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The value of ultrasound elastography in differential diagnosis of superficial lymph nodes

Yanrong ZHANG phD , Qing LV MD , Mingxing XIE MD , Feixiang XIANG phD , Chengfa LU BM , Tianwei YAN BM , Wei LI BM , Hui XU BM , Yan HUANG BM , Yehua YIN BM ,

《医学前沿（英文）》 2009年第3卷第3期页码 368-374 doi: 10.1007/s11684-009-0063-0

摘要： The study evaluated the value of ultrasound elastography in differentiating the benign and malignant superficial lymph nodes. A total of 112 subjects, including 82 patients with enlarged lymph nodes and 30 healthy volunteers, were recruited. All the subjects were examined by B-mode ultrasonography, power Doppler ultrasonography and elastography. Most of the patients were histopathologically confirmed by needle aspiration cytology and some patients were diagnosed by clinical data combined with follow-up findings. The sensitivity, specificity and accuracy of B-mode ultrasonography were 59.8%, 76.5% and 67.1%, those of the blood flow classification by power Doppler ultrasonography 77.0%, 82.3% and 79.4% and those of elastographic classification 74.7%, 97.1% and 84.5%, respectively. The elasticity of the lymph nodes was quantitatively measured and defined as stiffness value. When the stiffness value of 2.395 was taken as the cutoff point, the sensitivity and specificity of elastography were 78.41% and 98.51%, and the Youden index reached the highest, with the value being 0.7692. The stiffness values of two indeterminate benign lymph nodes, the elastrographic findings of which were rated as patterns 2 and 3, were below the cutoff point. The elastographic findings of 10 malignant lymph nodes were also classified as pattern 2 or 3. Only one of them had the stiffness values below the cutoff point. It was concluded that ultrasound elastography is a novel, noninvasive and convenient tool for the differentiation of the nature of the superficial lymph nodes in clinical practice.

关键词： ultrasound elastography lymph node power Doppler sonography

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中国新一代多普勒天气雷达网的建设与技术应用

许小峰

《中国工程科学》 2003年第5卷第6期页码 7-14

摘要：

新一代多普勒天气雷达已成为对灾害性天气监测、预测的重要手段之一，世界上一些发达国家已普遍使用这一技术。我国从1998年开始建设新一代天气雷达网，已将这项工程列入国债资金支持项目。介绍了多普勒天气雷达的技术发展情况，目前我国的建设和应用情况，提出在发展建设中应注意的几个问题，以及未来雷达技术在天气监测中的若干发展和应用领域。

关键词：新一代多普勒天气雷达技术分析系统建设与应用未来发展

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毫米波调频步进雷达运动补偿方法研究

王桂丽,李兴国

《中国工程科学》 2008年第10卷第7期页码 184-187

摘要：文章提出了一种把脉冲多普勒（Pulse Doppler）测速和基于Chirp-SF信号的时域相关法测速相复合的方法。仿真结果表明该方法测速精度高，算法简单，速度快。

关键词：毫米波雷达调频步进多普勒运动补偿

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UPFC setting to avoid active power flow loop considering wind power uncertainty

Shenghu LI, Ting WANG

《能源前沿（英文）》 2023年第17卷第1期页码 165-175 doi: 10.1007/s11708-020-0686-z

摘要： The active power loop flow (APLF) may be caused by impropriate network configuration, impropriate parameter settings, and/or stochastic bus powers. The power flow controllers, e.g., the unified power flow controller (UPFC), may be the reason and the solution to the loop flows. In this paper, the critical existence condition of the APLF is newly integrated into the simultaneous power flow model for the system and UPFC. Compared with the existing method of alternatively solving the simultaneous power flow and sensitivity-based approaching to the critical existing condition, the integrated power flow needs less iterations and calculation time. Besides, with wind power fluctuation, the interval power flow (IPF) is introduced into the integrated power flow, and solved with the affine Krawcyzk iteration to make sure that the range of active power setting of the UPFC not yielding the APLF. Compared with Monte Carlo simulation, the IPF has the similar accuracy but less time.

关键词： active power loop flow (APLF) unified power flow controller (UPFC) wind power uncertainty interval power flow (IPF)

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基于一种全新的优化多变量非等距模型对中国汉族成人左心室多普勒超声心动图测值生理性变异的校正方法 Article

