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Design and Experiment on a Biomimetic Robotic Fish Inspired by Freshwater Stingray

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Journal of Bionic Engineering 2015年第2期12卷 204-216页

作者： Yangwei wang Jinbo tan Dongbiao Zhao College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Freshwater stingrays undulate their flexible disc-like pectoral fins to perform cruising, manoeuvring, and other motions. This undulatory propulsion has a higher propulsive efficiency and more precise manoeuvrability than most other species at low swimming velocity. In the current study, a new robotic fish inspired by the freshwater stingray was developed and tested. First, the morphology and kinematic patterns of the freshwater stingray were presented. A kinematic model of the pectoral fin was established based on several assumptions. Then a robotic stingray with an undulatory pectoral fin was designed and developed. Experiments were conducted to investigate the effects of various fin actuation parameters on its linear swimming velocity and the forces generated by the robotic stingray. The controllable fin parameters include oscillation frequency, wave number, maximal angular deflection of the fin rays, and the amplitude pattern of the pectoral fin. The experimental results indicate that the developed prototype is able to generate adequate thrust for self-propulsion. Linear swimming velocity and surge force increase rapidly with oscillation frequency, angular deflection, and wave number. A maximum velocity of 4.3 cm.s 1 （nearly 0.18 Body Lengths per second （BL·s-1）） and a maximum surge force of 102 mN are achieved at an oscillation frequency of 0.5 Hz, a wave number of 1, a maximum angular deflection of 30°, and an equal amplitude pattern. The sway force of the robotic fish fluctuates around 0 mN. The heave force varies with wave number and reaches its minimum at a wave number of 1.

关键词： robotic fish freshwater stingray undulatory pectoral fin experimental research

Comparison study on the annealing behaviors of dispersion strengthened copper alloys with different nanoparticles

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Rare Metals 2007年第5期26卷 456-462页

作者： GUO Mingxing wang Mingpu LEI Ruoshan tan wang JIN Peng School of Materials Science and Engineering Central South University Changsha 410083 China

The hardness measurement,optical microscopy （OM）,and transmission electron microscopy （TEM） microstructure observation on the annealing behaviors of Cu-Al2O3 （2.25 vol.% and 0.54 vol.% Al2O3） and Cu-0.52vol.%Nb alloys were carried out. The results show that with the increase of annealing temperature,the hardness of Cu-Al2O3 alloys decreases slowly. No change of the fiber structure formed by cold rolling in the Cu-2.25vol.%Al2O3 alloy is observed even after annealing at 900℃and the higher dislocation density can still be observed by TEM. Less combination of fiber formed by cold rolling and subgrains are observed in the Cu-0.54vol.%Al2O3 alloy annealed at 900℃. With the increase of annealing temperature,the hardness of the Cu-0.52vol.%Nb alloy exhibits a general decreasing trend,and its falling rate is higher than that of the Cu-Al2O3 alloys,indicating that its ability of resistance to softening at elevated temperature is weaker than that of the Cu-Al2O3 alloys. However,when annealed at a temperature of 300-400℃,probably owing to the precipitation strengthening of niobium,the hardness of the Cu-0.52vol.%Nb alloy arises slightly. The fibers formed by cold rolling be-come un-clear and un-straight and have less combination,and considerably more subgrains are observed by TEM.

关键词： high-temperature properties hardness measurement Cu-Al2O3 alloy Cu-Nb alloy dispersion strengthening cold working annealing

Iterative optimization of detection threshold and throughput for secondary users in multiband cognitive radio systems

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The Journal of China Universities of Posts and Telecommunications 2011年第6期18卷 27-37页

作者： SHI Cong wang Ying wang tan ZHANG Ping Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In cognitive radio （CR） systems, efficient spectrum sensing ensures the secondary user （SU） to successfully access the spectrum hole. Typically, the detection problem has been considered separately from the optimization of transmission strategy. However, in practice, due to non-zero probabilities of miss detection and false alarm, the sensing phase has an impact on the throughput of SUs as well as on the transmission of primary user （PU）. In this paper, using energy detection, we maximize the total throughput of SUs by jointly optimizing the detection threshold and transmission strategy in multiband CR systems. A set of iteration based algorithms are proposed to solve this mix-integer programming problem, which show better performance compared with uniform detection threshold selection algorithm suggested by IEEE 802.22 standard.

