核酸测量在生物安全、医疗健康、食品安全、环境监测等多个领域具有重要应用,因此核酸测量结果的准确和可靠至关重要。核酸计量是关于核酸测量及其应用的学科,是研究核酸计量单位统一和量值准确可靠的生物计量分支。综述了国际化学和生...核酸测量在生物安全、医疗健康、食品安全、环境监测等多个领域具有重要应用,因此核酸测量结果的准确和可靠至关重要。核酸计量是关于核酸测量及其应用的学科,是研究核酸计量单位统一和量值准确可靠的生物计量分支。综述了国际化学和生物计量咨询委员会(Consultative Committee for Amount of Substance Metrology in Chemistry and Biology, CCQM)核酸分析工作组(Nucleic Acid Analysis Working Group, NAWG)在提高核酸分析测量结果准确、可靠和可比方面所做的工作。NAWG是一个致力于提高核酸测量结果可比性的国际组织,其主要工作是为核酸测量能力的维持与发展提供支持。近20年来,NAWG成员开展了一系列研究工作,为不同领域的核酸测量结果的准确、一致和可溯源提供了支持。展开更多
2024年4月,由中国科学院声学研究所东海研究站与大连检验检测认证集团有限公司联合共建的“水声检测与感知实验室”正式通过中国合格评定国家认可委员会(China National Accreditation Service for Conformity Assessment,CNAS)实验室认...2024年4月,由中国科学院声学研究所东海研究站与大连检验检测认证集团有限公司联合共建的“水声检测与感知实验室”正式通过中国合格评定国家认可委员会(China National Accreditation Service for Conformity Assessment,CNAS)实验室认可,这标志着上海首家获得CNAS认可的水声检测实验室正式投入运行。水声检测与感知实验室获CNAS认可的校准和测量能力范围包括标准水听器、水声换能器等水声测量仪器的校准,认可的检测能力范围包括水声换能器等水声测量仪器设备、水下噪声等水声参数的检测。展开更多
针对Hubing电流驱动模型中认为电流在辐射线缆中是均一分布的,幅值和相位保持不变即未考虑辐射线缆共模电流频率效应给辐射电磁干扰噪声预估带来的误差的问题.文中利用电流传输波动特性建立了辐射线缆长度与共模电流波长为同一数量级时...针对Hubing电流驱动模型中认为电流在辐射线缆中是均一分布的,幅值和相位保持不变即未考虑辐射线缆共模电流频率效应给辐射电磁干扰噪声预估带来的误差的问题.文中利用电流传输波动特性建立了辐射线缆长度与共模电流波长为同一数量级时的辐射线缆共模电流分布模型,并设计电路模型进行测试预估.实验结果表明:采用文中方法预估辐射电磁干扰噪声与Hubing电流驱动模型预估方法相比能提高20.12dB_μV/m,更加接近标准暗室测试结果,从而为辐射电磁干扰(Electro Magnetic Interference,EMI)测试与分析提供理论依据.展开更多
Due to the intense vibration durirLg launching and rigorous orbital temperature environment, the kinematic parameters of space robot may be largely deviated from their nominal parameters. The disparity will cause the ...Due to the intense vibration durirLg launching and rigorous orbital temperature environment, the kinematic parameters of space robot may be largely deviated from their nominal parameters. The disparity will cause the real pose (including position and orientation) of the end effector not to match the desired one, and further hinder the space robot from performing the scheduled mission. To improve pose accuracy of space robot, a new self-calibration method using the distance measurement provided by a laser-ranger fixed on the end-effector is proposed. A distance-measurement model of the space robot is built according to the distance from the starting point of the laser beam to the intersection point at the declining plane. Based on the model, the cost function about the pose error is derived. The kinematic calibration is transferred to a non-linear system optimization problem, which is solved by the improved differential evolution (DE) algoritlun. A six-degree of freedom (6-DOF) robot is used as a practical simulation example, and the simulation results show: 1) A significant improvement of pose accuracy of space robot can be obtained by distance measurement only; 2) Search efficiency is increased by improved DE; 3) More calibration configurations may make calibration results better.展开更多
文摘核酸测量在生物安全、医疗健康、食品安全、环境监测等多个领域具有重要应用,因此核酸测量结果的准确和可靠至关重要。核酸计量是关于核酸测量及其应用的学科,是研究核酸计量单位统一和量值准确可靠的生物计量分支。综述了国际化学和生物计量咨询委员会(Consultative Committee for Amount of Substance Metrology in Chemistry and Biology, CCQM)核酸分析工作组(Nucleic Acid Analysis Working Group, NAWG)在提高核酸分析测量结果准确、可靠和可比方面所做的工作。NAWG是一个致力于提高核酸测量结果可比性的国际组织,其主要工作是为核酸测量能力的维持与发展提供支持。近20年来,NAWG成员开展了一系列研究工作,为不同领域的核酸测量结果的准确、一致和可溯源提供了支持。
文摘2024年4月,由中国科学院声学研究所东海研究站与大连检验检测认证集团有限公司联合共建的“水声检测与感知实验室”正式通过中国合格评定国家认可委员会(China National Accreditation Service for Conformity Assessment,CNAS)实验室认可,这标志着上海首家获得CNAS认可的水声检测实验室正式投入运行。水声检测与感知实验室获CNAS认可的校准和测量能力范围包括标准水听器、水声换能器等水声测量仪器的校准,认可的检测能力范围包括水声换能器等水声测量仪器设备、水下噪声等水声参数的检测。
文摘针对Hubing电流驱动模型中认为电流在辐射线缆中是均一分布的,幅值和相位保持不变即未考虑辐射线缆共模电流频率效应给辐射电磁干扰噪声预估带来的误差的问题.文中利用电流传输波动特性建立了辐射线缆长度与共模电流波长为同一数量级时的辐射线缆共模电流分布模型,并设计电路模型进行测试预估.实验结果表明:采用文中方法预估辐射电磁干扰噪声与Hubing电流驱动模型预估方法相比能提高20.12dB_μV/m,更加接近标准暗室测试结果,从而为辐射电磁干扰(Electro Magnetic Interference,EMI)测试与分析提供理论依据.
基金Projects(60775049,60805033) supported by National Natural Science Foundation of ChinaProject(2007AA704317) supported by the National High Technology Research and Development Program of China
文摘Due to the intense vibration durirLg launching and rigorous orbital temperature environment, the kinematic parameters of space robot may be largely deviated from their nominal parameters. The disparity will cause the real pose (including position and orientation) of the end effector not to match the desired one, and further hinder the space robot from performing the scheduled mission. To improve pose accuracy of space robot, a new self-calibration method using the distance measurement provided by a laser-ranger fixed on the end-effector is proposed. A distance-measurement model of the space robot is built according to the distance from the starting point of the laser beam to the intersection point at the declining plane. Based on the model, the cost function about the pose error is derived. The kinematic calibration is transferred to a non-linear system optimization problem, which is solved by the improved differential evolution (DE) algoritlun. A six-degree of freedom (6-DOF) robot is used as a practical simulation example, and the simulation results show: 1) A significant improvement of pose accuracy of space robot can be obtained by distance measurement only; 2) Search efficiency is increased by improved DE; 3) More calibration configurations may make calibration results better.