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A Six DOF Compliant Force/Torque Sensor 被引量:1
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作者 王全玉 赵杰 +1 位作者 冉祥来 蔡鹤皋 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第3期18-21,共4页
A compliant F/T sensor which combines passive compliance and active sensing is proposed in thes paper to provide flexible utility. The paper describes the sensor’s mechanical design, measuring theory and kinematic eq... A compliant F/T sensor which combines passive compliance and active sensing is proposed in thes paper to provide flexible utility. The paper describes the sensor’s mechanical design, measuring theory and kinematic equations which are set up in the RPY (roll-pitch-yaw) mode.The sensor’S poSe vector can be acquired if the position signals from the PSDS are known, and vice versa. The formula between force vector and pose vector is built so that the force/ torque can be acquired after the stiffness matrix is calibrated. 展开更多
关键词 PASSIVE COMPLIANCE Compliant f/t sensor KINEMAtICS StIffNESS MAtRIX
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基于光纤Fabry-Perot滤波的光纤激光温度传感系统
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作者 杨帆 李邵德 +1 位作者 刘灏冲 何巍 《光学技术》 CAS CSCD 北大核心 2024年第4期453-458,共6页
提出并设计了一种基于氢氟酸腐蚀技术制备光纤微腔的方法,并通过熔接4.5mm长的单模光纤构成全光纤(Fabry-Perot,F-P)多光束干涉滤波结构,其主干涉谱周期为20.7nm,次级干涉谱周期为1.4nm;在此基础上,以光纤F-P滤波器作为选频器件搭建了... 提出并设计了一种基于氢氟酸腐蚀技术制备光纤微腔的方法,并通过熔接4.5mm长的单模光纤构成全光纤(Fabry-Perot,F-P)多光束干涉滤波结构,其主干涉谱周期为20.7nm,次级干涉谱周期为1.4nm;在此基础上,以光纤F-P滤波器作为选频器件搭建了掺铒光纤激光系统,实现了中心波长1560.40nm,信噪比15.441dB,3dB线宽0.28nm的窄线宽激光输出。实验中通过温度加热平台分别对光纤F-P滤波器进行升温和降温实验,在360~430℃的温度实验范围内,升温过程中激光波长产生红移,传感系统的温度灵敏度为13.80pm/℃,线性拟合度为99.82%;降温过程中激光传感系统的温度灵敏度为13.36pm/℃,线性拟合度为99.44%。本研究为高精度高温传感提供了一种激光系统测量方法。 展开更多
关键词 光纤f-P滤波器 光纤激光器 氢氟酸 光纤温度传感
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基于多目标分析的F-T柴油机SOOT和NO_(X)排放物优化研究
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作者 孟源 闫飞 《中国农机化学报》 北大核心 2024年第11期119-124,共6页
为充分发挥F-T煤制油的优良理化特性,改善柴油机SOOT和NO_(X)之间的“Trade-off”关系,以一台四缸柴油机为研究对象,将SOOT和NO_(X)作为优化目标。通过台架试验获得柴油机燃用F-T煤制油时SOOT和NO_(X)随喷油参数变化的性能试验数据,采... 为充分发挥F-T煤制油的优良理化特性,改善柴油机SOOT和NO_(X)之间的“Trade-off”关系,以一台四缸柴油机为研究对象,将SOOT和NO_(X)作为优化目标。通过台架试验获得柴油机燃用F-T煤制油时SOOT和NO_(X)随喷油参数变化的性能试验数据,采用支持向量机SVM建立喷油参数与SOOT、NO_(X)间的预测模型,并将其作为带精英策略的非支配排序遗传算法的适应度评价模型,在样本空间内获得SOOT和NO_(X)的Pareto前沿。赋予SOOT和NO_(X)不同的权重,通过Topsis对Pareto前沿进行决策分析,与原机工况点相比,SOOT下降幅度为3.7%~7.1%,NO_(X)下降幅度为1.2%~2.6%。经试验验证,SOOT的Pareto前沿与试验验证值之间的相对误差不超过8%,NO_(X)不超过5%,各工况下的R2均大于0.95。该方法改善了柴油机SOOT和NO_(X)之间的“Trade-off”关系,使柴油机排放性能得到提高。 展开更多
关键词 f-t煤制油 支持向量机 遗传算法 排放性能 多目标优化
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基于STM32F103C8T6的游乐场智能手环设计
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作者 朱扬 杨延宁 +2 位作者 董晨乐 冯树栋 杜永星 《计算机测量与控制》 2024年第9期213-219,248,共8页
针对当前游乐场管理效率低,游客体验感差等问题,设计了一种基于STM32F103C8T6的游乐场智能手环系统;利用STM32F103C8T6作为主控芯片、通过MAX30102心率传感器进行游客心率数据的采集,采样频率为每秒钟4次,并设置报警阈值;ESP8266WiFi模... 针对当前游乐场管理效率低,游客体验感差等问题,设计了一种基于STM32F103C8T6的游乐场智能手环系统;利用STM32F103C8T6作为主控芯片、通过MAX30102心率传感器进行游客心率数据的采集,采样频率为每秒钟4次,并设置报警阈值;ESP8266WiFi模块作为智能手环与服务器交流的传输媒介,调整工作模式为Station模式下,使用基于指纹匹配的定位算法实现WiFi定位;通过可以反复擦写与编程的XZ-T1010C型抗金属型RFID标签存储游客信息,实现了WiFi定位、自动计费、心率检测等功能;测试表明,设计的游乐场智能手环系统心率检测误差最大不超过3次/分钟,并能够很好地记录和保存游客信息,能够满足游客需求,提高游乐场管理效率,大大节省游乐场人力成本。 展开更多
