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60 GHz；封装天线；共面波导馈电环形谐振器；玻璃集成无源器件；超表面天线；小型化天线 1

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罗特曼透镜；微型化；多波束；波束形成器；无线通信 1

视觉知识表达；视觉识别；视觉形象思维模拟；视觉知识学习；多重知识表达 1

超宽带；天线；超材料 1

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A new miniaturized engine based on thermomagnetic effect of magnetic fluids

Lujun ZHOU, Yimin XUAN, Qiang LI, Wenlei LIAN

《能源前沿（英文）》 2009年第3卷第2期页码 160-166 doi: 10.1007/s11708-009-0018-9

摘要： A new engine system, essentially consisting of a permanent NdFeB magnet, a kerosene-based magnetic fluid and a rotor, is proposed based on the thermomagnetic effect of a temperature-sensitive magnetic fluid. The rotor was driven by the thermal convection of the magnetic fluid in the presence of a homogeneous external magnetic field. A digital camera was used to record the rotation speed of the rotor to investigate the performance of the engine system under varying conditions such as heat load, heat sink temperature, and magnetic field distribution. The peak angle velocity obtained for the rotor was about 2.1 rad/min. The results illustrate that the rotation speed of the rotor increases as the input heat load increases, or as the heat sink temperature decreases. The performance of the motor is considerably influenced by the magnetic field imposed. Therefore, the performance of such an engine can be controlled conveniently by changing the external magnetic field and/or the temperature distribution in the fluid.

关键词： magnetic fluid thermomagnetic effect engine

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基于纳米金/介孔NiO/泡沫镍纳米复合材料的微型电极用于地下水重金属检测 Article

薛博元, 杨倩, 夏楷东, 李志宏, 陈宇徽, 张大奕, 周小红

《工程（英文）》 2023年第27卷第8期页码 199-208 doi: 10.1016/j.eng.2022.06.005

摘要：

Heavy metals, notably Pb²⁺ and Cu²⁺, are some of the most persistent contaminants found in groundwater. Frequent monitoring of these metals, which relies on efficient, sensitive, cost-effective, and reliable methods, is a necessity. We present a nanocomposite-based miniaturized electrode for the concurrent measurement of Pb²⁺ and Cu²⁺ by exploiting the electroanalytical technique of square wave voltammetry. We also propose a facile in situ hydrothermal calcination method to directly grow binder-free mesoporous NiO on a three-dimensional nickel foam, which is then electrochemically seeded with gold nanoparticles (AuNPs). The meticulous design of a low-barrier Ohmic contact between mesoporous NiO and AuNPs facilitates target-mediated nanochannel-confined electron transfer within mesoporous NiO. As a result, the heavy metals Pb²⁺ (0.020 mg·L⁻¹ detection limit, 2.0–16.0 mg·L⁻¹detection range) and Cu²⁺ (0.013 mg·L⁻¹ detection limit, 0.4–12.8 mg·L⁻¹ detection range) can be detected simultaneously with high precision. Furthermore, other heavy metal ions and common interfering ions found in groundwater showed negligible impacts on the electrode's performance, and the recovery rate of groundwater samples varied between 96.3% ± 2.1% and 109.4% ± 0.6%. The compactness, flexible shape, low power consumption, and ability to remotely operate our electrode pave the way for onsite detection of heavy metals in groundwater, thereby demonstrating the potential to revolutionize the field of environmental monitoring.

关键词： AuNPs Mesoporous NiO Miniaturized electrode Heavy metal ions Groundwater Square wave voltammetry

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Human power-based energy harvesting strategies for mobile electronic devices

Dewei JIA, Jing LIU

《能源前沿（英文）》 2009年第3卷第1期页码 27-46 doi: 10.1007/s11708-009-0002-4

摘要： Energy problems arise with the proliferation of mobile electronic devices, which range from entertainment tools to life saving medical instruments. The large amount of energy consumption and increasing mobility of electronic devices make it urgent that new power sources should be developed. It has been gradually recognized that the human body is highly flexible in generating applicable power from sources of heat dissipation, joint rotation, enforcement of body weight, vertical displacement of mass centers, and even elastic deformation of tissues and other attachments. These basic combinations of daily activities or metabolic phenomena open up possibilities for harvesting energy which is strong enough to power mobile or even implantable medical devices which could be used for a long time or be recharged permanently. A comprehensive review is presented in this paper on the latest developed or incubating electricity generation methods based on human power which would serve as promising candidates for future mobile power. Thermal and mechanical energy, investigated more thoroughly so far, will particularly be emphasized. Thermal energy relies on body heat and employs the property of thermoelectric materials, while mechanical energy is generally extracted in the form of enforcement or displacement excitation. For illustration purposes, the piezoelectric effect, dielectric elastomer and the electromagnetic induction couple, which can convert force directly into electricity, were also evaluated. Meanwhile, examples are given to explain how to adopt inertia generators for converting displacement energy via piezoelectric, electrostatic, electromagnetic or magnetostrictive vibrators. Finally, future prospects in harvesting energy from human power are made in conclusion.