姚桂华, 陈湘云, 杨文静, 张青, 刘静, 梁欢, 孙慧, 许耀, 王丽, 徐金锋, 张澄, 孙丰荣, 张梅, 曾雪迎, 张运

《工程（英文）》 2022年第16卷第9期页码 115-122 doi: 10.1016/j.eng.2021.05.007

摘要：

多数左心室（LV）多普勒超声心动图参数测值随年龄和性别显著变化，因此有必要对其生理性差异进行校正。本研究旨在验证：不同的多普勒参数测值与生物学特征变量间呈异速非线性相关，且其校正常数与校正指数各不同。共测量了1224名健康成人的23个LV多普勒参数。随机选择70%数据（A组）建立优化多变量非线性模型（OMAM），在30%数据（B组）和183名超重人群数据（C组）中验证OMAM的可靠性，并与基于体表面积（BSA）的单变量等距模型（SVIM）进行比较。结果显示，校正前，23个LV多普勒参数均与一个或多个生物学特征变量显著相关，B组中47.8% (11/23)的参数存在性别间差异，经OMAM校正后，81.8% (9/11)的参数消除了性别间差异。OMAM对B组和C组数据的校正成功率分别为100% (23/23)和82.6% (19/23)，建立了独立于生物学特征变量的多普勒参数的OMAM参考值，而基于BSA的SVIM校正成功率为零。不同的LV多普勒参数与一个或多个生物学特征变量呈异速非线性相关；本研究建立的OMAM成功校正了因生物学特征变量差异对健康和超重人群多普勒测值的生理性影响，其校正效果显著优于传统的SVIM。然而，OMAM针对其他种族、肥胖和疾病状态人群的适用性仍需进一步探究

关键词：多普勒超声心动图生理性变异非等距模型正常参考值

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自适应最优相关间隔选择的多普勒频偏估计算法

张彭,毕光国,曹秀英,袁晓辉

《中国工程科学》 2007年第9卷第6期页码 71-76

摘要：

在信道自相关特性的多普勒频偏估计算法的基础上，分析了存在的估计性能不受信噪比和频偏变化影响的最优相关间隔。利用该特性提出一种逐次缩小搜索范围的迭代（CIO，correlation唱interval optimized）算法，实现对其搜索和最大多普勒频偏的估计。通过仿真证明理论分析的正确及算法的有效性。与传统基于相关估计算法相比，该算法自适应于信噪比和频偏变化，估计性能基本上独立于信噪比和频偏的变化，实现多普勒频偏的直接性能估计。

关键词：多普勒频偏自相关最优化迭代

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LTE外辐射源雷达多普勒维模糊副峰分析及抑制 Research Articles

左罗,王俊,陈刚

《信息与电子工程前沿（英文）》 2021年第22卷第8期页码 1140-1152 doi: 10.1631/FITEE.2000143

摘要：本文详细介绍了LTE频分物理下行链路信号(LTE信号)作为照射源的外辐射雷达系统。根据LTE信号特定的物理帧结构分析其模糊函数特性，同时探讨多普勒维不同类型副峰的形成机理。提出一种基于自适应参考信号预处理的失配滤波方法求解模糊权值因子，抑制模糊副峰的影响，提高目标检测性能。仿真结果表明所提方法可将副峰抑制至−40 dB以下，同时主峰损失仅为1.7 dB，验证了所提算法有效性。

关键词：外辐射源雷达（PBR）；长期演进（LTE）；多普勒模糊副峰；距离多普勒二维联合

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Possible role of power-to-heat and power-to-gas as flexible loads in German medium voltage networks

Mark KUPRAT, Martin BENDIG, Klaus PFEIFFER

《能源前沿（英文）》 2017年第11卷第2期页码 135-145 doi: 10.1007/s11708-017-0472-8

摘要： Germany’s energy transition triggered a rapid and unilateral growth of renewable energy sources (RES) in the electricity sector. With increasing shares of intermittent RES, overcapacities during periods of strong wind and photovoltaic electricity generation occur. In the face of insufficient transmission capacities, due to an inhibited network extension, the electricity generation has to be curtailed. This curtailment of RES leads to economic losses and could be avoided through flexible loads. As an option to cope with those problems, the technologies of power-to-gas (PtG) and power-to-heat (PtH) are presented in this paper. First, the alkaline electrolyzer (AEL), polymer electrolyte membrane electrolyzer (PEMEL), and solid oxide electrolyzer cell (SOEC) are investigated regarding their operational parameters. Second, the electric boiler, electrode heating boiler, and heat pumps are considered. Ultimately, the network-supporting abilities and the potential to provide ancillary services, such as control power, load sequence operation, cold start and part load capability, are compared among one another.