关键词 游乐场 Wifi定位 智能手环 StM32f103C8t6 自动计费 心率检测
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F-T固废黏附特性调控及成浆特性研究
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作者 张利军 尹广华 +1 位作者 方伟 白红存 《炼油与化工》 CAS 2024年第2期23-25,共3页
F-T固废由含油铁基废催化剂和稳定渣蜡组成,含有55%~65%的蜡质组份,属于危废。文中通过将F-T固废与水煤浆气化装置煤粉进行共混复配,研究了F-T固废黏附特性调控,添加F-T固废的水煤浆表观黏度、静态稳定性等成浆性能,为在气化装置上掺烧... F-T固废由含油铁基废催化剂和稳定渣蜡组成,含有55%~65%的蜡质组份,属于危废。文中通过将F-T固废与水煤浆气化装置煤粉进行共混复配,研究了F-T固废黏附特性调控,添加F-T固废的水煤浆表观黏度、静态稳定性等成浆性能,为在气化装置上掺烧F-T固废,实现资源化利用提供了可靠的实验数据。结果表明:添加烷基酚聚氧乙烯醚或十二烷基苯磺酸钠,可以有效改善F-T固废的黏附特性;相同成浆浓度下,含有F-T固废的水煤浆表观黏度随固废含量增加而增大;当添加10%F-T固废,水煤浆最大成浆浓度由62.2%下降到了60.7%。 展开更多
关键词 f-t固废 气化煤粉 黏附特性 成浆特性
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核因子E2相关因子/血红素加氧酶1及血栓素B2T/6-酮-前列腺素F1α信号通路在宫颈癌根治术后发生深静脉血栓大鼠模型中的作用机制
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作者 莫明静 李得加 +1 位作者 张毅 朱桂娟 《陕西医学杂志》 CAS 2024年第10期1330-1334,共5页
目的:本研究旨在探讨核因子E2相关因子(Nrf2)/血红素加氧酶1(HO-1)及血栓素B2(TXB2)/6-酮-前列腺素F1α(6-Keto-PGF1α)信号通路在宫颈癌根治术后发生深静脉血栓大鼠模型中的作用机制。方法:购买60只4~6周龄裸鼠,体重(180±20)g,随... 目的:本研究旨在探讨核因子E2相关因子(Nrf2)/血红素加氧酶1(HO-1)及血栓素B2(TXB2)/6-酮-前列腺素F1α(6-Keto-PGF1α)信号通路在宫颈癌根治术后发生深静脉血栓大鼠模型中的作用机制。方法:购买60只4~6周龄裸鼠,体重(180±20)g,随机将60只大鼠分为空白对照组、模型组及深静脉血栓组各20只。其中空白组正常饲养1周;模型组及深静脉血栓组均建立宫颈癌动物模型,模型组造模成功后,正常饲养;深静脉血栓组给予宫颈癌根治术治疗,正常饲养。观察宫颈癌根治术后发生深静脉血栓HE染色切片,原位末端标记法(TUNEL)检测各组大鼠血管组织内皮细胞凋亡情况,全自动凝血分析仪检测各组大鼠凝血指标,酶联免疫吸附法测定TXB2/6-Keto-PGF1α水平,免疫印迹检测Nrf2/HO-1信号通路。结果:实验过程中,三组大鼠均未出现意外死亡,存活率均为100%。模型组未形成血栓,深静脉血栓组造模后1、3、7、14 d成栓率依次为50.00%(10/20)、95.00%(19/20)、100%(20/20)。大鼠下腔静脉产生的血栓尾部为红色血栓、中间为混合血栓、头部为白色血栓。深静脉血栓组血管内皮凋亡率高于模型组(P<0.05)。深静脉血栓组凝血酶时间、凝血酶原时间、活化部分凝血活酶时间低于模型组及空白对照组,D-二聚体高于模型组及空白对照组(均P<0.05);模型组凝血酶时间、凝血酶原时间、活化部分凝血活酶时间低于空白对照组,D-二聚体高于空白对照组(均P<0.05)。深静脉血栓组TXB2、TXB2/6-Keto-PGF1α高于模型组及空白对照组,6-Keto-PGF1α低于模型组及空白对照组(均P<0.05);模型组TXB2、TXB2/6-Keto-PGF1α高于空白对照组,6-Keto-PGF1α低于空白对照组(均P<0.05)。深静脉血栓组Nrf2、HO-1低于模型组及空白对照组,模型组Nrf2/HO-1低于空白对照组(均P<0.05)。结论:TXB2/6-Keto-PGF1α、Nrf2/HO-1信号通路在宫颈癌根治术后深静脉血栓大鼠中异常表达,也是宫颈癌根治术后深静脉血栓形成的作用机制之一。 展开更多
关键词 核因子E2相关因子/血红素加氧酶1 血栓素B2t/6-酮-前列腺素f 宫颈癌根治术后 深静脉血栓大鼠 机制
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外周血调节性T细胞及细胞因子IL-35、TGF-β和IL-10水平在血友病A抑制物阳性患者中的临床意义
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作者 和红霞 谢燕燕 +7 位作者 孙庆云 王霖虹 朱益文 李杰 王馨 邓昭玲 杨美荣 闫振宇 《中国实验血液学杂志》 CAS CSCD 北大核心 2024年第4期1197-1200,共4页
目的:探讨外周血调节性T细胞(Treg)及细胞因子IL-35、TGF-β和IL-10在血友病A(HA)抑制物阳性患者中的表达水平及临床意义。方法:选取2019年10月至2020年12月华北理工大学附属医院血液科收治的43例血友病A患者,其中抑制物阳性组6例,抑制... 目的:探讨外周血调节性T细胞(Treg)及细胞因子IL-35、TGF-β和IL-10在血友病A(HA)抑制物阳性患者中的表达水平及临床意义。方法:选取2019年10月至2020年12月华北理工大学附属医院血液科收治的43例血友病A患者,其中抑制物阳性组6例,抑制物阴性组37例;另外选取20例健康体检男性作为健康对照。应用流式细胞术检测抑制物阳性组、抑制物阴性组和健康对照组外周血CD4^(+)CD25^(+)CD127^(-)Treg细胞的水平,ELISA法检测血清IL-35、TGF-β和IL-10的表达水平,比较上述指标在各组间的差异。结果:与健康对照组相比,血友病A患者Treg细胞水平降低,且抑制物阳性组Treg细胞水平最低,差异具有统计学意义(P<0.05);Treg细胞表达水平在不同严重程度的患者中未见明显差异;抑制物阴性组和抑制物阳性组血清IL-35、TGF-β、IL-10水平均显著低于健康对照组,且抑制物阳性组显著低于抑制物阴性组(均P<0.05)。结论:血友病A患者Treg细胞、IL-35、TGF-β和IL-10水平的降低可能与抑制物的产生有关。 展开更多
