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Compound eyes of insects and crustaceans： Some examples that show there is still a lot of work left to be done

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Insect Science 2015年第3期22卷 461-481页

作者： Victor Benno Meyer-Rochow Department of Biology University of Oulu P.O. Box 3000 FIN-90014 Oulu Finland

Similarities and differences between the 2 main kinds of compound eye （apposition and superposition） are briefly explained before several promising topics for research on compound eyes are being introduced. Research on the embryology and molecular control of the development of the insect clear-zone eye with superposition optics is one of the suggestions, because almost all of the developmental work on insect eyes in the past has focused on eyes with apposition optics. Age- and habitat-related ultrastructural studies of the retinal organization are another suggestion and the deer cad Lipoptena cervi, which has an aerial phase during which it is winged followed by a several months long parasitic phase during which it is wingless, is mentioned as a candidate species. Sexual dimorphism expressing itself in many species as a difference in eye structure and function provides another promising field for compound eye researchers and so is a focus on compound eye miniaturization in very small insects, especially those that are aquatic and belong to species, in which clear-zone eyes are diagnostic or are tiny insects that are not aquatic, but belong to taxa like the Diptera for instance, in which open rather than closed rhabdoms are the rule. Structures like interommatidial hairs and glands as well as corneal microridges are yet another field that could yield interesting results and in the past has received insufficient consideration. Finally, the dearth of information on distance vision and depth perception is mentioned and a plea is made to examine the photic environment inside the foam shelters of spittle bugs, chrysales of pupae and other structures shielding insects and crustaceans.

关键词： aging miniaturization photoreceptors sexual dimorphism vision

Novel Methodology for Designing Frequency Selective Surfaces with Miniaturized Cells

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 1-6页

作者： Guo-Hui Yang Wan-Lu Li Tong Zhang Qun Wu Xue-Mai Gu Dept. of Microwave Engineering Harbin Institute of Technology The Fu Foundation School of Engineering and Applied Science Columbia University

miniaturization of Frequency Selective Surface's ( FSS's) size is significant for its application in the limited space. In this paper, a novel methodology for designing low-profile FSS is discussed, and a corresponding multi-layer structure with lumped elements for band-pass response is presented. Based on the equivalent circuit theory,the inductive designed center layer is firstly discussed. Then different numbers of additional capacitive designed layers are added and their performances are presented. Finally,the lumped elements are added both between adjacent layers and between adjacent cells of the additional layers so that the miniaturization performance can be further improved. The simulations for each structure in waves of different polarizations and incident angles are conducted,and the results are presented,which demonstrate the claimed characteristics of the proposed structure.

关键词： FSS miniaturization multi-layer polarization stability

Efficacy of biofeedback therapy via a mini wireless device on sleep bruxism contrasted with occlusal splint:a pilot study

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The Journal of Biomedical Research 2015年第2期29卷 160-168页

作者： WeiPing Gu Jie Yang FeiMin Zhang XinMin Yin XiaoLong Wei Chen Wang Jiangsu Key Laboratory of Oral Diseases Nanjing Medical University Department of General Dentistry Affiliated Hospital of StomatologyNanjing Medical University Department of Stomatology Jiangsu province Geriatric InstitutionJiangsu Province Official Hospital Department of Prosthodontics Affiliated Hospital of StomatologyNanjing Medical University Department of Stomatology Benq Medical CenterNanjing Medical University College of Automation Engineering Nanjing University of Aeronautics and Astronautics

The putative causes of bruxism are multifactorial and there are no definite measures for bruxism *** aim of this study was to evaluate the efficacy of biofeedback therapy on sleep bruxism,compared with occlusal ***-four volunteers with sleep bruxism were divided into two groups：the GTB group that were treated with biofeedback therapy（n 512） and the GTO group that were treated with occlusal splint（n 512）.A mini pressure sensor integrated with a monitoring circuit by use of a maxillary biofeedback splint was *** foster the relaxation of the masticatory muscles and the nervous system,the wireless device received signals from bruxism events and vibrations alerted the bruxer when the threshold was *** episodes and average duration of bruxism events during8 hours of sleep were analyzed with the monitoring program（TRMY1.0）.After 6 and 12 weeks,the episodes（P 50.001） and duration（P,0.05） in the GTB group declined *** contrast,there were no significant differences in the GTO group after the treatment（P.0.05）.Furthermore,the episodes had significant differences between the GTB group and the GTO group after the same period of treatment（P 5 0.000）.The results suggest that biofeedback therapy may be an effective and convenient measure for mild bruxers,when compared with occlusal splint *** mini wireless biofeedback method may be of value for the diagnosis and management of bruxism in the future.