关键词： power-to-gas power-to-heat flexible loads ancillary services coherent energy systems

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一种面向地面区域检测和目标跟踪的多传感器系统协同调度方法 Research Article

张昀普,付强,单甘霖

《信息与电子工程前沿（英文）》 2023年第24卷第2期页码 245-258 doi: 10.1631/FITEE.2200121

摘要：本文提出一种面向多任务协同的多传感器系统协同调度方法，并将其应用于地面区域检测和目标跟踪。调度的目的是选择最佳的传感器来完成分配的作战任务，并获得最佳作战收益。首先建立区域检测模型，并提出检测风险的计算方法以量化在调度中的检测收益。然后结合道路约束信息和多普勒盲区信息建立地面目标跟踪模型，并引入后验克拉美罗下限评估未来时刻的跟踪精度。最后，考虑检测、跟踪和能耗控制的需求建立目标函数，通过求解目标函数，得到最优的传感器调度方案。仿真结果表明，所提传感器调度方法可以选择合适的传感器完成所需作战任务，并在区域检测、目标跟踪和能耗控制方面均具有良好性能。

关键词：传感器调度；区域检测；目标跟踪；道路约束；多普勒盲区

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Evaluation of the power-generation capacity of wearable thermoelectric power generator

Yang YANG, Jing LIU,

《能源前沿（英文）》 2010年第4卷第3期页码 346-357 doi: 10.1007/s11708-010-0112-z

摘要： Employing thermoelectric generators (TEGs) to gather heat dissipating from the human body through the skin surface is a promising way to supply electronic power to wearable and pocket electronics. The uniqueness of this method lies in its direct utilization of the temperature difference between the environment and the human body, and complete elimination of power maintenance problems. However, most of the previous investigations on thermal energy harvesters are confined to the TEG and electronic system themselves because of the low quality of human energy. We evaluate the energy generation capacity of a wearable TEG subject to various conditions based on biological heat transfer theory. Through numerical simulation and corresponding parametric studies, we find that the temperature distribution in the thermopiles affects the criterion of the voltage output, suggesting that the temperature difference in a single point can be adopted as the criterion for uniform temperature distribution. However, the criterion has to be shifted to the sum of temperature difference on each thermocouple when the temperature distribution is inconsistent. In addition, the performance of the thermal energy harvester can be easily influenced by environmental conditions, as well as the physiological state and physical characteristics of the human body. To further validate the calculation results for the wearable TEG, a series of conceptual experiments are performed on a number of typical cases. The numerical simulation provides a good overview of the electricity generation capability of the TEG, which may prove useful in the design of future thermal energy harvesters.

关键词： thermal energy harvester thermoelectric generator biological heat transfer power generating capacity

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Renewable power for China: Past, present, and future

Eric MARTINOT

《能源前沿（英文）》 2010年第4卷第3期页码 287-294 doi: 10.1007/s11708-010-0120-z

摘要： This paper briefly examines the history, status, policy situation, development issues, and prospects for key renewable power technologies in China. The country has become a global leader in wind turbine and solar photovoltaic (PV) production, and leads the world in total power capacity from renewable energy. Policy frameworks have matured and evolved since the landmark 2005 Renewable Energy Law, updated in 2009. China’s 2020 renewable energy target is similar to that of the EU. However, China continues to face many challenges in technology development, grid-integration, and policy frameworks. These include training, research and development, wind turbine operating experience and performance, transmission constraints, grid interconnection time lags, resource assessments, power grid integration on large scales, and continued policy development and adjustment. Wind and solar PV targets for 2020 will likely be satisfied early, although domestic demand for solar PV remains weak and the pathways toward incorporating distributed and building-integrated solar PV are uncertain. Prospects for biomass power are limited by resource constraints. Other technologies such as concentrating solar thermal power, ocean energy, and electricity storage require greater attention.

关键词： renewable energy wind power solar power sustainable energy policy green industry

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Carbon emission impact on the operation of virtual power plant with combined heat and power system

Yu-hang XIA,Jun-yong LIU,Zheng-wen HUANG,Xu ZHANG

《信息与电子工程前沿（英文）》 2016年第17卷第5期页码 479-488 doi: 10.1631/FITEE.1500467

摘要： A virtual power plant (VPP) can realize the aggregation of distributed generation in a certain region, and represent distributed generation to participate in the power market of the main grid. With the expansion of VPPs and ever-growing heat demand of consumers, managing the effect of fluctuations in the amount of available renewable resources on the operation of VPPs and maintaining an economical supply of electric power and heat energy to users have been important issues. This paper proposes the allocation of an electric boiler to realize wind power directly converted for supplying heat, which can not only overcome the limitation of heat output from a combined heat and power (CHP) unit, but also reduce carbon emissions from a VPP. After the electric boiler is considered in the VPP operation model of the combined heat and power system, a multi-objective model is built, which includes the costs of carbon emissions, total operation of the VPP and the electricity traded between the VPP and the main grid. The model is solved by the CPLEX package using the fuzzy membership function in Matlab, and a case study is presented. The power output of each unit in the case study is analyzed under four scenarios. The results show that after carbon emission is taken into account, the output of low carbon units is significantly increased, and the allocation of an electric boiler can facilitate the maximum absorption of renewable energy, which also reduces carbon emissions from the VPP.