关键词 血友病A fⅧ抑制物 调节性t细胞 细胞因子
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Absolute Measurement Fiber-optic Sensors inLarge Structural Monitoring 被引量:2
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作者 WANG Zhao-ying, WU Xing, TIAN He-bin, LI Shi-chen(College of Precision Instrum.and Optoelectron.Eng., Tianjin University, Tianjin 300072, CHN) 《Semiconductor Photonics and Technology》 CAS 2003年第2期102-106,共5页
The security of civil engineering is an important task due to the economic, social and environmental significance. Compared with conventional sensors, the optical fiber sensors have their unique characteristics.Being ... The security of civil engineering is an important task due to the economic, social and environmental significance. Compared with conventional sensors, the optical fiber sensors have their unique characteristics.Being durable, stable and insensitive to external perturbations,they are particular interesting for the long-term monitoring of civil structures.Focus is on absolute measurement optical fiber sensors, which are emerging from the monitoring large structural, including SOFO system, F-P optical fiber sensors, and fiber Bragg grating sensors. The principle, characteristic and application of these three kinds of optical fiber sensors are described together with their future prospects. 展开更多
关键词 SOfO system f―P fiber―optic sensors fizeau interferometer white―lightcross―correlator fiber bragg sensors large structure monitoring
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CHCHD2 Thr61Ile mutation impairs F1F0-ATPase assembly in in vitro and in vivo models of Parkinson's disease
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作者 Xiang Chen Yuwan Lin +14 位作者 Zhiling Zhang Yuting Tang Panghai Ye Wei Dai Wenlong Zhang Hanqun Liu Guoyou Peng Shuxuan Huang Jiewen Qiu Wenyuan Guo Xiaoqin Zhu Zhuohua Wu Yaoyun Kuang Pingyi Xu Miaomiao Zhou 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期196-204,共9页
Mitochondrial dysfunction is a significant pathological alte ration that occurs in Parkinson's disease(PD),and the Thr61lle(T61I)mutation in coiled-coil helix coiled-coil helix domain containing 2(CHCHD2),a crucia... Mitochondrial dysfunction is a significant pathological alte ration that occurs in Parkinson's disease(PD),and the Thr61lle(T61I)mutation in coiled-coil helix coiled-coil helix domain containing 2(CHCHD2),a crucial mitochondrial protein,has been reported to cause Parkinson's disease.FIFO-ATPase participates in the synthesis of cellular adenosine triphosphate(ATP)and plays a central role in mitochondrial energy metabolism.However,the specific roles of wild-type(WT)CHCHD2 and T611-mutant CHCHD2 in regulating F1FO-ATPase activity in Parkinson's disease,as well as whether CHCHD2 or CHCHD2 T61I affects mitochondrial function through regulating F1FO-ATPase activity,remain unclea r.Therefore,in this study,we