关键词： iteration optimization energy detection resource allocation multiband cognitive radio system

The Analysis on the Candidate Frequency Bands of Future Mobile Communication Systems

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China Communications 2015年第S1期12卷 140-149页

作者： tan Haifeng LI Wei wang tan FANG Jian FENG Zhiyong Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications The State Radio Monitoring Center(The State Radio Spectrum Management Center)

Appropriate candidate frequency bands are extremely important for the development of future 5G systems. In this work, the researches on 5G spectrum around the world are summarized. Then the potential candidate frequency bands for 5G systems are investigated based on practical utilization of spectrum in China. For spectrum below 6GHz, the feasibility of possible frequency bands for 5G system are analyzed, which mainly come from 2G/3G/4G spectrum re-farming, the spectrum identified by footnotes for IMT systems in Regulations on the Radio Frequency Allocation of China, and potential candidate bands from WRC-15 Agenda Item 1.1. Moreover, propagation characteristics of WRC-15 candidate frequency bands proposed by China are measured and modeled to verify their effectiveness. For spectrum above 6GHz, the potential candidate frequency bands for 5G systems are selected based on the preliminary analysis of spectrum allocation, allotment and the current usage in China. Suggestions are provided for further studies on 5G spectrum.

关键词： IMT system 5G spectrum mobile service candidate frequency band 6GHz

Multi-sources information fusion algorithm in airborne detection systems

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Journal of Systems Engineering and Electronics 2007年第1期18卷 171-176页

作者： Yang Yan Jing Zhanrong Gao tan wang Huilong Coll. of Electronic Information Engineering Northwestern Polytechnical Univ. Xi'an 710072 P. R. China

To aim at the multimode character of the data from the airplane detecting system, the paper combines Dempster- Shafer evidence theory and subjective Bayesian algorithm and makes to propose a mixed structure multimode data fusion algorithm. The algorithm adopts a prorated algorithm relate to the incertitude evaluation to convert the probability evaluation into the precognition probability in an identity frame, and ensures the adaptability of different data from different source to the mixed system. To guarantee real time fusion, a combination of time domain fusion and space domain fusion is established, this not only assure the fusion of data chain in different time of the same sensor, but also the data fusion from different sensors distributed in different platforms and the data fusion among different modes. The feasibility and practicability are approved through computer simulation.

关键词： Information fusion Dempster-Shafer evidence theory Subjective Bayesian algorithm Airplane detecting system

Comparison of downlink transmission strategies for distributed antenna systems with multi-antenna arrays

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The Journal of China Universities of Posts and Telecommunications 2010年第1期17卷 44-50页

作者： wang tan wang Ying SUN Kai CHEN Zi-xiong Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In multi-user distributed antenna systems （DAS）, the scenario where each distributed antenna port is a multi-antenna array has not been comprehensively studied. In this article, four simple extended methods for downlink transmission are analyzed and compared in this scenario, two of which are based on the block diagonalization （BD） algorithm, namely joint BD and intra BD method. The other two methods are joint time division multiplexing （TDM） method and central antenna system （CAS） method. These four methods are evaluated through both theoretic analysis and insightful simulations. The theoretic analysis includes the receiving signal combination, post-processing signal to interference plus noise ratio （SINR） calculation. It shows that the intra BD method requires less channel state information at the transmitter （CSIT） and has lower computational complexity and process latency. Simulation results show that the joint BD method provides the best performance, and the intra BD method suffers little performance loss. Overall, the intra BD method is proved to be an optimal tradeoff which achieves high capacity, especially for the cell edge users, with relatively low complexity when power constraints are considered.