关键词： Virtual power plant (VPP) Carbon emissions Electric boiler Wind power Combined heat and power (CHP)

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基于对称多项式辅助的中国余数定理的脉冲多普勒雷达多目标距离估计算法 Research Articles

曹成虎1,赵永波1,2

《信息与电子工程前沿（英文）》 2022年第23卷第2期页码 304-316 doi: 10.1631/FITEE.2000418

摘要：工作在高脉冲重复频率的脉冲多普勒雷达能避免多普勒模糊，但是高脉冲重复频率在许多场合导致距离模糊。目前，解决距离模糊的有效方案是基于波形设计，但是增加了雷达系统的复杂性。由于目标距离和量测距离的对应关系未知，传统的基于多脉冲重复频率方案，特别是中国余数定理，很难应用于多目标距离解模糊。本文旨在研究量测距离含有误差的基于中国余数定理多目标距离估计方法。提出基于对称多项式辅助的中国余数定理，能有效从含有误差的量测距离中重建多目标距离。封闭式鲁棒中国余数定理和基于Aitken加速算法的多项式方程求解方法能有效降低所提算法的计算复杂度。

关键词：距离模糊；误差距离；多目标；对称多项式辅助的中国余数定理

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制造质量强国战略

“制造质量强国战略研究”课题组

《中国工程科学》 2015年第17卷第7期页码 24-28

摘要：

本文系统论述了实现制造质量强国战略的意义，分析了我国制造业质量发展的现状，借鉴主要工业国家质量发展经验并针对中国国情，提出了到2025年制造质量强国的战略目标、战略任务、战略对策和政策建议。

关键词：制造强国质量战略

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Will Germany move into a situation with unsecured power supply?

Harald SCHWARZ

《能源前沿（英文）》 2019年第13卷第3期页码 551-570 doi: 10.1007/s11708-019-0641-z

摘要： Together with a huge number of other countries, Germany signed the Paris Agreements in 2015 to prevent global temperature increase above 2°C. Within this agreement, all countries defined their own national contributions to CO reduction. Since that, it was visible that CO emissions in Germany decreased, but not so fast than proposed in this German nationally determined contribution to the Paris Agreement. Due to increasing traffic, CO emissions from this mobility sector increased and CO emission from German power generation is nearly constant for the past 20 years, even a renewable generation capacity of 112 GW was built up in 2017, which is much higher than the peak load of 84 GW in Germany. That is why the German National Government has implemented a commission (often called “The German Coal Commission”) to propose a time line: how Germany can move out of coal-fired power stations. This “Coal Commission” started its work in the late spring of 2018 and handed over its final report with 336 pages to the government on January 26th, 2019. Within this report the following proposals were made: ① Until 2022: Due to a former decision of the German Government, the actual remaining nuclear power generation capacity of about 10 GW has to be switched off in 2022. Besides, the “Coal Commission” proposed to switch off additionally in total 12.5 GW of both, hard coal and lignite-fired power plants, so that Germany should reduce its conventional generation capacity by 22.5 GW in 2022. ② Until 2030: Another 13 GW of German hard coal or lignite-fired power plants should be switched off. ③ Until 2038: The final 17 GW of German hard coal or lignite-fired power plants should be switched off until 2038 latest. Unfortunately the “Coal Commission” has not investigated the relevant technical parameter to ensure a secured electric power supply, based on German’s own national resources. Because German Energy Revolution mainly is based on wind energy and photovoltaic, this paper will describe the negligible contribution of these sources to the secured generation capacity, which will be needed for a reliable power supply. In addition, it will discuss several technical options to integrate wind energy and photovoltaic into a secured power supply system with an overall reduced CO emission.

关键词： CO₂ reduction mobility sector renewable generation coal commission secured power generation capacity reliable power supply power-to-gas power-to-heat

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标题作者时间类型操作

The value of ultrasound elastography in differential diagnosis of superficial lymph nodes

Yanrong ZHANG phD , Qing LV MD , Mingxing XIE MD , Feixiang XIANG phD , Chengfa LU BM , Tianwei YAN BM , Wei LI BM , Hui XU BM , Yan HUANG BM , Yehua YIN BM ,

期刊论文

中国新一代多普勒天气雷达网的建设与技术应用

许小峰

期刊论文

毫米波调频步进雷达运动补偿方法研究

王桂丽,李兴国

期刊论文

UPFC setting to avoid active power flow loop considering wind power uncertainty

Shenghu LI, Ting WANG

期刊论文

基于一种全新的优化多变量非等距模型对中国汉族成人左心室多普勒超声心动图测值生理性变异的校正方法

姚桂华, 陈湘云, 杨文静, 张青, 刘静, 梁欢, 孙慧, 许耀, 王丽, 徐金锋, 张澄, 孙丰荣, 张梅, 曾雪迎, 张运