expressed WT CHCHD2 and T61l-mutant CHCHD2 in an MPP^(+)-induced SH-SY5Y cell model of PD.We found that CHCHD2 protected mitochondria from developing MPP^(+)-induced dysfunction.Under normal conditions,ove rexpression of WT CHCHD2 promoted F1FO-ATPase assembly,while T61I-mutant CHCHD2 appeared to have lost the ability to regulate F1FO-ATPase assembly.In addition,mass spectrometry and immunoprecipitation showed that there was an interaction between CHCHD2 and F1FO-ATPase.Three weeks after transfection with AAV-CHCHD2 T61I,we intraperitoneally injected 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine into mice to establish an animal model of chronic Parkinson's disease and found that exogenous expression of the mutant protein worsened the behavioral deficits and dopaminergic neurodegeneration seen in this model.These findings suggest that WT CHCHD2 can alleviate mitochondrial dysfunction in PD by maintaining F1F0-ATPase structure and function. 展开更多
关键词 AtP synthase(f1f0-AtPase) coiled-coil helix coiled-coil helix domain containing 2 dopaminergic neuron mitochondrial dysfunction NEURODEGENERAtION oligomycin sensitivity-conferring protein Parkinson's disease t61I mutation tyrosine hydroxylase
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Quintessence anisotropic stellar models in quadratic and Born-Infeld modified teleparallel Rastall gravity
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作者 Allah Ditta 夏铁成 +1 位作者 Irfan Mahmood Asif Mahmood 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期179-189,共11页
This study aims to discuss anisotropic solutions that are spherically symmetric in the quintessence field,which describe compact stellar objects in the modified Rastall teleparallel theory of gravity.To achieve this g... This study aims to discuss anisotropic solutions that are spherically symmetric in the quintessence field,which describe compact stellar objects in the modified Rastall teleparallel theory of gravity.To achieve this goal,the Krori and Barua arrangement for spherically symmetric components of the line element is incorporated.We explore the field equations by selecting appropriate off-diagonal tetrad fields.Born-Infeld function of torsion f(T)=β√λT+1-1 and power law form h(T)=δTn are used.The Born-Infeld gravity was the first modified teleparallel gravity to discuss inflation.We use the linear equation of state pr=ξρto separate the quintessence density.After obtaining the field equations,we investigate different physical parameters that demonstrate the stability and physical acceptability of the stellar models.We use observational data,such as the mass and radius of the compact star candidates PSRJ 1416-2230,Cen X-3,&4U 1820-30,to ensure the physical plausibility of our findings. 展开更多
关键词 anisotropic spheres quintessence field modified Rastall teleparallel gravity equation of state(EoS) f(t)gravity
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Design of IoT-based Volatile Organic Compounds Monitoring System
