ions FOOD Drinking Water
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Simultaneous laser-induced fluorescence and contactless-conductivity detection for microfluidic chip 被引量:1
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作者 Feng Shen Meng Yang +1 位作者 Yong Yu Qi Kang 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第11期1333-1336,共4页
A combined detection system involving simultaneous LIF and contacfless-conductometric measurements at the same place of the microfluidic chip was described. The LIF measurement was designed according to the confocal p... A combined detection system involving simultaneous LIF and contacfless-conductometric measurements at the same place of the microfluidic chip was described. The LIF measurement was designed according to the confocal principle and a moveable contactless-conduetivity detector was used in C^4D. Both measurements were mutually independent and advantageous in analyses of mixtures. Various experimental parameters affecting the response were examined and optimized. The performances were demonstrated by simultaneous detection of Rhodamine B. And the results showed that the combined detection system could be used sensitively and reliably. 展开更多
关键词 Microfluidic chip Laser-induced fluorescence (LIF) Capacitively coupled contactless-conductivity detection (C^4D)
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Contactless Raman Spectroscopy-Based Monitoring of Physical States of Silyl-Modified Polymers during Cross-Linking
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作者 Boris Colin Olivier Lavastre +4 位作者 Stéphane Fouquay Guillaume Michaud Frédéric Simon Olivier Laferte Jean-Michel Brusson 《Green and Sustainable Chemistry》 2016年第4期151-166,共17页
Cross-linking of silyl-modified polymers occurs at the alkoxysilane groups attached to the ends of polymer chains by hydrolysis and polycondensation mechanisms in the presence of moisture. During these reactions, thre... Cross-linking of silyl-modified polymers occurs at the alkoxysilane groups attached to the ends of polymer chains by hydrolysis and polycondensation mechanisms in the presence of moisture. During these reactions, three different physical states can be identified (viscous, skin effect and cross-linked state). Knowledge of the evolution of these states at each reaction time is essential to determine the open time for the adhe-sive industry and is generally obtained by a manual method. Automation of this moni-toring could avoid operator error and could be used for very long cross linking reac-tions or to screen a large number of catalysts. Thus, a contactless micro process tech-nology was developed to correlate these physical states with an optical technology, Raman spectroscopy, by monitoring the decrease in intensity of the Si-OCH<sub>3</sub> groups during chemical reactions. This online characterization method can also be used to compare the efficiencies of several catalysts for the cross-linking of silyl-modified polymers, using a minimum amount of chemical materials. 展开更多
关键词 Silyl Modified Polymers Physical States Micro contactless Monitoring Raman Spectroscopy Cross-Linking
