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Obstacles to the Integrated Care of Children Aged 6 to 59 Months Suffering from Acute and Severe Malnutrition at the Chu-Me and HATC of N’Djamena/Chad
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作者 Madjiadoumbeye Romain Imar Djibrine Soudy 《Open Journal of Nursing》 2024年第4期127-138,共12页
Introduction: the problem of Severe Acute Malnutrition (SAM) and its consequences concern and challenge all social actors worldwide. The objective of the study was to identify the real obstacles that actors face in th... Introduction: the problem of Severe Acute Malnutrition (SAM) and its consequences concern and challenge all social actors worldwide. The objective of the study was to identify the real obstacles that actors face in the integrated management of children aged 6 - 59 months suffering from SAM at the University Hospital of Mother and Child (CHUME) and the Chad-China Friendship Hospital (HATC) of N’Djamena. Methodology: this is a cross-sectional descriptive and interpretative study conducted from January to October 2023 at the CHUME and HATC of N’Djamena. It is based on questionnaires and direct observation of two hundred and thirty-six (236) parents or guardians of malnourished children admitted to these health facilities. All 236 agreed to participate freely in this study. Results: it appears from this study that the obstacles to the integrated management of malnourished children were: poor care-care relationship (26.7%) permanent product breaks (22.9%), the direct costs of services ranged from 30,000 to 60,000 FCFA (41.53%), drugs used for the treatment of patients came from the street (66.10%), malaria and anemia occupy an important place (27.5%), 57.2% respondents had monthly income below 60,000 CFAF. Conclusion: the present study carried out has identified the real bottlenecks to the integrated management of children suffering from SAM in the therapeutic nutritional units of the city of N’Djamena. . 展开更多
关键词 integrated Management Child 6 - 59 Months SAM
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An advanced Ⅲ-Ⅴ-on-silicon photonic integration platform 被引量:1
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作者 Yingtao Hu Di Liang Raymond G.Beausoleil 《Opto-Electronic Advances》 SCIE 2021年第9期14-27,共14页
In many application scenarios,silicon(Si)photonics favors the integration of Ⅲ-Ⅴ gain material onto Si substrate to real-ize the on-chip light source.In addition to the current popular integration approaches of Ⅲ-... In many application scenarios,silicon(Si)photonics favors the integration of Ⅲ-Ⅴ gain material onto Si substrate to real-ize the on-chip light source.In addition to the current popular integration approaches of Ⅲ-Ⅴ-on-Si wafer bonding or dir-ect heteroepitaxial growth,a newly emerged promising solution of epitaxial regrowth on bonded substrate has attracted a lot of interests.High-quality Ⅲ-Ⅴ material realization and successful laser demonstrations show its great potential to be a promising integration platform for low-cost,high-integration density and highly scalable active-passive photonic integra-tion on Si.This paper reviews recent research work on this regrowth on bonded template platform including template de-velopments,regrown material characterizations and laser demonstrations.The potential advantages,opportunities and challenges of this approach are discussed. 展开更多
关键词 Si photonics --on-Si laser photonic integration epitaxy regrowth
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Integration and verification case of IP-core based system on chip design 被引量:3