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作者 Bo Wang Minghao Ma 《Journal of Electronic Research and Application》 2024年第3期161-171,共11页
Volatile organic compounds(VOC)gas detection devices based on semiconductor sensors have become a common method due to their low cost,simple principle,and small size.However,with the continuous development of material... Volatile organic compounds(VOC)gas detection devices based on semiconductor sensors have become a common method due to their low cost,simple principle,and small size.However,with the continuous development of materials science,various new materials have been applied in the fabrication of gas sensors,but these new materials have more stringent requirements for operating temperature,which cannot be met by existing sensor modules on the market.Therefore,this paper proposes a temperature-adjustable sensor module and designs an environmental monitoring system based on the STM32F103RET6 microprocessor.This system primarily utilizes multiple semiconductor gas sensors to monitor and record the concentrations of various harmful gases in different environments.It can also monitor real-time temperature,humidity,and latitude and longitude in the current environment,and upload the data to the Internet of Things via 4G communication.This system has the advantages of small size,portability,and low cost.Experimental results show that the sensor module can achieve precise control of operating temperature to a certain extent,with an average temperature error of approximately 3%.The monitoring system demonstrates a certain level of accuracy in detecting target gases and can promptly upload the data to a cloud platform for storage and processing.A comparison with professional testing equipment shows that the sensitivity curves of each sensor exhibit similarity.This study provides engineering and technical references for the application of VOC gas sensors. 展开更多
关键词 sensorS IOt Environmental monitoring VOC sensor StM32f103REt6
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Relationship Between Corrosion Level of Steel Bar and Diameter of Corroded Sensing Steel Wire in Wireless Sensor
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作者 许高娲 吴瑾 +1 位作者 王喆 陈镇 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第3期297-304,共8页
A kind of wireless sensor was previously developed,which is powered and transmit signals wirelessly instead of using an electrical connection to the embedded reinforcement.Based on this technique,the relationship betw... A kind of wireless sensor was previously developed,which is powered and transmit signals wirelessly instead of using an electrical connection to the embedded reinforcement.Based on this technique,the relationship between diameters of corroded sensing steel wires and corrosion levels of steel bars is established by experiments.Quadratic function is utilized to fit the experiment results,and the correlation coefficients are all larger than 0.95.Estimated corrosion levels of commonly used steel bars are given for different diameters of corroded sensing steel wires fractured due to corrosion. 展开更多