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Transverse distribution law of airflow excitation force for SI-FLAT contactless shapometer
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作者 Yang Guanghui Zhang Jie Li Hongbo 《Computer Aided Drafting,Design and Manufacturing》 2016年第4期41-47,共7页
Aiming at the shape problems in production, the finite element model was built with the Fluent software to analyze the transverse distribution laws of airflow excitation force under different factors which affected th... Aiming at the shape problems in production, the finite element model was built with the Fluent software to analyze the transverse distribution laws of airflow excitation force under different factors which affected the detection precision. For analyzing the shape errors caused by the non-uniform transverse distribution of airflow excitation force, the finite element model of strip is built with the ANSYS12.0 software. It is found in the study results that the airflow excitation forces display the same distribution laws under different rolling conditions, i.e. have an obvious attenuation at the edge of strip~ which causes large shape measurement errors. For reducing shape errors, the compensation project is put forward, and it gives a good foundation for improving the detection precision. 展开更多
关键词 contactless measurement FLATNESS AMPLITUDE SI-FLAT shapometer airflow excitation force
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Analysis and Control of S/SP Compensation Contactless Resonant Converters 被引量:19
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作者 HOU Jia CHEN Qianhong YAN Kaiqin LI Mingshuo ZHANG Qiang RUAN Xinbo 《中国电机工程学报》 EI CSCD 北大核心 2013年第33期I0001-I0020,共20页
非接触谐振变换器的补偿方式直接影响到系统的增益特性和控制特性,是非接触能量传输技术的研究重点之一。考虑到非接触应用场合中的变参数特性,论文提出了一种可适应负载及变压器参数变化的新型的串/串并(series/seriesparallel,S... 非接触谐振变换器的补偿方式直接影响到系统的增益特性和控制特性,是非接触能量传输技术的研究重点之一。考虑到非接触应用场合中的变参数特性,论文提出了一种可适应负载及变压器参数变化的新型的串/串并(series/seriesparallel,S/SP)补偿拓扑。该补偿拓扑具有增益交点处输入相角为零,且增益交点值固定不随变压器耦合系数而改变的优点。论文对该新型补偿拓扑进行了特性分析;并针对其增益交点处输入相角为零以及增益交点处增益曲线相对平坦的优点,提出锁相环(phaselockloop,PLL)控制和恒频控制2种控制策略。采用所提出的补偿方式,设计了一台PLL控制60W的谐振变换器和一台1.5kW恒频控制的原理样机。实验结果与理论分析一致,验证了所提出的新型补偿方式的优点。1.5kW的样机在10cm气隙满载条件下效率达到95.2%。 展开更多
关键词 谐振变换器 非接触式 控制 补偿 SP 电力传输 动力传输 传递方式
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Contactless Magnetoresistance in Large Area Epitaxial Graphene Grown on SiC Substrates 被引量:1
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作者 Tymoteusz Ciuk Jerzy Krupka +5 位作者 Cezariusz Jastrzebski Jaroslaw Judek Wlodek Strupinski Serkan Butun Ekmel Ozbay Mariusz Zdrojek 《材料科学与工程(中英文A版)》 2012年第7期489-493,共5页
关键词 非接触式 SIC 石墨 衬底 面积 化学气相沉积方法 磁电阻效应 生长
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Contactless integrated photonic probes:fundamentals,characteristics,and applications
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作者 Guangze Wu Yuanjian Wan +4 位作者 Zhao Wang Xiaolong Hu Jinwei Zeng Yu Zhang Jian Wang 《Frontiers of Optoelectronics》 EI CSCD 2024年第3期69-82,共14页