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作者 胡越黎 周谌 《Journal of Shanghai University(English Edition)》 CAS 2010年第5期349-353,共5页
In this paper, the design and verification process of an automobile-engine-fan control system on chip (SoC) are introduced. The SoC system, SHU-MV08, reuses four new intellectual property (IP) cores and the design... In this paper, the design and verification process of an automobile-engine-fan control system on chip (SoC) are introduced. The SoC system, SHU-MV08, reuses four new intellectual property (IP) cores and the design flow is accomplished with 0.35 btm chartered CMOS technology. Some special functions of IP cores, the detailed integration scheme of four IP cores, and the verification method of the entire SoC are presented. To settle the verification problems brought by analog IP cores, NanoSim based chip-level mixed-signal verification method is introduced. The verification time is greatly reduced and the first tape-out achieves success which proves the validity of our design. 展开更多
关键词 system on chip (SoC) intellectual property (IP)-core integration VERIFICATION pulse width modulation (PWM)- analog digital converter (ADC) linkage running
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A new integration algorithm for finite deformation of thermo-elasto-viscoplastic single crystals
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作者 Dan Zhao Yi-Guo Zhu +1 位作者 Ping Hu Wan-Xi Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第5期709-717,共9页
An algorithm for integrating the constitutive equations in thermal framework is presented, in which the plastic deformation gradient is chosen as the integration variable. Compared with the classic algorithm, a key fe... An algorithm for integrating the constitutive equations in thermal framework is presented, in which the plastic deformation gradient is chosen as the integration variable. Compared with the classic algorithm, a key feature of this new approach is that it can describe the finite deformation of crystals under thermal conditions. The obtained plastic deformation gradient contains not only plastic defor- mation but also thermal effects. The governing equation for the plastic deformation gradient is obtained based on ther- mal multiplicative decomposition of the total deformation gradient. An implicit method is used to integrate this evo- lution equation to ensure stability. Single crystal 1 100 aluminum is investigated to demonstrate practical applications of the model. The effects of anisotropic properties, time step, strain rate and temperature are calculated using this integration model. 展开更多
关键词 integration algorithm - Thermal effect Anisotropic elasticity Single crystal Finite deformation
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A 330-500 GHz Zero-Biased Broadband Tripler Based on Terahertz Monolithic Integrated Circuits 被引量:2
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作者 任田昊 张勇 +4 位作者 延波 徐锐敏 杨成樾 周静涛 金智 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第2期31-34,共4页
A 330-500 GHz zero-biased broadband monolithic integrated tripler is reported. The measured results show that the maximum efficiency and the maximum output power are 2% and 194μW at 348 GHz. The saturation characteri... A 330-500 GHz zero-biased broadband monolithic integrated tripler is reported. The measured results show that the maximum efficiency and the maximum output power are 2% and 194μW at 348 GHz. The saturation characteristic test shows that the output i dB compression point is about -8.5 dBm at 334 GHz and the maximum efficiency is obtained at the point, which is slightly below the 1 dB compression point. Compared with the conventional hybrid integrated circuit, a major advantage of the monolithic integrated circuit is the significant improvement of reliability and consistency. In this work, a terahertz monolithic frequency multiplier at this band is designed and fabricated. 展开更多