关键词： mobile electronic device human power energy harvesting micro/miniaturized generator battery green energy

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视觉知识的五个基本问题 Perspectives

潘云鹤

《信息与电子工程前沿（英文）》 2021年第22卷第5期页码 615-766 doi: 10.1631/FITEE.2040000

摘要：认知心理学早已指出，人类知识记忆中的重要部分是视觉知识，被用来进行形象思维。因此，基于视觉的人工智能（AI）是AI绕不开的课题，且具有重要意义。本文继《论视觉知识》一文，讨论与之相关的5个基本问题：（1）视觉知识表达；（2）视觉识别；（3）视觉形象思维模拟；（4）视觉知识的学习；（5）多重知识表达。视觉知识的独特优点是具有形象的综合生成能力，时空演化能力和形象显示能力。这些正是字符知识和深度神经网络所缺乏的。AI与计算机辅助设计/图形学/视觉的技术联合将在创造、预测和人机融合等方面对AI新发展提供重要的基础动力。视觉知识和多重知识表达的研究是发展新的视觉智能的关键，也是促进AI 2.0取得重要突破的关键理论与技术。这是一块荒芜、寒湿而肥沃的“北大荒”，也是一块充满希望值得多学科合作勇探的“无人区”。

关键词：视觉知识表达；视觉识别；视觉形象思维模拟；视觉知识学习；多重知识表达

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基于玻璃集成无源器件工艺的60-GHz小型化宽带超表面天线 Research Articles

Hai-yang XIA, Jin-can HU, Tao ZHANG, Lian-ming LI, Fu-chun ZHENG

《信息与电子工程前沿（英文）》 2020年第21卷第1期页码 174-181 doi: 10.1631/FITEE.1900453

摘要：提出一种面向封装天线应用的60-GHz小型化宽带超表面天线。基于玻璃集成无源器件制造技术，采用共面波导馈电环形谐振器表征玻璃基板的材料特性。该天线于高介电常数玻璃基板上设计以实现天线小型化。在TM10模式下，贴片单元之间的间隙使该天线贴片辐射孔径得以减小。该天线在结构上采用共面波导馈电，进而激励蝶形缝隙，最终耦合激励位于天线上表面的超表面贴片。该天线可同时支持TM10模和反相TM20模，从而提升带宽性能。经过设计、优化及加工，该天线的辐射贴片尺寸为0.31λ0×0.31λ0，厚度为0.06λ0。采用基于探针结构的天线测量装置完成该天线测试，测试结果显示天线带宽为53.3～67 GHz。在60 GHz频点处，该天线增益测量值约为5 dBi。

关键词： 60 GHz；封装天线；共面波导馈电环形谐振器；玻璃集成无源器件；超表面天线；小型化天线

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Development of meso-scale milling machine tool and its performance analysis

LI Hongtao, LAI Xinmin, LI Chengfeng, LIN Zhongqin, MIAO Jiancheng, NI Jun

《机械工程前沿（英文）》 2008年第3卷第1期页码 59-65 doi: 10.1007/s11465-008-0005-6

摘要： To overcome the shortcomings of current technologies for meso-scale manufacturing such as MEMS and ultra precision machining, this paper focuses on the investigations on the meso milling process with a miniaturized machine tool. First, the related technologies for the process mechanism studies are investigated based on the analysis of the characteristics of the meso milling process. An overview of the key issues is presented and research approaches are also proposed. Then, a meso-scale milling machine tool system is developed. The subsystems and their specifications are described in detail. Finally, some tests are conducted to evaluate the performance of the system. These tests consist of precision measurement of the positioning subsystem, the test for machining precision evaluation, and the experiments for machining mechanical parts with complex features. Through test analysis, the meso milling process with a miniaturized machine tool is proved to be feasible and applicable for meso manufacturing.

关键词： applicable machining mechanical overview positioning subsystem miniaturized

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微型罗特曼透镜在无线通信中的应用 Research Articles

Bao-hua SUN, Qiu-yan LIANG, Gao-nan ZHOU

《信息与电子工程前沿（英文）》 2020年第21卷第1期页码 144-158 doi: 10.1631/FITEE.1900501

摘要：罗特曼透镜是一种具有实时延迟特性、多波束性能和宽带等优点的波束成形网络，在当今无线通信系统中得到广泛应用。然而，在无线通信系统中，传统罗特曼透镜尺寸相当大，可能会影响其与基站天线的集成。介绍3种微型化罗特曼透镜技术（切比雪夫阻抗变换器、功率分配器和带能量分配槽的截断端口）设计透镜，减小端口尺寸，从而减小罗特曼透镜所占总面积。仿真和测量结果表明，该方法可实现透镜主体与馈线之间良好的阻抗匹配。利用该带能量分配槽的截断端口，可大大减小罗特曼透镜尺寸，同时不降低透镜性能或增加生产成本。此外，研究了该微型罗特曼透镜在无线通信系统中两种可能的应用。罗特曼透镜不仅可沿阵列端口提供多个相位差信号实现多波束，还可生成平顶辐射等高性能成形波束。

关键词：罗特曼透镜；微型化；多波束；波束形成器；无线通信

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The Twenty Third International Conference on Miniaturized Systems for Chemistry and Life Sciences (μTAS

会议日期： 2019年10月27日

会议地点：瑞士/巴塞尔城市

主办单位： Institute of Electrical and Electronics Engineers

一种改进的用于加载微型航天器小型化超宽带多共振贴片天线的新型H形裂环谐振器超材料 Article

Parul DAWAR, N. S. RAGHAVA, Asok DE

《信息与电子工程前沿（英文）》 2017年第18卷第11期页码 1883-1891 doi: 10.1631/FITEE.1601193

摘要：本文设计并分析了一种改进H形裂环谐振器（split ring resonator, SRR）的新型超材料。它具有负磁导率和负介电常数特性，且在X，Ku和Ka频带内具有多频共振特性。本文就超材料方向和位置的变化对不同配置下的贴片天线进行了分析。结果表明，新型超材料天线实现了性能优化，表现为9 dB的可观增益，77 GHz的带宽，100%的辐射效率，以及有源区65%的面积缩减。二阶分形超材料天线尺寸降至1/21，从而实现了高度小型化。该研究为急需小尺寸尖波束的通信领域提供了一种解决方案。

关键词：超宽带；天线；超材料

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