On-chip optical power monitors are indispensable for functional implementation and stabilization of large-scale and complex photonic integrated circuits(PICs).Traditional on-chip optical monitoring is implemented by t... On-chip optical power monitors are indispensable for functional implementation and stabilization of large-scale and complex photonic integrated circuits(PICs).Traditional on-chip optical monitoring is implemented by tapping a small portion of optical power from the waveguide,which leads to signifcant loss.Due to its advantages like non-invasive nature,miniaturization,and complementary metal-oxide-semiconductor(CMOS)process compatibility,a transparent monitor named the contactless integrated photonic probe(CLIPP),has been attracting great attention in recent years.The CLIPP indirectly monitors the optical power in the waveguide by detecting the conductance variation of the local optical waveguide caused by the surface state absorption(SSA)efect.In this review,we frst introduce the fundamentals of the CLIPP including the concept,the equivalent electric model and the impedance read-out method,and then summarize some characteristics of the CLIPP.Finally,the functional applications of the CLIPP on the identifcation and feedback control of optical signal are discussed,followed by a brief outlook on the prospects of the CLIPP. 展开更多
关键词 contactless integrated photonic probes Photonic integrated circuits Silicon photonics Optical monitoring Feedback control
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Highly sensitive humidity sensors based on hexagonal boron nitride nanosheets for contactless sensing 被引量:1
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作者 Hang Liu Jinxu Qin +7 位作者 Xigui Yang Chaofan Lv Wentao Huang Fukui Li Chuang Zhang Yanran Wu Lin Dong Chongxin Shan 《Nano Research》 SCIE EI CSCD 2023年第7期10279-10286,共8页
Humidity sensors with high sensitivity,rapid response,and facile fabrication process for contactless sensing applications have received considerable attention in recent years.Herein,humidity sensors based on hexagonal... Humidity sensors with high sensitivity,rapid response,and facile fabrication process for contactless sensing applications have received considerable attention in recent years.Herein,humidity sensors based on hexagonal boron nitride(h-BN)nanosheets that are synthesized by a facile ultrasonic process have been fabricated,which display an ultrahigh sensitivity of 28,384%at 85%relative humidity(RH),rapid response/recovery time(3.0/5.5 s),and long-term stability in a wide humidity detection range(11%-85%RH),superior to most of the reported humidity sensors.The high sensitivity can be ascribed to the massive hydrophilic functional groups absorbed on the h-BN nanosheet surface.Benefiting from the high humidity sensing performances,contactless Morse code messaging and human writing and speech recognition have been demonstrated.This work demonstrates the great potential of the high-performance h-BN nanosheet-based humidity sensors for future contactless sensing devices. 展开更多
关键词 boron nitride humidity sensors contactless detection speech recognition
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Unified Analysis and Output Estimation for a Strong Coupling Contactless Slipring System
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作者 Guangming He Qianhong Chen +1 位作者 Xiaoyong Ren Zhiliang Zhang 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2023年第6期2263-2271,共9页