关键词 REINfORCEMENt CORROSION wireless sensor RESONANt f
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喷油特性对F-T煤制油压力振荡影响规律研究
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作者 冀冠佐 王铁 +1 位作者 石晋宏 王浩亚 《机械设计与制造》 北大核心 2024年第4期189-193,共5页
为了减小燃烧噪声,确定影响柴油机高频压力振荡的关键因素,在某型电控高压共轨柴油发动机上燃用的清洁代用燃料Fischer-Tropsch(F-T)煤制油,选取柴油机典型运行工况,研究不同喷油特性条件下柴油机燃烧压力振荡的时域和频域特性。结果表... 为了减小燃烧噪声,确定影响柴油机高频压力振荡的关键因素,在某型电控高压共轨柴油发动机上燃用的清洁代用燃料Fischer-Tropsch(F-T)煤制油,选取柴油机典型运行工况,研究不同喷油特性条件下柴油机燃烧压力振荡的时域和频域特性。结果表明:推后主喷提前角和提前预喷提前角会使放热率降低,压力振荡幅值减小,气缸压力级也有明显减小的趋势;减小预喷油量会使压力升高率和放热率降低,气缸声压级减小,压力振荡现象减缓,使燃烧更加柔和;提高喷射压力,会使喷油速率增大,燃油雾化效果增强,混合气放热率提升,放热率曲线也随之上升,气缸声压级增大,发动机缸内燃烧压力振荡幅值增大。喷射压力是影响压力振荡的最显著的参数,喷射压力从85MPa上升至115MPa时,压力振荡幅值增加一倍以上;预喷油量对F-T煤制油发动机的燃烧压力振荡影响不显著;同时压力振荡的产生与放热率的变化呈现出较强的相关性。 展开更多
关键词 高压共轨柴油机 f-t煤制油 燃烧特性 压力振荡 喷油特性
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A Chopper Negative-R Delta-Sigma ADC for Audio MEMS Sensors
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作者 Jamel Nebhen Pietro M.Ferreira 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第2期607-631,共25页
This paper presents a proposed low-noise and high-sensitivity Internet of Thing(IoT)system based on an M&NEMS microphone.The IoT device consists of an M&NEMS resistive accelerometer associated with an electron... This paper presents a proposed low-noise and high-sensitivity Internet of Thing(IoT)system based on an M&NEMS microphone.The IoT device consists of an M&NEMS resistive accelerometer associated with an electronic readout circuit,which is a silicon nanowire and a Continuous-Time(CT)△∑ADC.The first integrator of the△∑ADC is based on a positive feedback DC-gain enhancement two-stage amplifier due to its high linearity and low-noise operations.To mitigate both the offset and 1/f noise,a suggested delay-time chopper negative-R stabilization technique is applied around the first integrator.A 65-nm CMOS process implements the CT△∑ADC.The supply voltage of the CMOS circuit is 1.2-V while 0.96-mW is the power consumption and 0.1-mm^(2) is the silicon area.The M&NEMS microphone and△∑ADC complete circuit are fabricated and measured.Over a working frequency bandwidth of 20-kHz,the measurement results of the proposed IoT system reach a signal to noise ratio(SNR)of 102.8-dB.Moreover,it has a measured dynamic range(DR)of 108-dB and a measured signal to noise and distortion ratio(SNDR)of 101.3-dB. 展开更多
关键词 M&NEMS sensor △∑ ADC chopper negative-R Iot 1/f noise SNR
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基于STM32F103C8T6控制的智能水上救生装置的研究
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作者 郭珊 刘彧祺 《模具制造》 2024年第10期187-190,共4页
传统水上救生装置体积庞大、不易搬运,针对这些问题,设计一种体积小、重量轻,并且可远程操控制动,能够稳定运行的水上救生装置系统。本系统由无线遥控和救生船体两部分组成,两者之间通信由HC-12模块负责;船体主控核心部件选用STM32F103C... 传统水上救生装置体积庞大、不易搬运,针对这些问题,设计一种体积小、重量轻,并且可远程操控制动,能够稳定运行的水上救生装置系统。本系统由无线遥控和救生船体两部分组成,两者之间通信由HC-12模块负责;船体主控核心部件选用STM32F103C8T6最小单片机系统板,可处理控制信号以及热释电红外传感技术采集的被施救者位置等信息,产生所需要的控制指令,利用电机驱动控制电机转动,从而控制船体的运动状态。由于风浪影响,导致救生装置偏转方向,造成控制不稳定的问题,可利用PID控制技术解决。 展开更多
