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41.
Philip John McKerrow 《Robotics and Autonomous Systems》1993,11(3-4):205-211
A ring of ultrasonic sensors mounted on a mobile robot is used to map a room. The sensors are modelled with an arc model: the object causing the reflection lies on an arc with radius equal to the range and arc angle equal to twice the beam angle. By fusing sensing with motion, a surface is displayed as a sequence of arcs. In this paper, the algorithm for obtaining outline segments from the arcs is presented. 相似文献
42.
Target differentiation with simple infrared sensors using statistical pattern recognition techniques
Billur Barshan Author Vitae Tayfun Aytaç Author VitaeAuthor Vitae 《Pattern recognition》2007,40(10):2607-2620
This study compares the performances of various statistical pattern recognition techniques for the differentiation of commonly encountered features in indoor environments, possibly with different surface properties, using simple infrared (IR) sensors. The intensity measurements obtained from such sensors are highly dependent on the location, geometry, and surface properties of the reflecting feature in a way that cannot be represented by a simple analytical relationship, therefore complicating the differentiation process. We construct feature vectors based on the parameters of angular IR intensity scans from different targets to determine their geometry and/or surface type. Mixture of normals classifier with three components correctly differentiates three types of geometries with different surface properties, resulting in the best performance (100%) in geometry differentiation. Parametric differentiation correctly identifies six different surface types of the same planar geometry, resulting in the best surface differentiation rate (100%). However, this rate is not maintained with the inclusion of more surfaces. The results indicate that the geometrical properties of the targets are more distinctive than their surface properties, and surface recognition is the limiting factor in differentiation. The results demonstrate that simple IR sensors, when coupled with appropriate processing and recognition techniques, can be used to extract substantially more information than such devices are commonly employed for. 相似文献
43.
Carrot slices of 3.5 mm thickness were dried in a laboratory microwave vacuum dryer at five different microwave power density levels of 2, 4.66, 7.33, 10, and 12.66 W/g and at three vacuum chamber pressure levels of 6.66, 19.98, and 33.3 kPa to 4-6% d.b. moisture content. Inside the dryer the sample holding plate was rotated with the speed of 4 rpm for uniform microwaves application. The drying rates were increased with the increase in microwave power density at all pressure levels and the Page model was found to be the most suitable model to predict the drying behavior of carrot slices at all process conditions. The Page model drying rate constant (k, min-1) showed high correlation with microwave power density at constant pressure by a power law equation and showed a logarithmic relationship with the microwave power density and pressure. Similar to the drying rate constant, the average moisture diffusivity at constant pressure was found to be function of microwave power density by power law equation as well as was also dependent on the power density and pressure by a logarithmic relationship. 相似文献
44.
针对贵州茅台酒厂股份有限公司锅炉除渣机经常卡死,导致煤渣不能及时从锅炉燃烧室排出,从而影响正常作业的问题,设计出以微控制器为核心的锅炉除渣机转速报警器。 相似文献
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47.
为解决高海拔地区输电线路运行维护检修存在的传感器供电可靠性差、无移动信号区域数据传输难度大的问题,文中提出了一种基于异构物联网络的输电线路智慧巡检方法。首先,研究了风光协同的传感器供电技术,实现了高海拔地区恶劣环境下输电线路监测传感器的可靠供电;其次,建立了异构的输电线路物联网络,实现了输电线路无移动信号传感器的数据采集。在此基础上,通过深度学习对所采集数据样本进行分析,实现对输电线路的智慧巡检;最后,将所提方法在某无信号地区110 kV线路的现场运行,其结果验证了所提方法的有效性和可行性。 相似文献
48.
Yanlin Zhang Xubin Zhu Yitao Liu Li Liu Qiang Xu Hao Liu Wei Wang Li Chen 《大分子材料与工程》2021,306(8):2100113
Wearable human–computer interaction equipment is a common technology, which can improve the comfort, convenience, and safety of the human body, and also can monitor human health. The flexible and wearable tensile sensor can be conveniently installed on clothes or directly connected to the body. This provides a convenient, timely, and portable solution for the detection of human motion. Therefore, wearable electronic equipment is gaining more attention. In this paper, a highly stretchable, flexible, and sensitive strain sensor which is based on multi-walled carbon nanotubes/Ecoflex nanocomposites is reported. A monofilament tensile sensor obtains good linearity (10.77%), low hysteresis (1.63%), good stability (6000 cycles under 100% strain), and ultra-high strain range (ε = 1300%). This ultra-stretchable sensor has potential applications in human motion monitoring, medical rehabilitation, health monitoring, human–computer interaction, and soft robots. 相似文献
49.
Rafael S. Pinto João P. Serra João C. Barbosa Renato Gonçalves Maria M. Silva Senentxu Lanceros-Méndez Carlos M. Costa 《大分子材料与工程》2021,306(11):2100372
Considering the high levels of materials used in the fields of electronics and energy storage systems, it is increasingly necessary to take into consideration environmental impact. Thus, it is important to develop devices based on environmentally friendlier materials and/or processes, such as additive manufacturing techniques. In this work, poly(vinylidene fluoride) (PVDF) and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) are prepared by direct-ink-writing (DIW) by varying solvent evaporation temperature and fill density percentage. Different morphologies for both polymers are obtained, including dense films and porous membranes, as well as different electroactive β-phase content, thermal and mechanical properties. The dielectric constant and piezoelectric d33 coefficient for dense films reaches up to 16 at 1 kHz and 4 pC N−1, respectively for PVDF-HFP with a fill density of 80 and a solvent evaporation temperature of 50 °C. Porous structures are developed for battery separator membranes in lithium-ion batteries, with a highest ionic conductivity value of 3.8 mS cm−1 for the PVDF-HFP sample prepared with a fill density of 100 and a solvent evaporation temperature of 25 °C, the sample showing an excellent cycling performance. It is demonstrated that electroactive films and membranes can be prepared by direct-ink writing suitable for sensors/actuators and energy storage systems. 相似文献
50.
Wei Zhang Chang Ma Ling-Zhi Huang Wen-Yan Guo Dan-Dan Li Jing Bian Ming-Guo Ma 《大分子材料与工程》2021,306(12):2100549
Conductive hydrogels have received widespread attention in the applications of biosensors, human–machine interface, and health recording electrodes. Herein, the conductive hydrogels integrated with antifreezing, water retention, reusable, and sensing performances are fabricated by introducing polyvinyl alcohol, cellulose nanofibril, MXene nanosheets, and glycerol. The as-prepared hydrogels present prominent electrical conductivity (2.58 mS cm−1) and flexibility even at −18 °C. In addition, the hydrogels have favorable water retention performance and can reuse after heating and cooling. When used as sensors, the hydrogels illustrate high sensitivity (gauge factor of 2.30), fast response time (0.165 s), wide working strain range (559%), favorable linearity (R2 = 0.999), and wide operating temperature range (−18 to 60 °C). The hydrogels can detect not only large strains of 10–200%, but also small strains of 1–5%, making them promising candidates for wearable sensors to monitor large and subtle movements. 相似文献