A contactless slipring (CS) system utilizing inductive-power-transfer (IPT) technology is a good candidate for traditional mechanical slipring assemblies. However, suffering from the high harmonic currents in strong c... A contactless slipring (CS) system utilizing inductive-power-transfer (IPT) technology is a good candidate for traditional mechanical slipring assemblies. However, suffering from the high harmonic currents in strong coupling CS systems, the output power will deviate from the theoretical values estimated by the fundamental harmonic approximation (FHA) and its extension method, i.e., E-FHA, in which the power is transferred by both the fundamental current and the high order harmonic currents. In order to achieve high precise output estimation, a unified analysis is proposed in this paper. First, “Fundamental-harmonic Double Resonance Phenomenon” is revealed via impedance analysis, to address the nature of the high harmonic currents in strong coupling systems. Then, a unified output current expression owning high precision is derived, and followed by a unified fundamental load impedance. Discussions show that both the output and the fundamental load impedance of FHA, and E-FHA are the special cases of the unified expressions proposed. FHA and E-FHA are precise enough for the loose coupling system, whereas the proposed method is indispensable for the strong coupling system with k>0.4 . Finally, simulations and experimental measurements of a 1.6kW CS system, as well as the comparative studies related to FHA, E-FHA, and the proposed method, are presented, indicating that the proposed method is effective for high precise output estimation. 展开更多
关键词 contactless slipring(CS) precise output estimation unified analysis
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用于土壤中氮钾含量快速测定的非接触电导微流控芯片 被引量:1
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作者 洪炎 王乐 +5 位作者 王儒敬 苏静明 李浩 张家宝 郭红燕 陈翔宇 《智慧农业(中英文)》 CSCD 2024年第1期18-27,共10页
[目的/意义]土壤中氮、钾元素在作物生长和农业生产过程中具有关键作用。快速定量检测土壤中氮、钾含量对指导精确施肥具有重要意义。因此,建立一种快速可靠的土壤氮、钾含量检测方法十分必要。[方法]本研究建立一种基于聚二甲基硅氧烷(... [目的/意义]土壤中氮、钾元素在作物生长和农业生产过程中具有关键作用。快速定量检测土壤中氮、钾含量对指导精确施肥具有重要意义。因此,建立一种快速可靠的土壤氮、钾含量检测方法十分必要。[方法]本研究建立一种基于聚二甲基硅氧烷(Polydimethylsiloxane,PDMS)微流控芯片电泳和电容耦合非接触电导检测(Capacitively Coupled Contactless Conductivity Detection,C4D)方法,快速定量检测土壤中氮、钾养分离子。通过微流控电泳芯片实现对土壤中多种离子快速分离,利用C4D进行电导率变化的精准测量。基于检测器工作频率输出响应特性,激励电压响应特性和电泳电压,确定最佳分离和检测性能。[结果和讨论]该方法对钾离子(K+)、铵根离子(NH4+)和硝酸根离子(NO_(3)^(-))标准溶液的检测限(S/N=3)分别为0.5、0.1和0.4 mg/L。K^(+)、NH_(4)^(+)和NO_(3)^(-)在0.5~40.0 mg/L范围内具有良好的线性关系,线性相关系数(R2)分别为0.994、0.997和0.990,表明该方法可以对土壤中氮、钾养分离子进行定量分析。同时,采用峰高、峰面积和出峰时间作为评价指标进行可重复性实验,其相对标准偏差(Relative Standard Deviation,RSD)均小于4.4%,说明该方法具有良好的重复性。此外,对土壤样品进行测试,K^(+)和NH_(4)^(+)可实现完全分离以及同步检测,其检测效率明显提高。通过标准加入法进行回收率实验,回收率保持在81.74%~127.76%。[结论]本研究为土壤氮钾养分离子的快速检测提供了一种简便、高效的方法。 展开更多
关键词 非接触电导检测 微流控芯片 土壤养分 聚二甲基硅氧烷
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基于STM32的频率和功率可调非接触供电超声电源设计 被引量:1
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作者 徐建新 董博博 +4 位作者 刘礼平 林彬 房丰洲 朱学明 杨兰旗 《声学技术》 CSCD 北大核心 2024年第2期224-233,共10页