关键词 水上救生装置 无线遥控 StM32f103C8t6 热释电红外传感技术 PID
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An integrated front-end vertical hall magnetic sensor fabricated in 0.18μm low-voltage CMOS technology
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作者 Zhengwu Shu Lei Jiang +1 位作者 Xingxing Hu Yue Xu 《Journal of Semiconductors》 EI CAS CSCD 2022年第3期60-67,共8页
An integrated front-end vertical CMOS Hall magnetic sensor is proposed for the in-plane magnetic field measure-ment.To improve the magnetic sensitivity and to obtain low offset,a fully symmetric vertical Hall device(F... An integrated front-end vertical CMOS Hall magnetic sensor is proposed for the in-plane magnetic field measure-ment.To improve the magnetic sensitivity and to obtain low offset,a fully symmetric vertical Hall device(FSVHD)has been op-timized with a minimum size design.A new four-phase spinning current modulation associated with a correlated double sampling(CDS)demodulation technique has been further applied to compensate for the offset and also to provide a linear Hall output voltage.The vertical Hall sensor chip has been manufactured in a 0.18μm low-voltage CMOS technology and it occu-pies an area of 1.54 mm2.The experimental results show in the magnetic field range from-200 to 200 mT,the entire vertical Hall sensor performs with the linearity of 99.9%and the system magnetic sensitivity of 1.22 V/T and the residual offset of 60μT.Meanwhile,it consumes 4.5 mW at a 3.3 V supply voltage.The proposed vertical Hall sensor is very suitable for the low-cost sys-tem-on-chip(SOC)implementation of 2D or 3D magnetic microsystems. 展开更多
关键词 vertical Hall sensor dynamic offset cancellation 1/f noise residual offset
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Design of C8051F350-based Intelligent Pressure Sensor
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作者 韩丽娜 陶安利 +3 位作者 李绍刚 柳军国 厉运周 李相众 《Journal of Measurement Science and Instrumentation》 CAS 2011年第2期157-160,共4页
In order to overcome the deficiencies of traditional pressure sensors, a kind of intelligent pressure sensors with temperature correction is designed. Qccording to the intelligent sensor system of composition and rang... In order to overcome the deficiencies of traditional pressure sensors, a kind of intelligent pressure sensors with temperature correction is designed. Qccording to the intelligent sensor system of composition and range of applications, with fully taking into account the parameters of the connection between of co-ordination, we chose a good usability, high reliability and low cost components composed of the entire measurement system, with controlling and dealing with in 80C51 miller, the system had the temperature and pressure parameters with automatic measurement, amplification, A/D conversion, the weak signal locked amplification, as well as PhaseSensitive Detection (PSD), common-mode signal rejection, the collected signal de-noising processing, cross-sensitivity of the decoupling and show the results. It also has a self-test, automatic temperature condition and on, site communications and other functions. 展开更多