关键词 InP InGaAs A 330-500 GHz Zero-Biased Broadband Tripler Based on Terahertz Monolithic integrated Circuits dBm SBD
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Application of vertically integrated sampling approach to study of new production via ^(234)Th -^(238)U disequilibria 被引量:1
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作者 Chen Feizhou1 Huang Yipu2 Chen Min2 (1. College of Fishery Science, Shanghai Fisheries University, Shanghai 200090, China 2. Department of Oceanography, Xiamen University, Xiamen 361005, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2000年第2期37-44,共8页
The spatial and temporal distributions of new production vary largely in different sea areas. To understand the level of new production in the sea area studied better, an estimate of new production must be obtained in... The spatial and temporal distributions of new production vary largely in different sea areas. To understand the level of new production in the sea area studied better, an estimate of new production must be obtained in large spatial and temporal scales. The ~234Th/ ~238U disequilibrium is an effective method for the study of new production. Two sampling strategies, vertically integrated sampling ap proach based on trapezoidal integration principle and discrete layer sampling approach, were compared in the studies of the xiamen Bay and the northern South China Sea. The scavenging fluxes and removal fluxes of ~234Th and the residence times for dissolved and particulate ~234Th were calculated. The coinci dent results from two Sampling approach suggest that vertically integrated sampling approach is not only effective and reliable, but also significantly reduces the number and volume of samples. It allows us to study new production by ba ^(234)Th - ^(238)U disequilibria in large spatial scale. 展开更多
关键词 New production vertically integrated Sampling approach ^(234)Th - ^(238)U disequilibria Xia men Bay northern South China Sea
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A Class of Singular Integral Equation of Convolution Type with CSC(τ- θ) Kernel
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作者 LI Ping-run 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第4期620-626,共7页
In this paper, we propose and discuss a class of singular integral equation of convolution type with csc(τ- θ) kernel in class L2[-π, π]. Using discrete Fourier transform and the lemma, this kind of equations is t... In this paper, we propose and discuss a class of singular integral equation of convolution type with csc(τ- θ) kernel in class L2[-π, π]. Using discrete Fourier transform and the lemma, this kind of equations is transformed to discrete system of equations, and then we obtain the solvable conditions and the explicit solutions in class L2[-π, π]. 展开更多
关键词 singular integral equation convolution type csc(τ-θ) kernel
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Pulsed Eddy Current Non-destructive Testing and Evaluation:A Review 被引量:29
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作者 Ali Sophian Guiyun Tian Mengbao Fan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期500-514,共15页