为解决接触式供电中漏电、磨损、电能传输不良以及超声电源在加工中谐振频率漂移、跟踪速度慢、输出功率不稳定等问题,文章以STM32单片机作为主控系统,设计了一种频率和功率可调的非接触供电超声电源。根据采样反馈电路采集的电压电流... 为解决接触式供电中漏电、磨损、电能传输不良以及超声电源在加工中谐振频率漂移、跟踪速度慢、输出功率不稳定等问题,文章以STM32单片机作为主控系统,设计了一种频率和功率可调的非接触供电超声电源。根据采样反馈电路采集的电压电流相位差和有效值信号,采用锁相环和模糊比例积分(Proportional Integral,PI)控制相结合的方法对频率进行跟踪,并用传统PI控制法控制输出功率。在Matlab软件中搭建电源仿真模型,利用附加电阻、附加电感和附加电容模拟加工过程中负载参数的突变,对有频率调节和功率控制子系统以及没有子系统的电源模型分别进行仿真。仿真结果表明,电源输出功率稳定在248 W。当负载参数发生改变时,电源的谐振频率发生漂移,经过频率自动跟踪子系统的调节后,电源在0.01 s后重新回到谐振状态。此控制算法实现了频率快速跟踪和功率控制。 展开更多
关键词 非接触供电超声波电源 负载参数 频率快速跟踪 功率控制
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非接触电导检测土壤养分离子的谱峰自动识别方法
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作者 唐超礼 李浩 +5 位作者 王儒敬 王乐 黄青 王大朋 张家宝 陈翔宇 《智慧农业(中英文)》 CSCD 2024年第1期36-45,共10页
[目的/意义]电容耦合非接触式电导检测(Capacitively Coupled Contactless Conductivity Detection,C4D)在农业土壤养分离子检测方面发挥着重要作用。对C4D信号中离子特征峰的有效识别,有利于后续对离子特征峰的定性和定量分析,为加强... [目的/意义]电容耦合非接触式电导检测(Capacitively Coupled Contactless Conductivity Detection,C4D)在农业土壤养分离子检测方面发挥着重要作用。对C4D信号中离子特征峰的有效识别,有利于后续对离子特征峰的定性和定量分析,为加强农业土壤养分管理提供依据。然而,C4D信号的特征峰检测仍然存在无法自动精准识别、人工操作复杂、效率低等缺点。[方法]提出一种基于连续小波变换结合粒子群优化(Particle Swarm Optimization,PSO)和最大类间方差法(Otsu)的谱峰自动识别算法,旨在实现准确、高效、自动化的C4D信号峰识别。采用C4D检测样品溶液,得到离子谱图信号,对谱图信号进行连续小波变换,得到小波变换系数矩阵。通过搜索小波系数变换系数矩阵极值,识别出脊线和谷线。将小波系数矩阵转换为灰度图像,结合PSO和Otsu寻找最佳阈值,进一步对灰度图像的背景和目标分割,再结合原始谱图中的脊谷线识别谱图中的特征峰。[结果与讨论]测试含有41、61和102个峰的数据集,以受试者工作特性(Receiver Operating Characteristic,ROC)曲线和度量值作为评估峰值检测算法性能的准则。与其他方法相比,基于连续小波变换结合粒子群优化的最大类间方差法分割图像(Continuous Wavelet Transform C.ombined with Particle Swarm Optimization of Otsu to Segment Image,CWTSPSO)的谱峰自动识别算法的ROC曲线均保持在0.9以上,度量值分别为0.976、0.915和0.969。CWTSPSO能够有效检测出更多弱峰和重叠峰,同时检测出更少的假峰,有利于提升C4D信号的谱峰识别率和精准性。[结论]本研究提出的CWTSPSO能为非接触式电导检测农业土壤养分离子信号分析提供有力支持。 展开更多
关键词 非接触式电导检测 连续小波变换 粒子群优化算法 最大类间方差法 谱峰识别
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基于Wi-Fi子载波互信息的人体呼吸感知系统
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作者 刘影 胡梦圆 钱志鸿 《通信学报》 EI CSCD 北大核心 2024年第2期240-253,共14页
不可预测环境变化使Wi-Fi信号存在较大的波动,很难对子载波中的静态分量和行为感知的动态分量进行量化,导致无法准确刻画出动态呼吸特征的波动形式。基于此,提出了一种基于子载波互信息的呼吸感知(SMIBP)系统。首先,提出了动态分量信息(... 不可预测环境变化使Wi-Fi信号存在较大的波动,很难对子载波中的静态分量和行为感知的动态分量进行量化,导致无法准确刻画出动态呼吸特征的波动形式。基于此,提出了一种基于子载波互信息的呼吸感知(SMIBP)系统。首先,提出了动态分量信息(DCI)的刻画形式,利用互信息理论提取子载波中代表呼吸的动态分量信息。然后,利用层次分析法组合各子载波以最大化呼吸信号的动态特征,得到重构的DCI感知基信号,最后联合小波变换和峰值检测法得到呼吸速率,揭示了代表人体呼吸动态分量的理论途径。仿真结果表明,所提系统能较好地刻画每个子载波中动态呼吸分量,且在不同场景下可显著提高Wi-Fi对于小尺度动作的感知精度与范围。 展开更多
关键词 动态分量信息 信道状态信息 无接触呼吸监测 层次分析法
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基于GaN/Ti_(3)C_(2)T_(x)的TMA传感器气敏性能及其应用研究
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作者 韩丹 洪宇涛 +5 位作者 刘志华 段奇 李栋辉 王雨 史杰旭 桑胜波 《电子学报》 EI CAS CSCD 北大核心 2024年第4期1389-1398,共10页
本文联合溶剂热法和氮化法合成氮化镓(GaN)/Ti_(3)C_(2)T_(x)新型复合材料,并研究了基于GaN/Ti_(3)C_(2)T_(x)新型复合材料的气体传感器对三甲胺(Trimethylamine,TMA)气体的传感特性.通过一系列表征手段分析了复合材料的形貌以及元素组... 本文联合溶剂热法和氮化法合成氮化镓(GaN)/Ti_(3)C_(2)T_(x)新型复合材料,并研究了基于GaN/Ti_(3)C_(2)T_(x)新型复合材料的气体传感器对三甲胺(Trimethylamine,TMA)气体的传感特性.通过一系列表征手段分析了复合材料的形貌以及元素组成特性,证实了GaN与Ti_(3)C_(2)T_(x)材料的成功复合.传感器对TMA气体的气敏特性结果表明,GaN/Ti_(3)C_(2)T_(x)传感器在室温下能够高效检测1~200 ppm的TMA气体,且与纯GaN传感器相比,对TMA的检测下限由10 ppm降低至1 ppm.此外,复合传感器气敏结果进一步证实了其良好的抗干扰特性以及长期稳定性.利用表面耗尽层模型解释了GaN/Ti_(3)C_(2)T_(x)复合传感器气敏机理,及其与纯GaN传感器相比气敏性能提升的原因.最后,本文开发了一种无接触式TMA气体检测装置,检测结果表明该装置有望实现对肝、肾病患者呼出气的高效实时检测,在肝、肾疾病的早期筛查方面具有较大的应用潜力. 展开更多
关键词 GaN/Ti_(3)C_(2)T_(x) 室温 三甲胺 气体传感器 无接触检测
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