关键词： sleep bruxism biofeedback occlusal splint miniaturization vibration wireless technology

Adaptive piezoelectric Vibration Control using PWM based Switching Power Amplifier

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Adaptive piezoelectric Vibration Control using PWM based Swi...

MINIATURIZED MICROSTRIP BRANCH-LINE COUPLER WITH GOOD HARMONIC SUPPRESSION PERFORMANCE

第36届中国控制会议

作者： Bo Wang Wei Tang Xiaoke Zheng Yuwei Wang Libo Wang School of Automation Northwestern Polytechnical University College of Engineering The Australian National University

ISBN: (纸本)9781538629185

In recent years,the miniaturization and low power consumption of vibration control systems have received continuous attention in the field of flutter suppression,In previous studies,active vibration control systems relied heavily on traditional power *** the traditional power amplifier has the disadvantage of high power consumption and poor flexibility,an active vibration control system using PWM based switching power amplifier is presented in this *** proposed method has the advantage of low power consumption,high efficiency and high ***,the weight and volume of the power amplifier is greatly *** experimental results show that the proposed system can effectively reduce the structural vibration.

关键词： miniaturization low power consumption switching power amplifier PWM

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Journal of Electronics(China) 2012年第1期29卷 132-136页

作者： Yang Guo Li Bo Kang Wei Ge Sheng Ministerial Key Laboratory of JGMT Nanjing University of Science and TechnologyNanjing 210094China

This paper presents a miniaturized microstrip branch-line coupler with good harmonic suppression performance. The proposed coupler consists of four branch-line sections, each of which is loaded by open-circuit stubs both at the center and the two ends. This type of loading can realize size reduction and harmonic suppression. As an example, a proposed branch-line coupler operating at 1.0 GHz is designed, fabricated and measured. The results show that the proposed branch-line coupler occupies 67% size of a conventional one and has better than 20 dB suppression from 1.9 to 5.8 GHz. Furthermore, the high slop of the transition band ensures good selectivity of the coupler.

关键词： Branch-line coupler miniaturization Harmonic suppression

Miniaturized Rotman lens with applications to wireless communication

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Frontiers of Information Technology & Electronic Engineering 2020年第1期21卷 144-158页

作者： Bao-hua SUN Qiu-yan LIANG Gao-nan ZHOU National Key Laboratory of Science and Technology on Antenna and Microwave Xidian UniversityXi’an 710071China

Rotman lens is a type of beamforming network with many advantages,such as true-time delay characteristic,multibeam capability,and wide *** lens has been used in a wide range of applications in today’s wireless communication ***,the size of a conventional Rotman lens is considerably ***,difficulties may arise with respect to its integration with base station antennas in wireless communication *** this study,three techniques for the miniaturization of a Rotman lens,i.e.,Chebyshev impedance transformers,power dividers,and truncated ports with energy distribution slots,are introduced to design the Rotman lens to reduce the size of the ports and hence the total area occupied by the Rotman *** and measurement results indicate that good impedance matching between the lens body and its feed lines can be *** the proposed truncated ports with energy distribution slots,the size of the Rotman lens can be greatly reduced without performance degradation or production cost ***,two possible applications of the proposed miniaturized Rotman lens to wireless communication systems are *** lens can not only provide multiple phase difference signals along the array ports to realize multibeams,but also generate high-performance formed beams such as flat-topped radiation pattern.