Pulsed eddy current (PEC) non-destructive test- ing and evaluation (NDT&E) has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed th... Pulsed eddy current (PEC) non-destructive test- ing and evaluation (NDT&E) has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed through the reports reviewed in this paper. Thanks to its richness of spectral components, various applications of this technique have been proposed and reported in the lit- erature covering both structural integrity inspection and material characterization in various industrial sectors. To support its development and for better understanding of the phenomena around the transient induced eddy currents, attempts for its modelling both analytically and numeri- cally have been made by researchers around the world. This review is an attempt to capture the state-of-the-art development and applications of PEC, especially in the last 15 years and it is not intended to be exhaustive. Future challenges and opportunities for PEC NDT&E are also presented. 展开更多
关键词 Non-destructive testing - Pulsed eddy currentsMaterial characterization Structural integrity Non-destructive evaluation
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Latest advances in high-performance light sources and optical amplifiers on silicon 被引量:5
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作者 Songtao Liu Akhilesh Khope 《Journal of Semiconductors》 EI CAS CSCD 2021年第4期81-89,共9页
Efficient light generation and amplification has long been missing on the silicon platform due to its well-known indirect bandgap nature.Driven by the size,weight,power and cost(SWaP-C)requirements,the desire to fully... Efficient light generation and amplification has long been missing on the silicon platform due to its well-known indirect bandgap nature.Driven by the size,weight,power and cost(SWaP-C)requirements,the desire to fully realize integrated silicon electronic and photonic integrated circuits has greatly pushed the effort of realizing high performance on-chip lasers and amplifiers moving forward.Several approaches have been proposed and demonstrated to address this issue.In this paper,a brief overview of recent progress of the high-performance lasers and amplifiers on Si based on different technology is presented.Representative device demonstrations,including ultra-narrow linewidthⅢ-Ⅴ/Si lasers,fully integratedⅢ-Ⅴ/Si/Si3N4 lasers,high-channel count mode locked quantum dot(QD)lasers,and high gain QD amplifiers will be covered. 展开更多
关键词 -Ⅴ/Si photonic integrated circuits semiconductor lasers semiconductor amplifier quantum dots
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磁性碳质材料催化糖类制备5-羟甲基糠醛和5-乙氧基甲基糠醛的研究 被引量:2
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作者 姚远 王海军 《应用化工》 CAS CSCD 北大核心 2016年第7期1258-1261,1266,共5页
制备了一种磺酸化的磁性碳质固体酸催化剂PCM-SO_3H,用于催化糖类制备液态生物燃料5-乙氧基甲基糠醛(EMF),考察了二甲亚砜在溶剂中的含量对糖类转化和产物分布的影响。结果表明,该催化剂不仅能催化5-羟甲基糠醛(HMF)的醚化,EMF产率高达8... 制备了一种磺酸化的磁性碳质固体酸催化剂PCM-SO_3H,用于催化糖类制备液态生物燃料5-乙氧基甲基糠醛(EMF),考察了二甲亚砜在溶剂中的含量对糖类转化和产物分布的影响。结果表明,该催化剂不仅能催化5-羟甲基糠醛(HMF)的醚化,EMF产率高达85.6%,也能在乙醇-二甲亚砜双溶剂体系下一锅法催化果糖制备EMF,反应温度100℃,反应时间10 h,催化剂加入量45 mg,溶剂(DMSO 1.5 m L和乙醇3.5 m L)时,EMF的收率达61.8%。反应结束后,该催化剂可以在外部磁场条件下从反应混合物中重新获得,且重复使用多次依然保持高的活性。 展开更多
关键词 果糖 5-羟甲基糠醛(HMF) 5-乙氧基甲基糠醛(emf) 二甲亚砜
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BOUNDEDNESS OF HIGHER ORDER COMMUTATORS OF GENERALIZED FRACTIONAL INTEGRAL OPERATORS ON HARDY SPACES 被引量:2
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作者 Chunlei He Lisheng Shu 《Analysis in Theory and Applications》 2005年第3期249-257,共9页
关键词 (θ - N)-type fractional integral operator COMMUTATOR BMO space Hardy space Herz-type Hardy space ATOM
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Integrated Knitwear Production for Hong Kong and the Interior of China