关键词： BD DAS downlink transmission power constraints multi-user

High plastic Zr–Cu–Fe–Al–Nb bulk metallic glasses for biomedical applications

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International Journal of Minerals,Metallurgy and Materials 2015年第6期22卷 648-653页

作者： Shu-shen wang Yun-liang wang Yi-dong Wu tan wang Xi-dong Hui State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

Four Zr–Cu–Fe–Al-based bulk metallic glasses（BMGs） with Zr contents greater than 65at% and minor additions of Nb were designed and prepared. The glass forming abilities, thermal stabilities, mechanical properties, and corrosion resistance properties of the prepared BMGs were investigated. These BMGs exhibit moderate glass forming abilities along with superior fracture and yield strengths compared to previously reported Zr–Cu–Fe–Al BMGs. Specifically, the addition of Nb into this quaternary system remarkably increases the plastic strain to 27.5%, which is related to the high Poisson＇s ratio and low Young＇s and shear moduli. The Nb-bearing BMGs also exhibit a lower corrosion current density by about one order of magnitude and a wider passive region than 316 L steel in phosphate buffer solution（PBS, pH 7.4）. The combination of the optimized composition with high deformation ability, low Young＇s modulus, and excellent corrosion resistance properties indicates that this kind of BMG is promising for biomedical applications.

关键词： metallic glasses biomedical materials mechanical properties corrosion resistance zirconium content niobium addition

A PUF-Based and Cloud-Assisted Lightweight Authentication for Multi-Hop Body Area Network

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Tsinghua Science and Technology 2021年第1期26卷 36-47页

作者： wang Xiao tan Jiliang Zhang Yuanjing Zhang Zheng Qin Yong Ding Xingwei wang the College of Computer Science and Electronic Engineering Hunan UniversityChangsha 410082China Cyberspace Security Research Center Peng Cheng LaboratoryShenzhen 518000China Guangxi Key Laboratory of Cryptography and Information Security Guilin University of Electronic TechnologyGuilin 541004China the College of Computer Science and Engineering Northeastern UniversityShenyang 110004China

Wireless sensor technology plays an important role in the military,medical,and commercial fields *** Body Area Network(WBAN)is a special application of the wireless sensor network in human health monitoring,through which patients can know their physical condition in real time and respond to emergencies on *** reliability,guaranteed by the trust of nodes in WBAN,is a prerequisite for the effective treatment of ***,authenticating the sensor nodes and the sink nodes in WBAN is *** paper proposes a lightweight Physical Unclonable Function(PUF)-based and cloud-assisted authentication mechanism for multi-hop body area networks,which compared with the star single-hop network,can enhance the adaptability to human motion and the integrity of data *** authentication mechanism can significantly reduce the storage overhead and resource loss in the data transmission process.

关键词： Physical Unclonable Function(PUF) hardware security Wireless Body Area Network(WBAN)

Portable device for on-site detection of ammonia nitrogen

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Information Processing in Agriculture 2022年第4期9卷 475-484页

作者： Xianbao Xu Zhuangzhuang Bai tan wang National Innovation Center for Digital Fishery China Agricultural UniversityBeijing 100083China Key Laboratory of Smart Farming Technologies for Aquatic Animals and Livestock Ministry of Agriculture and Rural AffairsBeijing 100083China Beijing Engineering and Technology Research Center for Internet of Things in Agriculture China Agricultural UniversityBeijing 100083China College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTaian 271018China

Portable measurement of ammonia nitrogen in water is of great significance for water qual-ity ***’s beneficial to reduce biological diseases and promote aquatic product *** methods such as Nessler’s reagent method suffer from complex opera-tion,time delays and toxic *** realize simple and pollution-free detection,this paper develops a low-cost portable device for ammonia nitrogen detection.A test paper was proposed to cooperate the device and offer a chromogenic *** portable device reduces the impact of any ambient light,simplifies the operation,and provides human–computer *** result obtained for the detection range of 0.4–10 mg/L(R^(2) are 0.9902 and 0.9893 for the rang of 0.4–4.5 and 4.5–10 mg/L,respectively)with the detection limit of 0.36 mg/L,and the average recovery of aquaculture water is 100.98–137.75%.The results show that the portable device can provide a great potential for on-site detection ammonia nitrogen concentration.

关键词： Ammonia nitrogen measurement Colorimetric detection Portable device Test paper Aquaculture