关键词 pressure sensor Lock-in Amplifier 80C51f350 SCM hardware circuitry
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Study on Refraction Index Sensors Using Fiber Grating F-P Cavity
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作者 MAO Kai, QU Li, SU Xuemei (College of Physics, Jilin University, Changchun 130023, CHN) 《Semiconductor Photonics and Technology》 CAS 2010年第4期146-149,166,共5页
In this paper, the reflective spectra of a refraction index sensor were analyzed based on fiber grating F-P cavity. The sensor was constituted by two identical fiber gratings. Compared with the refraction index sensor... In this paper, the reflective spectra of a refraction index sensor were analyzed based on fiber grating F-P cavity. The sensor was constituted by two identical fiber gratings. Compared with the refraction index sensor using one fiber grating, the fiber grating F-P cavity sensor has narrower resonant peak and it can be used for more accurate measurement. The resonant peaks in the reflective spectra of the sensor are changed with small changes of the refraction index of the measured chemical liquids or cell samples. So it has potential applications in biology and chemistry. 展开更多
关键词 sensor fiber BRAGG GRAtING f-P CAVItY MAtRIX EQUAtION
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F-T柴油在直喷式柴油机中燃烧与排放特性的研究 被引量:17
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作者 黄勇成 李永旺 +1 位作者 任杰 周龙保 《燃料化学学报》 EI CAS CSCD 北大核心 2005年第4期492-496,共5页
煤通过FischerTropsch(FT)合成可得到十六烷值高、硫和芳香烃质量分数极低的FT柴油。研究分析了未作改动的单缸直喷式柴油机燃用FT柴油时的燃烧和排放特性。结果表明,与燃用0号柴油相比,燃用FT柴油时的滞燃期平均缩短18.7%,预混燃烧放... 煤通过FischerTropsch(FT)合成可得到十六烷值高、硫和芳香烃质量分数极低的FT柴油。研究分析了未作改动的单缸直喷式柴油机燃用FT柴油时的燃烧和排放特性。结果表明,与燃用0号柴油相比,燃用FT柴油时的滞燃期平均缩短18.7%,预混燃烧放热峰值降低26.8%,扩散燃烧放热峰值较高,燃烧持续期相当。燃用FT柴油时的最高燃烧压力略低,最大压力升高率显著下降,机械损失和燃烧噪音较小,燃油消耗率和热效率都得到显著改善。燃用FT柴油可同时降低CO、HC、NOx和炭烟排放,其中NOx和炭烟分别平均降低16.7%和40.3%。研究表明,FT柴油是柴油机良好的清洁代用燃料。 展开更多
关键词 ft柴油 清洁代用燃料 直喷式柴油机 燃烧 排放
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联合检测F-PSA、T-PSA及F-PSA/T-PSA比值在前列腺疾病诊断中的意义 被引量:13
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作者 赵乔妹 时宇 +1 位作者 张静 王海滨 《标记免疫分析与临床》 CAS 2015年第6期487-489,共3页
目的 探讨血清游离前列腺特异性抗原(F-PSA)、总前列腺特异性抗原(T-PSA)和F-PSA/T-PSA比值在前列腺疾病诊断中的意义.方法 选取2012年10月至2014年10月我院泌尿外科的前列腺疾病患者190例.通过化学发光法测定其血清中F-PSA、T-PSA... 目的 探讨血清游离前列腺特异性抗原(F-PSA)、总前列腺特异性抗原(T-PSA)和F-PSA/T-PSA比值在前列腺疾病诊断中的意义.方法 选取2012年10月至2014年10月我院泌尿外科的前列腺疾病患者190例.通过化学发光法测定其血清中F-PSA、T-PSA的含量,计算F-PSA/T-PSA比值,并与100例健康体检者进行比较.结果 前列腺增生(BPH)组和前列腺癌(PCa)组F-PSA、T-PSA均显著高于正常对照组(P<0.01); PCa患者组与BPH患者组差异亦存在统计学意义(P<0.01).当T-PSA在4~ 10 ng/mL之间时,BPH患者组和PCa患者组T-PSA水平差异无统计学意义(P>0.05);但PCa患者组F-PSA/T-PSA明显低于BPH患者组,差异具有统计学意义(P<0.01).结论 同时检测F-PSA、T-PSA并计算F-PSA/T-PSA比值明显优于单纯检测T-PSA,在前列腺疾病的鉴别诊断中具有重要的意义. 展开更多
关键词 前列腺癌 良性前列腺增生 f—PSA t—PSA 诊断
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