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作者 区健勋 李慧娟 《Journal of China Textile University(English Edition)》 EI CAS 2000年第3期94-99,共6页
Hong Kong knitwear manufacturers were among the pioneers to invest in the Pearl River Delta region of Guang-dong,China.Owing to limitations on technological levelat the time of the initial investments,the content of p... Hong Kong knitwear manufacturers were among the pioneers to invest in the Pearl River Delta region of Guang-dong,China.Owing to limitations on technological levelat the time of the initial investments,the content of pro-duction-sharing for the Inland in China were basically of simple technology and labour intensive in nature.Through venturing hardships,the investment has been able to boost the economy of Guangdong and foster close trade relationship,especially in outward processing trade,By now,the co-operative production 展开更多
关键词 ECONOMIC integration co - OPERATIVE PRODUCTION KNITWEAR supply pipeline outward processing.
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Maxim Integrated推出业内采样速率最快的20位SARADC
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《测控技术》 CSCD 北大核心 2014年第7期159-159,共1页
Maxim公司推出20位、1.6MS/s逐次逼近寄存器(SAR)模/数转换器(ADC)MAX11905,使设计人员能够以最低功耗实现业内最高分辨率和最快采样速率。工程师在高精度数据转换设计中通常会选取∑-△ADC。然而,为实现高精度和宽动态范围,... Maxim公司推出20位、1.6MS/s逐次逼近寄存器(SAR)模/数转换器(ADC)MAX11905,使设计人员能够以最低功耗实现业内最高分辨率和最快采样速率。工程师在高精度数据转换设计中通常会选取∑-△ADC。然而,为实现高精度和宽动态范围,此类ADC的功耗通常在100mw以上。而MAX11905SARADC的功耗仅为9mW,降幅达91%。除有效降低功耗外,器件还具有超高(20位)精度和最快的采样速率(1.6MS/s)。MAX11905还集成内部基准缓冲器,有效降低成本、加快产品上市,与分立竞争方案相比可节省高达50%的空间。MAX11905功能丰富,是过程控制、自动检测设备、医疗仪表和电池供电设备等多种应用的理想选择。 展开更多
关键词 Maxim公司 integrATED 采样速率 -△ADC 模/数转换器 自动检测设备 电池供电设备 最高分辨率
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The Role of <sup>18</sup>F-FDG PET/CT in Staging Breast Carcinoma in Hanoi Oncology Hospital, Vietnam
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作者 Cuong Duy Dang Thang Van Nguyen +1 位作者 Tuynh Van Chu Huy Quang Pham 《Journal of Biosciences and Medicines》 2022年第1期190-201,共12页
<strong>Purpose:</strong> This study aimed to evaluate the role of <sup>18</sup>F-FDG PET/CT scans in staging breast carcinoma. <strong>Materials and Methods:</strong> A descriptive... <strong>Purpose:</strong> This study aimed to evaluate the role of <sup>18</sup>F-FDG PET/CT scans in staging breast carcinoma. <strong>Materials and Methods:</strong> A descriptive study on 46 patients who were diagnosed with breast carcinoma in Hanoi Oncology Hospital, Vietnam from June 2019 to June 2021. Those patients underwent <sup>18</sup>F-FDG PET/CT scans for pre-treatment staging. <strong>Results:</strong> There was a positive correlation between the size of primary tumors and their SUV (p < 0.0001, r = 0.759). The mean SUV was reported to be 2.5 for tumors under 2 cm, 5.89 for tumors from 2 - 5 cm, 13.6 for tumors above 5 cm, and 8.23 for skin invasive lesions. In terms of regional lymph node metastasis detection, the sensitivity and specificity of <sup>18</sup>F-FDG PET/CT were 75% and 100%, respectively. The rate of distant metastasis detection was 15.2% (7/46 patients). Metastatic lesions were found in bone, lungs, liver, and lymph nodes. There was a significant difference in SUV among organs (p < 0.001), with the highest SUV found in bone metastasis. The rates of stage I, II, III and IV diagnosed after PET/CT are 8.7%;45.7%;30.4% and 15.2% respectively, compared to 10.9%;54.3%;32.6%;2.2% before taking <sup>18</sup>F-FDG PET/CT. After PET/CT, 17.4% patients (8/46) had their treatment plan changed. <strong>Conclusions: </strong><sup>18</sup>F-FDG PET/CT plays an important role in staging breast carcinoma. Determining accurately the breast carcinoma stage by <sup>18</sup>F-FDG PET/CT could help alter treatment strategy to best suit with patients, and avoid unnecessary surgery. 展开更多