关键词： Rotman lens miniaturization Multibeam Beamformer Wireless communication

A compact and closed-loop spin-exchange relaxation-free atomic magnetometer for wearable magnetoencephalography

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Chinese Physics B 2023年第4期32卷 277-282页

作者：郭清乾胡涛冯晓宇张明康陈春巧张欣姚泽坤徐佳玉王青付方跃张寅常严杨晓冬 Suzhou Institute of Biomedical Engineering and Technology Chinese Academy of SciencesSuzhou 215163China School of Biomedical Engineering(Suzhou) Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230026China Jihua Laboratory Foshan 528000China School of Electronic and Information Engineering Changchun University of Science and TechnologyChangchun 130022China

Atomic magnetometers operated in the spin-exchange relaxation-free(SERF)regime are the promising sensor to replace superconducting quantum interference devices(SQUIDs)in the biomagnetism *** SERF magnetometer with compact size and good performance is crucial to the new generation of wearable magnetoencephalography(MEG)*** this paper,we developed a compact and closed-loop SERF magnetometer with the dimensions of 15.0×22.0×30.0 mm^(3)based on a single-beam *** bandwidth of the magnetometer was extended to 675 Hz while the sensitivity was maintained at 22 f T/Hz^(1/2).A nearly 3-fold enhancement of the bandwidth was obtained in comparison with the open-loop *** implementation of the closed-loop control also greatly improved the dynamic range,enabling the magnetometer to be robust against the disturbance of the ambient ***,the magnetometer was successfully applied for the detection of humanα-rhythm and auditory evoked fields(AEFs),which demonstrated the potential to be extended to multi-channel MEG measurements for future neuroscience studies.

关键词： atomic magnetometer miniaturization closed-loop magnetoencephalography(MEG)

Miniaturized Cell Lysis Device Using Spherically Focused Ultrasound

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Tsinghua Science and Technology 2003年第4期8卷 487-492,497页

作者：李刚肖宏郭旻程京 Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China National Engineering Research Center for Beijing Biochip Technology Beijing 100084 China

A prototype of a miniaturized cell lysis device developed using a concave spherical transducer is capable of lysing bacteria without added chemical denaturants, enzymes or microparticles and is capable of efficiently lysing yeast without any mechanical or enzymatic pretreatment. The device is designed for miniature bio analysis systems where cell lysing is needed to obtain intracellular materials for further analysis such as DNA identification. The device lysis efficiency was evaluated using viable cell counts and microscopy. Additionally, the device efficiency was compared with that of traditional chemical cell lysis methods using standard molecular biological techniques such as agarose gels and ultraviolet (UV) spectroscopy. The results indicate that efficient bacteria and cell disruption can be achieved through a low voltage driven and spherically focused high frequency ultrasonic device.

关键词： cell lysis spherically focused ultrasound miniaturization sample pre preparation

An overview of studies on marine macrobenthic community structure and biodiversity in the Bohai Sea

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Marine Science Bulletin 2020年第1期22卷 32-42页

作者： ZHU Haoran YU Yang LIU Xianbin Tianjin Marine Environmental Protection and Restoration Technology Engineering Researching Center Tianjin University of Science&TechnologyTianjin 300457China

Due to the further intense human urbanization and industrialization,the environmental problems and climate changes became global issues that we have to face *** increasing environmental pollutants,ocean eutrophication,red-tide and acidification are causing irrevocably damages to the marine ecological *** an important part of marine ecosystem,macrobenthos plays an essential role in energy flow and substance circulation in the marine ***,the study of macrobenthic community structures and diversities were necessary,meanwhile the protection of macrobenthic diversity was also a tough *** recent years,many researches were mainly focus on Jiaozhou Bay of the Yellow Sea,the Yangtze Estuary,the coastal of Zhejiang and Fujian Provinces,while seldom on benthic organisms in the Bohai *** this paper,the community structures and diversities of the common macrobenthos in the Bohai Sea were introduced and the macrobenthic response to environmental changes and environmental pollution caused by the construction of the Bohai Sea were also *** results showed that the large benthic fauna in th Bohai Sea was relatively simple compared to other China *** were about 400 species of large benthic *** dominant species were low temperature and wide salt warm *** the last five years,the annual average biomass was 23.82 g/m^2 and the annual average density was 1498 ind/m^*** seasonal variation of average habitat density was usually summer autumn spring winter,and the average biomass was usually autumn spring summer *** communities were destroyed and the dominant species appeared to be miniaturized caused by abuse of marine *** the 21st century,the number of crustacean arthropods,bivalve molluscs,and echinoderms have decreased rapidly,but the number of polychaetes and small molluscs increased *** the development of the comprehensive ecological management of the Bohai Sea,the ecological

关键词： Bohai Sea macrobenthos communication biodiversity miniaturization