关键词 18F-FDG PET/CT (Positron Emission Tomography with 2-Deoxy-2-[Fluorine-18]Fluoro-D-Glucose integrated with Computed Tomography) Breast Carcinoma STAGING SUV (Standardized Uptake Value)
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永磁直线同步电机无位置传感器控制研究
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作者 黄楠 卢琴芬 《微特电机》 2023年第8期36-40,46,共6页
为了实现表贴式永磁直线同步电机(SPMLSM)的无位置传感器运行,采用开环转闭环的控制方法。PMLSM在起动定位后开环起动,基于反电动势积分法估算动子角度;逐步降低初级电压幅值减小电流,观测开环电流矢量与动子估算角度的夹角,在合适夹角... 为了实现表贴式永磁直线同步电机(SPMLSM)的无位置传感器运行,采用开环转闭环的控制方法。PMLSM在起动定位后开环起动,基于反电动势积分法估算动子角度;逐步降低初级电压幅值减小电流,观测开环电流矢量与动子估算角度的夹角,在合适夹角下平稳切换到闭环状态,有效降低了电流与速度的超调,重点解决了低速域下观测磁链的漂移和平稳切换问题。基于SPMLSM实验平台验证了控制算法的有效性,表明当运行速度为3 Hz时动子位置估算结果的均方根误差为0.065 rad,在该误差内可平滑切换,验证了反电动势积分法能够在低速域下实现SPMLSM的无位置传感器控制。 展开更多
关键词 永磁直线同步电机 无位置传感器控制 反电动势积分法 磁链中值法
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大定源瞬变电磁法矩形发射回线激发的电磁场 被引量:21
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作者 李建慧 刘树才 +2 位作者 李富 赵贤任 刘仰光 《物探化探计算技术》 CAS CSCD 2008年第2期154-157,共4页
首先从垂直磁偶极子产生的电磁场表达式出发,推导出了矩形发射回线产生的电磁场表达式;然后通过Guptasarma积分和Hankel积分将这些表达式转换为时间域电磁场,求出感应电动势;最后通过模型计算来难验证其正确性。通过数值模拟发现,在层... 首先从垂直磁偶极子产生的电磁场表达式出发,推导出了矩形发射回线产生的电磁场表达式;然后通过Guptasarma积分和Hankel积分将这些表达式转换为时间域电磁场,求出感应电动势;最后通过模型计算来难验证其正确性。通过数值模拟发现,在层状介质模型情况下,矩形发射回线中心区域电磁场的瞬变响应近乎均匀,地表低阻层对电磁场有很强的屏蔽作用。 展开更多
关键词 大定源瞬变电磁法 矩形回线 Guptasarma积分 感应电动势
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基于DEM数据的北天山地貌形态分析 被引量:35
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作者 赵洪壮 李有利 +1 位作者 杨景春 吕红华 《地理科学》 CSCD 北大核心 2009年第3期445-449,共5页
基于SRTM3-DEM数据,运用GIS空间分析技术,通过面积-高度积分、地形高程(平均高程、最大高程、最小高程)、地势起伏度及地形剖面线方法,对北天山的地貌特征进行了初步分析。结果表明,北天山山势险峻并且呈NW-SE走向,显示天山受南北向水... 基于SRTM3-DEM数据,运用GIS空间分析技术,通过面积-高度积分、地形高程(平均高程、最大高程、最小高程)、地势起伏度及地形剖面线方法,对北天山的地貌特征进行了初步分析。结果表明,北天山山势险峻并且呈NW-SE走向,显示天山受南北向水平挤压隆升作用。近S形的面积-高度曲线、偏高的面积高度积分值表明北天山地区处于构造活跃时期,地貌发育属壮年期的早期阶段。地形高程剖面线揭示了北天山存在3级夷平面地貌特征,地势起伏度变化幅度最大地区则是受陆内挤压构造应力影响地形抬升最强的地区。 展开更多
关键词 数字高程模型(DEM) 面积-高度积分(hypsometric integral) 夷平面 构造地貌 天山
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基于反电动势积分法的无位置传感器直流无刷电机试探性起动研究 被引量:7
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作者 王大方 刘智祺 +1 位作者 金毅 赵桂范 《电工技术学报》 EI CSCD 北大核心 2012年第12期178-184,共7页
无位置传感器直流无刷电机三段式起动的难点在于同样的起动参数难以适应不同起动转矩负载。为了提高对不同负载的起动成功率及平稳性,设计了采用反电动势积分法的无传感器直流无刷电机试探性起动方法。证明了反电动势积分换相法的积分... 无位置传感器直流无刷电机三段式起动的难点在于同样的起动参数难以适应不同起动转矩负载。为了提高对不同负载的起动成功率及平稳性,设计了采用反电动势积分法的无传感器直流无刷电机试探性起动方法。证明了反电动势积分换相法的积分阈值在不同工况下为定值,指出了反电动势积分法应用在起动阶段的独特优势。分析了转子磁动势与定子磁动势成不同角度时电机起动阶段非导通相的反电动势波形特征。作为判断转子磁动势指向区间的依据。设计了采用该方法的无传感器直流无刷电机控制器。实验结果证明该方法保证了起动成功率,提高了起动平稳性,起动阶段的转矩、电流响应快速而平稳。 展开更多
关键词 直流无刷电机 无位置传感器 反电动势积分 试探性起动
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永磁无刷直流电动机基于反电势的无传感器控制技术综述 被引量:19
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作者 沈建新 陈永校 《微特电机》 北大核心 2006年第7期36-40,共5页
无刷直流电动机的无位置传感器控制技术是业内近二十年来的一个重要研究方向。已经有多种技术见诸报道。文章对基于反电势的无传感器控制方法作一综合介绍和比较。
关键词 无刷直流电动机 无传感器控制 反电势 过零点 电压积分 锁相环
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基于反电势积分补偿法的无刷直流电动机控制 被引量:7
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作者 李声晋 马晖 +1 位作者 卢刚 李晓明 《微特电机》 北大核心 2008年第6期37-39,57,共4页
针对无位置传感器无刷直流电动机的控制要求,采用反电势积分法来获取转子位置信号,根据电机转速进行相位补偿,实现了电机的准确换相控制;采用升频升压法实现电机的起动和加速,最终切换为无位置传感器无刷工作状态。实验结果表明,系统起... 针对无位置传感器无刷直流电动机的控制要求,采用反电势积分法来获取转子位置信号,根据电机转速进行相位补偿,实现了电机的准确换相控制;采用升频升压法实现电机的起动和加速,最终切换为无位置传感器无刷工作状态。实验结果表明,系统起动正常,能够在无位置传感器状况下正常工作,已经得到了成功的应用。 展开更多
关键词 反电势积分 相位补偿 升频升压 无刷直流电动机 无位置传感器
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